Rhode Island Code of Regulations
Title 650 - Coastal Resources Management Council
Chapter 20 - Coastal Management Program
Subchapter 05 - Ocean Special Area Management Plan
Part 8 - RICRMP: Ocean SAMP - Chapter 8 - Renewable Energy and Other Offshore Development (650-RICR-20-05-8)
Section 650-RICR-20-05-8.4 - Potential Effects on Existing Uses and Resources in the Ocean SAMP Area (formerly Section 850)
Universal Citation: 650 RI Code of Rules 20 05 8.4
Current through September 18, 2024
A. Offshore renewable energy may potentially affect the natural resources and existing human uses of the Ocean SAMP area. Some effects may be negative, resulting in adverse impacts on these resources and uses. Alternatively, other effects may be neutral, producing no discernible impacts, while others may be positive, resulting in enhancements to the environment or to offshore human uses. The degree to which offshore renewable energy structures may affect the natural environment or human activities in the area varies in large part on the specific siting of a project. Careful consideration when planning the location of an offshore renewable energy facility, as well as the use of appropriate mitigation strategies during the construction, operation and decommissioning stages can minimize any potential negative impacts (MMS 2007a).
B. To date, most research on the potential effects of offshore renewable energy installations has been conducted in Europe, though some research has been conducted during the review of the proposed offshore wind farm project in Nantucket Sound by Cape Wind, LLC (MMS 2009a; U.S. Coast Guard 2009; Technology Service Corporation 2008). In anticipation of future offshore renewable energy development within the U.S., BOEM has identified potential impacts and enhancements of such development on marine transportation, navigation and infrastructure in the "Programmatic Environmental Impact Statement for Alternative Energy Development and Production" (PEIS) (MMS 2007a). These sources, as well as other scientific literature and relevant reports have informed this synthesis of the potential effects on existing resources and uses in the Ocean SAMP area. Where possible, research conducted as a part of the Ocean SAMP process has been incorporated to help further assess the potential for effects within the Ocean SAMP study area.
C. As presented in § 810.3, offshore wind energy currently represents the greatest potential for utility-scale offshore renewable energy in the Ocean SAMP area. For that reason, the focus of this section is mainly on the potential effects from the development of offshore wind energy facilities. However, many of the potential effects discussed may be similar across all forms of offshore renewable energy development and offshore marine construction in general.
D. While this section is meant to provide a summary of all potential effects of offshore renewable energy development, the potential effects of a particular project will be thoroughly examined as part of the review conducted under the National Environmental Policy Act (NEPA). The review process includes: an analysis of alternatives, an assessment of all environmental, social, and existing use impacts (i.e. ecological, navigational, economic, community-related, etc.), a review for regulatory consistency with other applicable federal laws and the implementation of mitigation measures. See § 820.4 and Chapter 10, Existing Statutes, Regulations, and Policies for more information on the NEPA review process, as well as other state and federal reviews and regulations relevant to offshore wind energy development.
E. This section begins with an examination of the potential effects of offshore renewable energy development on the physical environment through a discussion of the potential for avoided air emissions and the potential effects on coastal processes. Next, the potential effects of offshore renewable energy development on the ecological resources, including the benthic ecology, avian species, sea turtles, marine mammals and fish. Potential effects to human uses are then examined through a discussion of cultural and historic resources, commercial and recreational fishing activities, recreation and tourism and lastly marine transportation, navigation and infrastructure. The final section considers the potential cumulative effects of offshore renewable energy development.
8.4.1 Avoided Air Emissions (formerly § 850.1)
A.
The development of an offshore wind farm or any other offshore renewable energy
project would have implications for air emissions within the state. While the
development of a project will produce some air emissions (especially during the
construction stage), a renewable energy project, by not burning fossil fuels,
will produce far fewer emissions of carbon dioxide and conventional air
pollutants. This section summarizes the effects of air emissions produced and
avoided by the development of an offshore renewable energy project.
B. Air emissions produced during conventional
fossil fuel energy production include carbon dioxide, sulfur dioxide, nitrogen
oxides, volatile organic compounds, particulate matter, and carbon monoxide.
These pollutants have been demonstrated to have detrimental impacts to human
health and the environment. Exposure to poor air quality is a major health risk
and health cost in the United States. Smog and particle pollution are the cause
of decreased lung function, respiratory illness, cardiovascular disease,
increased risk of asthma, and the risk of premature death (U.S. Department of
Energy 2008). The largest sources of sulfur dioxide emissions are from fossil
fuel combustion at power plants; sulfur dioxide has been linked to respiratory
illnesses and is a major contributor to acid rain (U.S. EPA Office of Air and
Radiation 2009). Nitrogen oxides combine with volatile organic compounds (VOCs)
to form ozone, a major component of smog. Ozone can cause a number of
respiratory problems in humans, and can also have detrimental effects on plants
and ecosystems, including acid rain. Additionally, nitrogen dioxide has also
been shown to cause adverse respiratory effects (U.S. EPA Office of Air and
Radiation 2009). The effects of carbon dioxide emissions, the major contributor
to global climate change, are discussed in further detail in Chapter 3, Global
Climate Change.
C. The process of
siting, constructing, and decommissioning an offshore renewable energy project
of any kind would entail some adverse impacts to air quality through the
emission of carbon dioxide and conventional pollutants. Construction activity
in the offshore environment would require the use of fossil fuel-powered
equipment that will result in a certain level of air emissions from activities
including pile installation, scour protection installation, cable laying,
support structure and turbine installation, and other activities required for
the development of a wind farm. During the pre-construction and installation
stages, there would be some air emissions in the Ocean SAMP area from fossil
fuel fired mobile sources such as ships, cranes, pile drivers and other
equipment. Decommissioning would also result in some air emissions from the
activities involved in the removal of the wind turbines, although emissions
from decommissioning would be lower than those involved in construction (MMS
2009a). The size of an offshore renewable energy facility's carbon footprint
will vary depending on the project, as the carbon footprint of a facility
depends on project specific factors (e.g. size, location, technology,
installation techniques, etc.) Any calculation of carbon footprint would
include the pre-construction, construction, operation, and decommissioning
phases of a project.
D. When
considering the benefits of wind power displacing electricity generated from
fossil fuels, the carbon dioxide (CO2) emissions of manufacturing wind turbines
and building wind plants need to be taken into account as well. White and
Kulsinski (1998) found that when these emissions are analyzed on a life-cycle
basis, wind energy's CO2 emissions are extremely low-about 1% of those from
coal and 2% of those from natural gas, per unit of electricity generated. The
American Wind Energy Association has calculated that a single 1 MW wind turbine
(operating at full capacity for one year) has the potential to displace up to
1,800 tons (1633 MT) of CO2 per year compared with the current U.S. average
utility fuel mix (made up of oil, gas, and coal) burned to produce the same
amount of energy (AWEA 2009). The generation of renewable wind energy will
result in avoided future emissions of CO2 and will allow Rhode Island to meet
targets set by the Regional Greenhouse Gas Initiative (RGGI) (See §
810.1).
E. Developing offshore
renewable energy sources in the form of wind turbines would have a positive
impact on air emissions by displacing future air emissions caused by generating
electricity. The level of avoided air emissions, and the net impact from
renewable energy, will be dependent upon the future demands for electricity in
Rhode Island, and the proportion of this which can be met by offshore wind
farms and other renewable energy sources. At the very least, an offshore wind
farm would have the effect of reducing the need for adding capacity for
fossil-fuel generating plants in Rhode Island and throughout New England. At
present, roughly 99% of the energy generated within Rhode Island comes from
combined cycle natural gas, which is considered a marginal generator, in that
it provides variable output which can easily be adjusted to meet demand (ISO
New England Inc. 2009c). NOx is the principal pollutant of concern for gas
fired energy generation (MMS 2009a). Much of the electricity used within Rhode
Island comes from the Brayton Point Power Station in Somerset, MA, the largest
fossil-fueled generating facility in New England. The Brayton Point Power
Station has three units that use coal and one that uses either natural gas or
oil, for a combined output of over 1500 MW (Dominion 2010). The additional
energy production from wind turbines would be more likely to result in avoided
air emissions from natural gas plants, which are marginal and would produce
less energy in the event demand was lowered because of the additional output of
wind turbines. Wind energy is also a marginal source, because wind speeds and
thus energy output varies. The Brayton Point Power Station, which because of
its reliance on coal is mostly a baseload generator, or one that does not
change short term output depending on demand (because of the difficulties in
doing so), would likely continue to produce energy at the same rate. Thus air
emissions from this plant would not be avoided, at least in the short
term.
F. A second important benefit
of switching to a zero-emission energy generation technology like wind power is
impact on air quality through reduced levels of nitrogen oxides, sulfur
dioxide, and mercury emitted in electrical energy generation using fossil
fuels. The Cape Wind FEIS determined that a wind farm would result in the net
reduction in emissions of NOx, a precursor of ozone, although only a slight
reduction because of the levels of NOx still being produced by power sources
elsewhere (MMS 2009a). The emissions of sulfur dioxide and nitrogen oxides have
declined significantly since the early 1990s (ISO New England Inc. 2009c).
However, there still may be a benefit in terms of avoided future increases in
emissions of NOx and other pollutants if a project can meet increasing future
energy demands. A reduction in these pollutants will have positive health
effects for residents of the state of Rhode Island from the perspective of
avoiding future respiratory illnesses.
8.4.2 Coastal Processes and Physical Oceanography (formerly § 850.2)
A. The following section summarizes the
general potential effects of a renewable energy project on coastal processes
and physical oceanography in the Ocean SAMP area. The introduction of a number
of large structures into the water column may have an effect on coastal
processes such as currents, waves, and sediment transport. The potential
effects to coastal processes as a result of offshore renewable energy
development are dependent on the size, scale and design of the facility, as
well as site specific conditions (i.e., localized currents, wave regimes and
sediment transport). As a result, the potential effects will vary between
projects and may even vary between different parts of a project site.
B. The potential effect of offshore renewable
energy structures in the water column on currents and tides have been examined
using modeling techniques. Modeling of the proposed Cape Wind project found
that the turbines would be spaced far enough apart to prevent any wake effect
between piles; any effects would be localized around each pile (MMS 2009a). The
analysis of Cape Wind demonstrated that the flow around the monopiles (which
range in diameter from 3.6-5.5 m [11.8-18.0 feet] wide) would return to 99% of
its original flow rate within a distance of 4 pile diameters (approximately
14.4-22 m [47.2-72.2 feet]) from the support structure (ASA 2005). Both of
these studies, however, are representative of monopile wind turbine subsurface
structure and may not be directly applicable to jacket-style foundations. The
potential localized effects of lattice jacket structures on the hydrodynamics
are likely to be even less compared to that found with monopiles as pile
diameters for lattice jackets are much smaller (1.5 m [4.9 feet]) than
monopiles (4-5 m [13-16.5 feet] diameter). Furthermore, the spacing between the
turbines using lattice jacket support structures will be much greater than the
4 pile diameters. However, the effects of currents may be site-specific, as
there could be localized currents or other conditions that could affect or be
affected by the presence of wind turbines; site specific modeling may be
necessary to determine impacts.
C.
One predicted potential effect of wind turbines has been changes to the wave
field from diffraction caused by the monopiles, and resulting changes to
longshore sediment transport (CEFAS 2005). A study of the wave effects at
Scroby Bank, located in the North Sea off the U.K., found no significant
effects to the wave regime (CEFAS 2005). Modeling of the effects of wind farms
on waves found a reduction in wave height on average of 1.5% in the region, and
maximum localized amplification of wave heights at the site of the wind farm of
about 0.0158 m (0.6 inches). As the modeled wind farm was moved further from
shore, the wave height amplification decreased (ABP Marine Environmental
Research Ltd 2002). Modeling for the Cape Wind project found that the largest
wave diffraction occurred for small waves with low bottom velocities that did
not cause significant sediment transport; larger waves were not affected by the
presence of the turbines. Overall, the models found that the presence of
turbines would have a negligible impact on wave conditions in the area (MMS
2009a). Because there are no significant changes predicted for tides and waves,
there are not expected to be significant effects to sediment movement or
deposition along the coastline (ABP Marine Environmental Research Ltd
2002).
D. Preliminary scaling
estimates for the cumulative generation of water column turbulence due to wakes
behind subsurface pilings, using parameters applicable to Ocean SAMP waters and
a 100-turbine wind power generation field, suggests their influence on vertical
mixing could be comparable to that due to bottom friction (Codiga and Ullman
2010c). The known persistence of stratification in much of the Ocean SAMP
region during summertime suggests that bottom friction is relatively weak, and
thus the effects of platform pilings are not expected to produce major, large
scale changes in water column stratification. However, additional research is
needed to address the extent to which the spatial patterns and seasonal cycle
of stratification in Ocean SAMP waters could potentially be altered by the
presence of arrays of various types (pilings, lattice jackets, etc.) of
subsurface structures as infrastructure for renewable energy generation
devices.
E. The turbine foundations
may increase turbulence and disrupt flow around the structures, potentially
causing local erosion around the structures, or "scour". This process is caused
by the orbital motion of water produced by waves and currents, and the vortices
that result as the water flows around the pile of a wind turbine or another
structure (MMS 2009a). Scour often results in the erosion of the sediments
supporting the structure as they are transported elsewhere, forming a hole at
the base. Scour can also affect sediments in areas between structures where
multiple structures are present, also known as "global scour". However, because
of the distances required between turbines, it has often been assumed that
global scour will be limited (MMS 2007b). In addition, the use of scour
protection such as boulders, grout bags or grass mattresses may be used to
minimize the effects if scouring on the seafloor (MMS 2007a).
F. The seabed disturbance during construction
and from scour may result in changes to sediment grain size. Smaller grains may
be transported if suspended during disturbance, leaving only grains too large
to be transported to remain. This could affect the structure of the benthic
habitat and its associated community (MMS 2007b).
G. The placement of submarine cables will
have limited and localized effects on seafloor sediments. Jet plowing, the
method most likely to be used in the Ocean SAMP area, will likely result in the
resuspension of bottom sediments into the water column. Heavier particles will
settle in the immediate area of the activity, but finer particles are likely to
travel from the disturbed area. These effects will be relatively small and
short-term, however. Modeling of sedimentation during the cable laying process
for the Cape Wind project found that sediment would settle within a few hundred
yards of the cable route (MMS 2009a). In some cases, where suspended sediment
levels are already high in the vicinity because of storms, areas of mobile
surface sediment, or fishing activities such as trawling, the additional
increase in sediments from cable-laying will probably not be significant. Once
it is buried, the cable will not likely have any significant effect on
sediments as long as it remains buried (ABP Marine Environmental Research Ltd
2002). If the cable becomes exposed, increased flow could occur above the
cable, resulting in localized sediment scour (MMS 2009a).
H. The cable laying process would form a
seabed scar from where the jet plow passed over. In some areas the scar may
recover naturally, over a period of days to months or years depending on local
tidal, current, and sediment conditions at various points along the cable route
(MMS 2009a). However, depending on extent and depth of scars and the site
specific conditions, areas which may not recover naturally may require the
bathymetry to be restored to minimize impacts.
I. Studies on the effects of radiated heat
from buried cables have found a rise in temperature directly above the cables
of 0.19ºC [0.342 ºF] and an increase in the temperature of seawater
of 0.000006ºC [0.0000108 ºF]. This is not believed to be significant
enough to be detectable against natural fluctuations (MMS 2009a).
J. Overall, it is unlikely that wind farms
will have a significant effect on wave, current, and sediment processes
overall, with only small effects within the areas of the wind farms. The
further to sea the wind farm is located, and the deeper water it is in, the
lesser the effects to coastal processes are likely to be (ABP Marine
Environmental Research Ltd 2002).
8.4.3 Benthic Ecology (formerly § 850.3)
A. Offshore renewable energy
development in the Ocean SAMP area, especially offshore wind energy
development, may potentially affect the benthic ecology of a project site by:
disturbing benthic habitat during construction activities; introducing hard
substrate that may be colonized and produce reef effects, or alter community
composition; generate noise or electromagnetic fields that may affect benthic
species; or impacting the water quality of an area during the installation or
operation of a facility. This section summarizes the general potential effects
of a renewable energy project on the Ocean SAMP area's benthic ecosystem;
potential effects of these phenomena on species groups (e.g., birds, marine
mammals, and finfish) are detailed below in separate sections.
B. Undoubtedly, the construction of large,
offshore structures will result in effects to coastal processes and to benthic
habitats and species, at least in the immediate vicinity of the turbine
installation. However, it may be a challenge to accurately assess changes in
the benthic ecology of the Ocean SAMP area unless a good baseline is
established. Studies of European offshore renewable energy projects, the PEIS
(MMS 2007a) and the Cape Wind FEIS (MMS 2009a) provide some insight into the
range of potential ecological effects offshore wind energy development, though
the specific effects produced within the Ocean SAMP area will vary depending on
site specific conditions and the size and design of the proposed
project.
C. Benthic habitat
disturbance (formerly § 850.3.1)
1. The
PEIS indicates that habitat disturbance may result through the construction of
offshore renewable energy infrastructure (MMS 2007a). Here, habitat disturbance
is used broadly to refer to sediment disturbance and settling; increased
turbidity of the waters in the construction area; and the alteration or loss of
habitat from installation of infrastructure including piles, anti-scour
devices, and other structures.
2.
Sediment disturbance caused by the installation of foundations or underwater
transmission cables may result in the smothering of some benthic organisms as
suspended sediments resettle onto the seafloor (MMS 2007a). Smothering would
primarily affect benthic invertebrates as most finfish and mobile shellfish
would move to nearby areas to avoid the construction site (MMS 2007a). The eggs
and larvae of fish and other species may be particularly susceptible to burying
(Gill 2005). Smaller organisms are more likely to be affected than larger ones,
as larger organisms can extend feeding and respiratory organs above the
sediment (BERR 2008). Sediment also has the potential to affect the filtering
mechanisms of certain species through clogging of gills or damaging feeding
structures; however, most species in the marine environment likely have some
degree of tolerance to sediment and this effect is likely to be minimal (BERR
2008). In the Ocean SAMP area, species that may be impacted by the settling of
sediments include eastern oysters (Crassostrea virginica) and northern quahogs
(Mercenaria mercenaria), among others, resulting in mortality or impacts to
reproduction and growth (MMS 2009a).
3. In addition to the disturbance of
sediments, construction of the foundation substructure and the installation of
cables may result in increased turbidity in the water column. This may in turn
affect primary production of phytoplankton and the food chain; however, these
effects are likely to be short-term and localized, as sediments will likely
settle out after a few hours or be flushed away by tidal processes (MMS 2009a).
Increased turbidity in a project area is generally temporary and will subside
once construction has been completed (Johnson et al. 2008).
Sediment suspension times will vary according to particle size and currents. In
Nantucket Sound, sediments were predicted to remain suspended for two to
eighteen hours, and the amount of sediment suspended would be minimal compared
with normal sediment transport within the region due to typical tidal and
current conditions (MMS 2009a). This may impact the abundance of planktonic
species by decreasing the availability of light in the water column. Sediment
suspended during the construction or decommissioning activities and transported
by local currents may result in impacts to neighboring habitats, perhaps posing
a temporary risk of smothering to nearby benthic species. Sediment transport in
the Ocean SAMP area will need to be further modeled to predict the potential
effects to turbidity from construction of offshore wind turbines.
4. Habitat conversion and loss may result
from the physical occupation of the substrate by foundation structures or scour
protection devices. Steel foundations and scour protection devices, which may
be made up of rock or concrete mattresses, may modify existing habitat, or
create of new habitat for colonization (Johnson et al. 2008).
The direct effects of these hard structures to the seabed are likely to be
limited to within one or two hundred meters of the turbine (OSPAR 2006).
Additionally, cables will need to be installed between turbines, and this will
require temporarily disturbing the sediment between the turbines. The total
area of seabed disturbed by wind turbine foundations is relatively small
compared to the total facility footprint. The scour protection suggested for
the Cape Wind project around each monopile vary depending on the pile and the
location, though the total scour protection area of 47.82 acres (0.19 square
kilometers). Compared to the total footprint of the Cape Wind project (64 km2
or 15,800 acres), the area affected by scour protection equals only 0.3% (MMS
2009a).
5. In addition to
physically changing benthic habitat, the placement of wind turbines, especially
in large arrays, may alter tidal current patterns around the structures (see
§ 8.4.2 of this Part, Coastal Processes and Physical Oceanography), which
may affect the distribution of eggs and larvae (Johnson et al. 2008). However,
a study of turbines in Danish waters found little to no impact on native
benthic communities and sediment structure from a change in hydrodynamic
regimes (DONG Energy et al. 2006). Studies conducted at wind
farms in the North Sea did not find significant changes in the benthic
community structure that could be related to changes in the hydrodynamics as a
result of the placement of in-water wind turbine structures (DONG Energy
et al. 2006). See Chapter 2, Ecology of the SAMP Region for
more information on physical oceanography and primary production in the Ocean
SAMP area.
6. The installation and
burial of submarine cables can cause temporary habitat destruction through
plowing trenches for cable placement, and may cause permanent habitat
alteration if the top layers of sediment are replaced with new material during
the cable-laying process, or if the cables are not sufficiently buried within
the substrate. Likewise, cable repair or decommissioning can impact benthic
habitats. The effect of the cables will depend on the grain size of sediments,
hydrodynamics and turbidity of the area, and on the species and habitats
present where the cable is being laid. Cables are usually buried in trenches 2
m (6.6 feet) wide and up to 3 m (9.8 feet) in depth (OSPAR 2008). Disturbance
to the seabed during cable-laying may also result from anchor and chain damage
from the installation barge, as the barge will have to repeatedly anchor along
the length of the cable route (MMS 2007b). In addition, sediments disturbed in
the cable-laying process may contain contaminants, and these may be dispersed
in the process. However, most contaminated sediments are likely to be found
close to the coast, unless the cable route passes close to a disposal site
(BERR 2008).
7. In many cases, the
seabed is expected to return to its pre-disturbance state after cable
installation. The extent of the impacts from cable laying may depend on the
amount of time it takes for the natural bathymetry to recover.
Post-construction monitoring may be used to track the recovery of a project
site. On rock or other hard substrates where the seabed may not recover easily,
backfilling may be required, or else permanent scarring of the seabed may
result. Scars along the bottom may impact migration for benthic animals.
Species found in rock habitats tend to be sessile (permanently attached to a
substrate), either encrusting or otherwise attached to the rock, and are
therefore more susceptible to disturbance (BERR 2008). Clay, sand, and gravel
habitats are typically less affected. Undersea cables can also cause damage to
benthic habitat if allowed to "sweep" along the bottom while being placed in
the correct location (Johnson et al. 2008). Initial
re-colonization of the site by benthic invertebrates takes place rapidly,
sometimes within a couple of months (BERR 2008). In deeper waters, where
disturbance of the seabed occurs with less frequency, recovery to a stable
benthic community can take longer than in shallow waters, sometimes years.
Generally, the effect on the benthic ecology will not be significant if the
cabling is done in areas where the habitat is homogenous. However, if the
cabling activity takes place in areas of habitat that are rare or particularly
subject to disturbance, the effects could be greater (BERR 2008). The most
serious threats are to submerged aquatic vegetation, which serves as an
important habitat for a wide variety of marine species. Shellfish beds and
hard-bottom habitats are also especially at risk (Johnson et
al. 2008). Shellfish in particular are usually not highly mobile, and
cannot relocate during the cable-laying process. Biogenic reefs made up of
mussels or other shellfish may become destabilized if plowing for cable-laying
damages the reefs (BERR 2008).
8.
The magnitude of the habitat disturbance effects depends on the duration and
intensity of the disturbance, and on the resilience of species living within
the sediment (Gill 2005). The expected effects are a local loss of sedentary
fauna living in the substrate, with mobile bottom-dwellers being displaced from
the area (Gill 2005). During the construction and decommissioning phases of a
project, the eggs and larvae of many fish species may be vulnerable to being
buried or removed. After the activity has ceased, recolonization may take
months or years (Gill 2005). Studies conducted on Danish wind farms found the
effects on benthic communities from burial by sediment were minimal when
monopiles were used, and the effects were both temporary and had limited
spatial distribution. Effects to the benthic community were limited primarily
to the area immediately surrounding the pile driving activity (DONG Energy
et al. 2006). Studies of the effects of sediment displacement
from cable laying found macro algae and benthic infauna were still recovering
two years after the activity had ceased (DONG Energy et al.
2006).
9. The recovery period, or
the time required for an area disturbed by construction related activities to
return to its pre-construction state, will vary between sites. For example,
research on the effects of trawling on the seabed have found that benthic
communities in habitats already subject to high levels of natural disturbance
will be less affected by trawling disturbance than more stable communities
(Hiddink et al. 2006). Typically, habitats such as coarse
sands are in general more dynamic in nature and therefore recover more rapidly
after disturbance than more stable habitat types where physical and biological
recovery is slow (Dernie et al. 2003). Disturbance from the
construction of wind turbine towers and laying cable is likely to produce
similar results. A few studies of dredging found that recovery times are
roughly six to eight months for estuarine muds, two to three years for sand and
gravel bottoms, and up to five to ten years for coarser substrates (e.g. Newell
et al. 1998).
10.
See below for the potential effects of benthic habitat disturbance on Ocean
SAMP area species including birds, sea turtles, marine mammals, and fisheries
resources.
D. Reef
effects (formerly § 850.3.2)
1. Offshore
renewable energy development, especially offshore wind development, will result
in the presence of man-made structures in the water column and on the seafloor.
These hard structures, such as the foundation structures and scour protection
devices, will introduce new habitat into the area that did not previously
exist. In this way, wind turbine structures may serve as artificial reefs, in
providing surfaces for non-mobile species to grow on and shelter for small fish
(Wilhelmsson et al., 2006). Any man-made structure in the
marine environment is usually rapidly colonized by marine organisms (Linley et
al., 2007). Fouling communities will colonize the hard structure and will
create new pathways for nutrients to be moved from the water column to the
benthos (Gill and Kimber 2005). Once a structure such as a wind turbine has
been erected, it increases the heterogeneity of the habitat. The physical
structure represents more colonization opportunities for invertebrates, as they
have more surface area. This in turn increases the number of food patches
available, as food resources generally are not uniformly distributed in coastal
waters (Gill and Kimber 2005). This will cause a fundamental shift in the
overall food web dynamics of the ecosystem, and may result in further shifts in
benthic community diversity, biomass and organic matter recycling (Gill and
Kimber 2005). Because some European offshore renewable energy facilities have
been closed to fishing activity (see § 8.4.8 of this Part, Commercial and
Recreational Fishing), the ecological effects observed in these facilities may
be in part due to decreased fishing disturbances. Researchers in the North Sea
(DONG Energy et al., 2006) found that a reduction in fishing
activity complicates their ability to assess ecological change from wind farm
development; there is no good information for ecosystem functioning prior to or
without fishing activity impacts and therefore difficult to establish any
cause-and-effect.
2. In places
where the wind turbines are under threat from erosion, large boulders are often
used as scour protection; these also serve as an artificial reef of their own
(Petersen and Malm 2006). Scour protection also provides hard surfaces for
colonization by fouling communities, as well as providing crevices and
structural complexity likely to attract fish and invertebrate species seeking
shelter (MMS 2007b).
3. It has been
found that although colonizing communities on offshore structures may vary
depending on geographic location and a number of other factors after initial
colonization, the differences are likely to decrease over the years as more
stable communities develop (Linley et al. 2007). Colonizing
communities will develop through the process of succession, where early
colonizing species are subsumed by secondary colonizers, leading to what is
known as the climax community, or the stable end point in the colonization
process. It may take five to six years for the climax community to develop at a
given site (Whomersley and Picken 2003, in Linley et al.
2007).
4. The changes likely to be
brought about by the reef effect of the turbines are not universally considered
to be beneficial. The changes in abundance and species composition could
degrade other components of the system, potentially pushing out other species
found in the particular habitat where construction is taking place. In
particular, this could affect vulnerable or endangered species through factors
such as loss of habitat, increased predation, or increased competition for prey
as the composition of the benthic community shifts to that of a hard bottom
community (Linley et al., 2007).
5. The diversity and biomass of the colonized
structures will depend in part on the choice of material, its roughness
(rugosity), and overall complexity. Concrete attracts benthic organisms;
however, when used in sub-marine construction, it is often coated with silane
or silicone, which deters the settling of organisms. Smooth steel monopiles,
which are often painted, tend to attract barnacles (Balanus improvisus) and
filamentous algae (Petersen and Malm 2006). The scaffolding used for oil and
gas rigs provides more structural complexity than monopile foundations; the
same is likely to be true for a jacketed structure for a wind turbine. These
rougher, complex structures offer more protection from predators and from high
velocities and scour (MMS 2009a).
6. Another factor influencing the
colonization of wind turbine structures will be the orientation of the
structures to the prevailing currents. Current speed and direction can
influence food availability, oxygen levels and the supply of larval recruits to
an area. As a result, structures more exposed to local currents may be more
colonized than other installations within the facility. Furthermore, structures
with more complex shapes will offer a greater range of localized hydrographic
conditions, offering more potential for colonization and greater biodiversity
(Linley et al. 2007). Colonization of structures will be
dependent on sufficient numbers of larvae present in the area, and on suitable
environmental conditions (Linley et al. 2007).
7. Often barnacles are the first colonizers
of the intertidal zone, while algae such as red seaweeds and kelp, along with
mussels, will dominate colonization starting at 1 to 2 meters below the
surface. Colonies based on mussels will also attract scavengers such as
starfish and flounder. In addition to mussels, some structures may instead be
colonized by a grouping of species including anemones, hydroids, and sea
squirts. The larvae present in the water column will vary depending on the time
of year, so colonization may be dependent on the time of year in which the
structures are erected. Community structure will also be dependent on the
presence of predators and on secondary colonizers (Linley et
al. 2007). Other species found within the Ocean SAMP area that are
likely to be early colonizers include algae, sponges, and bryozoans, and other
secondary colonizers are likely to include polychaetes, oligochaetes,
nematodes, nudibranchs, gastropods, and crabs (MMS 2009a). These substantial
colonies of invertebrates will attract fish to the structures, resulting in a
reef effect around the support structures. For more on reef effects and the
attraction of fish, see § 8.4.7(G) of this Part below.
8. Studies conducted in Denmark (Dong Energy
et al. 2006) at two wind farms sites (Nysted, 76 turbines; Horns Rev, 80
turbines) has shown major changes in community structure of the offshore
ecosystem from one based on infauna, or invertebrates that live within the
substrate, to that of a hard bottom marine community and a commensurate
increase in biomass by 50 to 150 times greater.
9. Wind turbines in the Baltic Sea built on
monopiles are almost entirely encrusted with a monoculture of blue mussels
(Mytilus edulis), which may be the result of a lack of predation and
competition from other species (Petersen and Malm 2006), as well as from low
salinity in the area where the turbines have been constructed. Mussels provide
a hard substratum used by macroalgae and epifauna, and therefore have the
potential to induce further change in the ecosystem by providing more surface
area for colonization. Colonization of wind farms will be determined partly
through zonation, the distribution of various communities of organisms at
different depths in the water column. A study of the Nysted offshore wind farm
found high concentrations of blue mussels on the wind turbine foundations, with
mussel biomass increasing closer to the surface, although in the highest
zonation, in the upper one meter of depth, the foundation was instead colonized
by barnacles. The biomass of barnacles was determined, through modeling
techniques, to be seven to eighteen times higher on the foundation close to the
surface than on the scour protection. The extent to which these mussels serve
as an artificial reef and increase productivity and biomass will depend on the
ecosystem feedback between the mussel colonies and the pelagic and benthic
environments around them, such as whether other invertebrates colonize the
mussels, and whether fish and other animals utilize these colonies for food and
shelter (Maar et al. 2009). On oil and gas platforms in
California, the structures are encrusted with mussels, at least at depths above
100 feet (30.5 m); as mussels are knocked off the platforms and accumulate at
the bottom, they create shell mounds on the seafloor which provide a secondary
habitat for fish and other species (Love et al.
2003).
10. A study of the effects
of the Horns Rev wind farm in Denmark found a shift in the benthic community
from the indigenous infaunal community to an epifouling community associated
with hard bottom habitats as both the monopiles and the scour protection were
colonized by algae and invertebrates. Two species of amphipods (Jassa marmorata
and Caprella linearis) were the most abundant species found on the turbines,
and a total of seven species of invertebrates, including the two amphipods, the
common mussel (Mytilus edulis), a barnacle species (Balanus cretanus), the
common starfish (Asteria rubens), the bristle worm (Pomatoceros triqueter), and
the edible crab (Cancer pagurus) made up 94% of the total biomass on the
structures. There were also eleven taxa of seaweeds found on the monopiles and
the scour protection. The monopiles and scour protection were found to be
hatchery or nursery grounds for a number of invertebrates, including crabs. The
wind turbine substructure and scour protection were found to house two species
of worms new to this area, and considered threatened elsewhere in the region.
The result of this new community has been an estimated 60-fold increase in the
availability of food for fish and other organisms in the area compared with the
original benthic community (Leonhard and Pedersen 2005). For information on the
potential future uses associated with the epifouling communities formed on
offshore wind energy turbines see Chapter 9, Other Future Uses.
11. Conversely, one study conducted at the
Nysted offshore wind farm in Denmark, found an overall decline in biomass
measured over three years. The encrusting community at this site had evolved to
become almost a monoculture of mussels. This particular area is brackish; the
lack of sea stars, an important mussel predator, was attributed to the low
salinity. Similar changes were observed at a test site; it was concluded that
these were the result of natural variations rather than an effect of the wind
turbines (MMS 2007b).
12. If scour
holes form in the sea bed adjacent to the turbines, these holes may be
attractive habitat to species such as crab and lobster, and to some fish
species, furthering the reef effect of the structures (Rodmell and Johnson
2002). For more on effects on scour and the physical oceanography of the Ocean
SAMP area from wind turbines, see § 8.4.2(E) of this Part.
13. If periodic cleaning of the encrusting
organisms on the structure base occurs, the community will be more or less
permanently in the early-colonization phase, and will not develop through
succession into a more mature climax community with greater biodiversity.
Instead, after each cleaning a new community will redevelop on the structure,
with the species composition varying based on the season, depending on which
larval species are present in the water column at the time. Moreover, if shells
are periodically removed, the discarded debris may attract scavenging animals,
and may serve to create new habitat on the seafloor where they accumulate
(Linley et al. 2007).
14. The reef effect is particularly relevant
to fisheries resources as well as other species groups; see sections on marine
mammals, fish, and sea turtles below for further
discussion.
E. Changes in
community composition (formerly § 850.3.3)
1. Wind energy and other offshore renewable
energy projects could have indirect ecological effects that could affect the
benthic community. A change in the type and abundance of benthic species can be
expected at the turbine sites, which will change food availability for higher
trophic levels. Studies of habitat disturbance resulting from fishing or
dredging activity have shown effects on local species diversity and population
density; the effects of offshore renewable energy projects are likely to be
similar (as suggested by Gill 2005). The magnitude of these effects depends on
the duration and intensity of the disturbance, and on the resistance and
resilience of species living within the sediment. The expected effects are a
local loss of sedentary fauna living in the substrate, with non-sedentary
bottom-dwellers being displaced from the area.
2. Because the placement of wind turbines
will increase habitat for benthic species, the structures will have the effect
of increasing local food availability, which may bring some fish and other
mobile species into the area. This may increase use of the area by immigrant
fauna. More adaptable species will probably dominate the area under these new
ecological conditions. The change in prey size, type, and abundance in the
vicinity of the structures may also affect predators. Predators moving into the
area may result in prey depletion (Gill 2005).
3. The PEIS (MMS 2007a) indicates that the
removal and deposition of benthic sediments associated with construction may
result in the smothering of some benthic organisms within the footprint of the
towers or along the cable route. Smothering would be a problem primarily for
sedentary invertebrates as most finfish and mobile shellfish would be expected
to move out of the way of incoming sediment (MMS 2007a). Studies conducted on
Danish wind farms found the impacts on benthic communities from burial by
sediment were minimal when monopile substructures were installed, and the
impacts were both temporary and had limited spatial impact (DONG Energy
et al. 2006). The recolonization of an area disturbed during
the construction process may take months or years (Gill 2005). Studies of the
impacts of sediment displacement from cable laying found macro algae and
benthic infauna were still recovering two years after the activity had ceased
(DONG Energy et al. 2006).
4. If fishing pressure is reduced in the
areas around the turbines as a result of fewer fishing vessels in the vicinity
of the turbines, this could have impacts on the community as a whole, both from
a reduction on fishing mortality of some species and a resulting increase in
predation by these species on others (MMS 2007b). For example, in the Horns Rev
wind farm, an increase in bivalves and worms inside of the park was attributed
to a decline in predation from scoters (a waterfowl species), who were avoiding
the wind turbines (Leonhard and Pedersen 2005). At the Nysted wind farm in
Denmark, densities of sand eels were found to increase by 300 percent between
2002 and 2004. The increase was likely attributable to either a decrease in
sand eel predation, or a decrease in fishing mortality (Jensen et
al. 2004, in MMS 2007b).
5. There is also a possibility that invasive
species may colonize the structures (MMS 2007a). The disturbances caused by the
placement of new structures may make the area more susceptible to invasion by
non-native species (Petersen and Malm 2006). Monitoring at Denmark's Horns Rev
wind farm in 2004 found an invasive species of tube amphipod, Jassa marmorata,
not previously seen in Denmark, to be the most abundant invertebrate found on
hard bottom substrate in the area (DONG Energy and Vattenfall 2006).
6. Didemnum spp., a particularly aggressive
invasive tunicate (sea squirt) of unknown origin, arrived in the New England
region in the late 1980s and has become firmly embedded in the aquatic
community from Eastport, ME to Shinnecock, NY (Bullard et al.
2007). There are no known, consistent predators of this species, which grows
rapidly on hard structure to depths of 80 m (262.5 feet). This sea squirt could
be problematic on new subsurface structures placed in the Ocean SAMP area,
potentially colonizing the structure and competing with native species for
planktonic food resources. Furthermore, this species is known to be able to
regenerate entire individuals from fragments (Bullard et al.
2007), such as might be formed during maintenance procedures to control
biofouling on wind turbine support structures, for instance. Didemnum is known
to grow particularly well in areas that are well-mixed (Valentine et
al. 2007); it is unknown if the turbulence created downstream of
subsurface structure, wind turbine pilings for instance, would further promote
conditions that favor this organism. See Chapter 2, Ecology of the SAMP Region
for more information on invasive species in the Ocean SAMP area.
7. One study of the North Hoyle wind farm in
the UK found that variability in benthic organisms taken from surveys around
the wind farm pre- and post-construction was more likely related to natural
variability, such as localized sediment composition, than to any effects caused
by the construction or operation of the wind farm (NWP Offshore Ltd.
2007).
8. The decommissioning of
wind turbines would also have significant ecological effects, as the new
habitat and accompanying species are removed. Habitat heterogeneity would be
immediately reduced, removing a large component of the benthic community (Gill
2005).
9. In summary, the
significant human activity resulting from the wind turbines would be likely to
have significant effects upon the food web, but just what those effects are is
unknown.
10. See § 8.4.7(G) of
this Part below for the potential effects of changes in community composition
on fisheries and fishery resources.
F. Noise (formerly § 850.3.4)
1. Underwater noise may be generated during
all stages of an offshore renewable energy facility, including during
pre-construction, construction, operation and decommissioning. The potential
effects of noise from offshore renewable energy are especially a concern for
marine mammals and fish species (see §§ 8.4.5 and 8.4.7 of this Part)
It is not understood whether the noise generated in the construction,
operation, and decommissioning of a wind turbine array would have an effect on
invertebrate species in the benthic environment. Few marine invertebrates have
the sensory organs to perceive sound pressure, although many can perceive sound
waves (Vella et al. 2001 in MMS 2007b). Studies on the
potential impact of air guns on squid have found few behavioral or
psychological effects unless the organisms are within a few meters of the
source (MMS 2007b). If there is any effect to these species, it is likely to be
much less than any potential effects to fish or marine mammals (Linley
et al. 2007).
G. Electromagnetic fields (EMF) (formerly
§850.3.5)
1. Underwater transmission
cables used to carry the electricity from an offshore renewable energy facility
back to shore produce magnetic fields around the cables, both perpendicularly
and in a lateral direction around the cable. While the design of industry
standard AC cables prevents electric field emissions, magnetic field emissions
are not prevented. These magnetic emissions induce localized electric fields in
the marine environment as sea water moves through them. Furthermore, in AC
cables the magnetic fields oscillate, and thereby also create an induced
electric field in the environment around the cables, regardless of whether the
cable is buried. Thus the term electromagnetic field, or EMF, refers to both of
these fields (Petersen and Malm 2006). While EMF is primarily an issue for
fish, sharks and rays (see § 8.4.7 of this Part), some invertebrate
species, such as a variety of crustacean species, have demonstrated magnetic
sensitivity and could be affected by EMF. These animals may become disoriented;
it is not known whether this will have a small or a significant impact on these
animals, although the likely impact is believed to be small (BERR 2008). For
more information on the effects of electromagnetic fields, see § 8.4.8 of
this Part, Fish and Fisheries Resources.
2. If electromagnetic fields affect the
presence or behavior of species likely to colonize wind turbine structures,
this could have an effect on the potential reef effects of the structures.
However, the interaction between most invertebrates and EMF is not known, and
the existence of healthy communities of colonizing species on turbine
structures in Europe indicates EMF will not have a significant impact on at
least these species assemblages (Linley et al.
2007).
H. Water quality
impacts (formerly § 850.3.6)
1. Offshore
renewable energy facilities would result in increased vessel traffic through
the site characterization, construction, operation, and decommissioning phases.
The PEIS indicates that such an increase in traffic could increase the
likelihood of fuel spills as a result of vessel accidents or mechanical
problems, though it indicates that the likelihood of such spills is relatively
small (MMS 2007a). In addition, wastewater, trash, and other debris may be
generated at offshore energy sites by human activities associated with the
facility during construction and maintenance activities (MMS 2007a, Johnson
et al. 2008). The platforms may hold hazardous materials such
as fuel, oils, greases, and coolants. The accidental discharge of these
contaminants into the water column could affect the water quality around the
facility; however these contaminants would likely remain at the surface and not
impact benthic ecosystems (MMS 2007a). In the PEIS, BOEM indicates that the
potential risk to water quality from offshore renewable energy development is
negligible to minor (MMS 2007a).
2.
Water quality may also be impacted during the construction process by
re-suspending bottom sediments, increasing the turbidity within the water
column. For the potential effects of water quality impacts on birds, marine
mammals, and fish, see sections below.
8.4.4 Birds (formerly § 850.4)
A. Offshore renewable energy
may have a variety of potential effects on avian species in the Ocean SAMP
area. Some effects may be negative, resulting in adverse impacts, other effects
may be neutral, producing no discernible impacts, while others may be positive,
resulting in enhancements. The purpose of this section is to provide an
overview of all the potential effects of offshore renewable energy development
on birds, including the potential for habitat displacement or modification;
disturbances associated with construction activities and/or vessel traffic;
avoidance behavior or changes in flight patterns; risk of collision with
installed structures; the risk of exposure to pollutants accidentally
discharged during construction, operation or decommissioning. Potential affects
to birds in the Ocean SAMP area will vary based on the species, as well as on
the particular site, and size of the project. The timing of construction or
decommissioning of an offshore renewable energy facility, along with the
cumulative impacts of other offshore developments will also have an effect on
the degree of impact.
B. Key to
measuring and understanding the effects of offshore renewable energy
development on avian species requires first sufficient baseline data on the
abundance, distribution, habitat use and flight patterns in the project area.
Baseline studies provide an important comparison point for assessing the
effects of pre-construction, construction, operation or decommissioning
activities. The duration of baseline studies may vary between project areas to
account for 'natural variability' observed in avian use of an area. Locations
that experience large fluctuations in avian densities over time may require
additional baseline monitoring to accurately assess pre-construction conditions
(Fox et al. 2006).
C. Research conducted by Paton et al. (2010)
for the Ocean SAMP has collected baseline data on species occurrence and
distribution in the Ocean SAMP area through land-based, ship-based and aerial
surveys, as well as through radar surveys from 2009 to 2010, although the exact
time period of surveys varied by survey technique. The goal of this research is
to assess current spatial and temporal patterns of avian abundance and movement
ecology within the Ocean SAMP boundary. Preliminary analysis of the surveys
conducted in nearshore habitats during land-based point counts from January
2009 to February 2010 recorded 121 species and over 460,000 detections in the
nearshore portion of the Ocean SAMP area (Figure 8.37 in §8.4.4(C)(1) of
this Part; Paton et al. 2010). Observations during these nearshore surveys have
demonstrated that a wide range of birds use the Ocean SAMP area, including
seaducks (e.g., eiders and scoters), other seabirds (e.g., loons, cormorants,
alcids and gannets), pelagic seabirds (e.g., storm petrel and shearwaters),
terns and gulls, shorebirds, passerines and other land birds (e.g., migrating
species and swallows). The most abundant bird species observed in nearshore
habitats in the Ocean SAMP area during land-based surveys were Common Eider
(Somateria mollissima), Herring Gull (Larus argentatus), Surf Scoter (Melanitta
perspicillata), Black Scoter (Melanitta nigra), Double crested Cormorant
(Phalacrocorax auritus), Tree Swallow (Tachycineta bicolor), Great Black-backed
Gull (Larus marinus), Laughing Gull (Leucophaeus atricilla), and the Northern
Gannet (Morus bassanus) (see Figure 8.37 in §8.4.4(C)(1) of this Part)
(Paton et al. 2010). Farther offshore, more pelagic species were detected
during boat-based surveys conducted from June 2009 to March 2010. During
boat-based surveys, which sampled eight 4 by 5 nm grids, 55 species were
detected from 10,422 detections (see Figure 8.38 in §8.4.4(C)(2) of this
Part). In offshore areas, Herring Gulls, Wilson's Storm-Petrels (Oceanites
oceanicus), Northern Gannets, Great Black-backed Gulls, White-winged Scoters
(Melanitta fusca) were among the most commonly detected species.
1. Figure 8.37: Most abundant species
observed in nearshore habitats of the Ocean SAMP study area based on land-based
point counts from January 2009 to January 2010 (Paton et al.
2010). (Note: Total detections = 465,039)
2. Figure
8.38: Most abundant species observed in offshore habitats based on ship-based
point counts in the Ocean SAMP study area from Mar 2009-Jan 2010 (Paton
et al. 2010).
D. Species distribution and abundance varied
both spatially and seasonally in the Ocean SAMP area. Most birds that use the
Ocean SAMP area are migratory, so that their occurrence is highly seasonal.
Paton et al. (2010) have found high inter-annual variability
in the abundance and distribution of avian species in the Ocean SAMP area,
suggesting that the collection of long-term baseline data prior to construction
and operation of an offshore renewable energy facility will be important in
examining any potential effects to avian species. For further discussion of the
findings of Paton et al. (2010) see Chapter 2, Ecology of the
SAMP Region.
E. In addition to
recording occurrence and abundance in the Ocean SAMP area, Paton et
al. (2010) have also identified potential foraging habitat for avian
species. Based on a literature review performed by Paton et
al. (2010) nearshore habitats, with water depths of less than 20 m [66
ft], are believed to be the primary foraging habitat for seaducks (see Table
8.13 in § 8.4.4(E)(1) of this Part). Figure 8.39 in § 8.4.4(F)(1) of
this Part illustrates the areas within the Ocean SAMP boundary with water
depths less than 20 m (66 feet) and therefore is thought to represent the
primary foraging habitat for the thousands of seaducks that winter in the Ocean
SAMP waters. Preferred sea duck foraging areas are strongly correlated with
environmental variables such as water depth, bottom substrate, bivalve
community, and bivalve density (Vaitkus and Bubinas 2001). Currently,
bathymetric data (water depth, bottom substrate) of the Ocean SAMP area is well
known, but relatively little is known about bivalve community and bivalve
density, especially further offshore. Foraging depths of seaducks differ among
species and are a function of preferred diet, but average depths tend to be
less than 20 meters (66 feet) for most species. Common eiders forage in water
less than 10 m (33 feet) during the winter when diving over rocky substrate and
kelp beds (Goudie et al. 2000; Guillemette et al., 1993).
Preferred diet of common eider changes with season and foraging location, but
mainly consists of mollusks and crustaceans (Goudie et al.
2000; Palmer 1949; Cottam 1939). Maximum diving depths of scoters are about 25
m (82 feet), although most birds probably forage in water less than 20 meters
(66 feet) deep, particularly during the winter months (Vaitkus and Bubinas
2001; Bordage and Savard 1995). Scoter diet in marine environments
predominantly consists of mollusks (Bordage & Savard 1995; Durinck
et al. 1993; Madsen 1954; Cottam 1939). Paton et
al. (2010) did detect seaducks in waters up to 25 meters (82 feet)
deep during aerial surveys, although it was unclear from the aerial surveys if
the seaducks were foraging or engaging in other behaviors such as roosting.
Paton et al. (2010) suggest more detailed research be
conducted to better understand the depths used for foraging by scoters or
eiders in the Ocean SAMP area.
1. Table 8.13:
Foraging depths of seaducks based on a literature review (Paton et
al. 2010).
|
Species |
Dive depth |
Source |
|
Common eider |
0-15 m ( 0-49 feet). |
Ydenberg and Guillemetter 1991 |
|
Surf Scoter - day |
90% of dives <20 m (66 feet) depth during diurnal period - used deeper waters at night - but rarely dived at night. |
Lewis et al. 2005 |
|
White-winged Scoter-day |
~90% of diver <20 m (66 feet) depth - used deeper waters at night - but rarely dived at night. |
Lewis et al. 2005 |
|
Black Scoter |
>95% of observations were in waters <20m (66 feet) deep. |
Kaiser et al. 2006 |
|
Common Eider |
100% <16 m (52.5 feet) deep. |
NERI Report 2006 |
|
Black Scoter |
100% <20 m (66 feet) deep. |
NERI Report 2006 |
F. Land-based surveys conducted by Paton et
al. (2010) support the findings of the literature review, as large
concentrations of seaducks (e.g. scoters and eiders) have been recorded in
these nearshore areas, particularly off Brenton Point (see Figure 8.39 in
§ 8.4.4(F)(1) of this Part). Because one potential effect of offshore
renewable energy development may include permanent habitat loss, identifying
and avoiding potentially important foraging habitat prior to siting future
projects may help to minimize any adverse impacts.
1. Figure 8.39: Potential foraging areas for
seaducks within and adjacent to the Ocean SAMP boundary (based on a literature
review by Paton et al. 2010)
2. Figure
8.40: Total number of detections for the most abundant guilds observed in
nearshore habitats during land-based point counts, Jan 2009-Feb 2010 (Paton
et al., 2010). (Note: Total Number of detections = 465,039;
Total Number of Species Recorded= 121)
G. When assessing the potential effects of
offshore renewable energy development, the impact on endangered or threatened
species are of particular concern, mainly because the magnitude of the
potential impact may be much more severe to these species due to their low
population numbers (MMS 2007a). The one federally-listed endangered bird using
the Ocean SAMP area is Roseate Tern (Sterna dougalli
dougalli). This species is a long-distance migrant that spends the
summer months in New England, including within the Ocean SAMP area (Paton et
al. 2010). Although this species does not nest in Rhode Island, there are
nesting colonies in Connecticut, New York, and Massachusetts that are close
enough that foraging adults from nesting colonies may use Ocean SAMP waters
(see Figure 8.41 in § 1.4.4(G)(1) of this Part). Terns may travel
substantial distances, 25.8 to 30.6 km [16 to 19 miles] from their breeding
locations to access foraging habitat, and therefore Roseate Terns may use
portions of the Ocean SAMP area (Paton et al. 2010). As of
2007, about 85% of the population was concentrated at Great Gull Island, NY
(1,227 pairs); Bird Island, Marion, MA (1,111 pairs); and Ram Island,
Mattapoisett, MA (463 pairs). There was a small colony (48 pairs) on Penikese
Island and 26 pairs nesting on Monomoy National Wildlife Refuge (Mostello
2007). Areas located in the northeast and northwest of the Ocean SAMP area lie
within the foraging range of the Roseate Tern, and may potentially be used by
for foraging adults.
1. Figure 8.41: Roseate
tern nesting locations in Southern New England (Paton et al. 2010).
H. In addition to foraging activity,
migrating Roseate Terns may also pass through the Ocean SAMP area on their way
to and from their nesting colonies (Harris 2009). Recent studies of
post-breeding staging by Roseate Terns documented 20 sites on Cape Cod where
Roseate Terns congregate in the fall before migrating south. Many uniquely
color-banded birds from Great Gull Island in NY at the western edge of the
Ocean SAMP area were located on Cape Cod (Harris 2009), thus it is probable
that many terns are migrating through the Ocean SAMP area in July and August,
but their migratory routes, the diurnal variation of this migration, and flight
elevations are uncertain. Paton et al. (2010) conducted
surveys specifically to record Roseate Tern use of the Ocean SAMP area during
summer (July, August), and detected relatively few birds during systematic ship
and land-based surveys (total detections equaled 29 and 125 observations
respectively). Alternatively, observations near Great Salt Pond on Block Island
during July and August of 2009 recorded relatively high numbers of individuals,
with up to 100 observations per day. It is believed that these birds are likely
individuals that breed in New York or Connecticut and are transiting through
the Ocean SAMP area; however more research is needed on post-breeding movement
of Roseate Terns (Paton et al. 2010).
I. The Piping Plovers (Charadrius melodus) is
another federally-listed species threatened species that nests on coastal
beaches in Rhode Island and on Block Island, adjacent to the Ocean SAMP area
(see Table 8.14 in § 8.4.4(I)(1) of this Part and Figure 8.42 in §
8.4.4(I)(2) of this Part). While there is uncertainty surrounding the migratory
routes taken by Piping Plovers, the U.S. Fish and Wildlife Service (1996)
presumes that the majority of the migratory movements of Atlantic Coast Piping
Plovers occur along a narrow flight corridor above the outer beaches of the
coastline. Moreover, inland and offshore migratory observations are rare (U.S.
Fish and Wildlife Service 1996). However, further investigation into Piping
Plover movements in a project area prior to construction would help minimize
the impact of avoidance behavior.
1. Table
8.14: 2009 Piping plover nesting sites (USFWS 2010)
|
Beach |
Nesting Pairs |
Chick Total |
|
Block Island |
2 |
0 |
|
Charlestown Beach |
0 |
0 |
|
East Beach Watch Hill |
22 |
53 |
|
East Matunuck |
1 |
2 |
|
Green Hill |
1 |
2 |
|
Napatree |
10 |
16 |
|
Narragansett Town Beach |
0 |
0 |
|
Narrow River |
2 |
4 |
|
Ninigret Conservation Area |
4 |
5 |
|
Ninigret NWR and Arnolda |
2 |
2 |
|
Norman Bird Sanctuary |
0 |
0 |
|
Sachuest Point National Wildlife Refuge |
1 |
0 |
|
Sandy Point |
2 |
4 |
|
Third Beach |
1 |
0 |
|
Trustom Pond National Wildlife Refuge |
12 |
9 |
|
Quonochontaug |
9 |
8 |
|
Total |
69 |
105 |
2.
Figure 8.42: Potential piping plover nesting sites adjacent to the Ocean SAMP
boundary (Data from U.S. Fish and Wildlife Service 2010)
J. Under Section 7 of the Endangered Species
Act all federal agencies are directed to consult with the U.S. Fish and
Wildlife Service (USFWS) to ensure that their actions do not jeopardize listed
avian species or, destroy or adversely modify critical habitat of such species.
If the USFWS determines that a federal action is likely to adversely affect a
species, formal consultation is required, and the issues are examined
thoroughly through the preparation of a Biological Assessment by the lead
federal agency and a Biological Opinion by the USFWS. Each addresses whether
any part of the proposed action is likely to jeopardize the existence of the
listed species, and may outline any necessary binding, and/or discretionary
recommendations to reduce impacts (MMS 2009a). Compliance with the ESA
regulations and coordination with the USFWS ensures that project activities are
conducted in a manner that greatly minimizes or eliminates impacting listed
species or their habitats (MMS 2007a). See Chapter 10, Existing Statutes,
Regulations and Policies for more information on the ESA.
K. Existing federal legislation also provides
protection to migratory bird species under the Migratory Bird Treaty Act and
the Migratory Bird Executive Order 13186. Consequently, when a proposed
offshore renewable energy project undergoes NEPA review, the USFWS will be
consulted to determine impacts to migratory species. As a result of the
Migratory Bird Executive Order 13186, BOEM (formerly the Minerals Management
Service) and USFWS have produced a Memorandum of Understanding that identifies
specific areas for cooperative action between the agencies and will inform the
review process of offshore wind energy facilities in federal waters, and
contribute to the conservation and management of migratory birds and their
habitats (MMS and U.S. Fish and Wildlife Service 2009). For more information on
the Migratory Bird Treaty Act and the Migratory Bird Executive Order 13186, see
Chapter 10, Existing Statutes, Regulations and Policies.
L. Past studies have shown that passerine
species use Block Island as a migratory stopover and also as a breeding area
(Reinert et al., 2002). Radar surveys on Block Island as part
of the research conducted by Paton et al. (2010) has supported these findings.
Preliminary analysis of radar data suggests that large numbers of passerines
are flying over the Ocean SAMP area, especially during the fall. Further
analysis of the radar data by Paton et al. (2010) will provide
some evidence of the directional movements, abundance and flight elevations.
Little is known regarding offshore passerine migration, though the work of
Paton et al. (2010) will provide greater insight into the use
of the Ocean SAMP area.
M. The
current understanding of the potential effects of offshore renewable energy
development on birds is based primarily on monitoring performed at European
offshore wind energy facilities, particularly Horns Rev and Nysted Offshore
Wind Energy Facilities in Denmark (see Table 8.15 in § 8.4.4(M)(1) of this
Part). It should also be noted that at three of the operational sites where
bird surveys have taken place (Horns Rev, Nysted and North Hoyle) bird numbers
were relatively low prior to construction. Therefore, while the overall
conclusions of these reports are useful in identifying potential effects, the
authors caution that the results may be applicable to other sites only on a
very general level (Petersen et al. 2006; Michel et al. 2007).
In addition to European reports, the Final Environmental Impact Statement for
the Cape Wind Energy Project, LLC (MMS 2009a) and the PEIS (MMS 2007a) have
also identified potential effects of offshore wind energy development to avian
species. Ultimately, the nature and magnitude of effects of offshore wind
energy development on marine and coastal birds depends on the specific location
of the facility and its transmission cable (e.g., proximity to nesting sites or
foraging habitat), the scale and design of the facility, and the timing of
construction-related activities (OSPAR 2006; MMS 2007a).
1. Table 8.15: Summary of European monitoring
of avian species.
|
Offshore Wind Energy Facility |
Survey Years |
Summary of Findings |
Citation |
|
Tuno Knob, Denmark: 10 turbines; online since 1995 |
1994-1997 1998-1999 |
Displacement/Changes in Distribution: Common Eiders declined by 75% and Black Scoters* by more than 90% during post-construction Flight Activity/Avoidance: Nocturnal flight activity of eiders and scoters occurred within and near the project site Nocturnal flight activity was 3-6 times greater on moonlit nights compared to dark nights Flight activity inside and in the vicinity the facility was lower than outside the facility |
Guillemette et al., 1998, 1999 Tulp et al. 1999 |
|
Nysted, Denmark: 72 turbines; online since 2004 |
1999-2005 |
Displacement/Changes in Distribution: Significant reduction in long-tailed duck staging in the project area post-construction Gulls and cormorants demonstrated attraction behavior to the structures within the facility Flight Activity/Avoidance: 91-92 % of all birds recorded avoided the offshore wind energy facility Lateral deflection averaged .5 km (0.3 miles) at night and 1.5 km (0.9 miles) or greater during the day Moderate reactions in flight routes were observed 10-15 km ( 6.2-9.3 miles) outside the facility For eiders, minor flight adjustments were made at 3 km (1.9 miles)and marked changes to orientation within 1 km of the facility Collision Risk: One collision was recorded using a Thermal Animal Detection System |
Dong Energy and Vattenfall 2006 |
|
Horns Rev, Denmark: 80 turbines; online since 2002 |
1999-2005 |
Displacement/Changes in Distribution: Loons and alcids avoided foraging and staging in the facility during construction Gulls demonstrated attraction behavior to the structures within the facility Flight Activity/Avoidance: Several species of seabirds showed avoidance of the facility and adjacent areas ( 2-4 km [1.2-2.5 miles]) post-construction, though this was not significantly different** There was a significant decrease in the percentage of loons using the area in the vicinity of the wind farm post-construction The number of scoters increased in the area near the wind farm post-construction; however, the distribution of scoters indicated they were avoiding the wind farm area, and were observed to avoid flying between the turbines Collision Risk: No collisions were observed |
Dong Energy and Vattenfall 2006 |
|
Utgrunden and Yttre Stengrund, Kalmar Sound, Sweden: 12 turbines total; online since 2001 |
1999-2003 |
Displacement/Changes in Distribution: Staging waterfowl declined throughout the study period Flight Activity/Avoidance: Eider spring migration paths were altered through the project area post-construction Lateral deflection occurred 1-2 km (0.6-1.2 miles) away from the facility (in good visibility) 15% of the autumn flocks and 30% of the spring flocks altered flight paths around facility Collision Risk: Out of the 1.5 million waterfowl observed migrating through Kalmar Sound, no collisions were observed |
Pettersson 2005 |
|
North Hoyle, U.K.: 30 turbines; online since 2003 |
2001-2004 |
Displacement/Changes in Distribution: Red-throated loon and cormorant shifted their distribution toward the wind park during construction Cormorant avoided the wind park during and after construction No significant change in distribution was observed in the common scoter, terns, guillemots, auks*** |
National Wind Power 2003 |
|
Blyth, U.K.: 2 turbines offshore, 9 turbines on the breakwater; offshore online since 2000; onshore online since 1993 |
1991-2001 |
Displacement/Changes in Distribution: No evidence of significant long-term displacement of birds from their habitats (either feeding areas or flight routes). Temporary displacement of cormorants was observed. Flight Activity/Avoidance: Approximately 80% of observed flight activity was below rotor height Gulls were the primary species flying at rotor height and feeding between turbines Collision Risk: Overall collision rate from 1991-2001 was 3% Eider collision rates declined over the monitoring period, suggesting adaptive behavior |
U.K. Department of Trade and Industry 2006 |
|
Kentish Flats, U.K. 30 turbines; online since 2005 |
2001-2005 |
Displacement/Changes in Distribution: No significant changes in abundance of bird population were observed between pre- and post-construction periods Though not statistically significant, observational data suggested that red-throated loons and great and lesser black-backed gulls decreased in abundance, and herring gulls increased in abundance at the study site Flight Activity/Avoidance: Observational data showed fewer common terns were observed flying through the facility (though not statistically significant) |
Gill, Sales, and Beasley, 2006 |
|
* Guillemette et al. 1998 and 1999 also found decreased scoter abundance in the control site. ** Authors stated that low overall bird numbers at the Horns Rev site, high variability between surveys and limited observations during poor visibility conditions prevented sufficient observance to assess avoidance. *** Authors stated that low overall bird numbers at North Hoyle made detecting changes in abundance difficult. |
|||
N. Habitat displacement or modification
(formerly § 850.4.1)
1. Offshore
renewable energy development may result in temporary or permanent habitat
displacement or modification during the construction, operation or
decommissioning of a facility. Depending on the location of the facility, birds
may potentially be displaced from offshore feeding, nesting, migratory staging,
or resting areas. Displacement may be caused by the visual stimulus of rotating
turbines, or the boat/ helicopter traffic associated with construction or
maintenance activities (Fox et al., 2006). Habitat loss or
modification on avian species may result in increased energy expenditures as
birds may need to fly farther to access alternate habitat (MMS 2009a).
Increased energy expenditures if severe may result in decreased fitness,
nesting success, or survival (MMS 2009a). Current research suggests that the
permanent loss of habitat, particularly foraging habitat, has the potential to
significantly impact certain avian species. However, the severity of the
effects of displacement from foraging habitat depends on the amount of habitat
lost, the distance to alternate habitat, and the food resources available at
the nearest alternate site (MMS 2009a). Siting offshore renewable energy
facilities in areas to avoid important bird foraging areas may minimize any
potential adverse impacts on birds (OSPAR 2006; MMS 2007a).
2. Changes in species distribution have been
observed at a number of offshore wind energy facilities in Europe. Studies of
the Horns Rev and Nysted wind farms in Denmark generally found birds to
demonstrate avoidance behavior of the wind farms, although the responses were
highly species specific. Diving ducks, in particular, avoided the turbines, and
few birds were observed in the area within the turbines (see Table 8.15 in
§8.4.4(M)(1) of this Part). This displacement of birds represents
effective habitat loss for a number of species, although it is important to
evaluate habitat loss in terms of the total proportion of feeding habitat
available (DONG Energy and Vattenfall 2006). One reported example of habitat
displacement was found to occur at the Nysted Offshore Wind Energy Facility in
Denmark. Long-tailed ducks (Clangula hyemalis) at this site
showed statistically significant reductions in density within and 2 km (1.2
miles) around the wind farm post-construction. Prior to construction the same
area had shown higher than average densities, suggesting that the facility had
resulted in the displacement of this species from formerly favored feeding
areas. However, the observed number of long-tailed ducks was relatively low and
therefore of no significance to the overall population (DONG Energy and
Vattenfall 2006).
3. At the Horns
Rev Demonstration Project, Red-throated and Arctic Loons (Gavia
stellata and Gavia arctica), Northern Gannets
(Sula bassana), Black Scoters (Melanitta
nigra), Common Murre and Razorbills (Uria aalge and
Alca torda) decreased their use of the wind farm area after
the installation of the wind turbines, including also zones of 2 and 4 km (1.2
and 2.5 miles) around the wind farm (DONG Energy and Vattenfall 2006). The
reason for this avoidance was unknown, though the researchers suggest that
perhaps disturbance effects from the turbines or from increased human activity
associated with maintenance of the facility may be possible reasons. However,
changes in the distribution of food resources in the study area may have also
played a role. In contrast, Herring Gulls (Larus argentatus)
showed a decreased avoidance of the wind farm area, while Great Black-backed
Gulls (Larus marinus), Little Gulls (Larus
minutus) and Arctic and Common Terns (Sterna paradisaea/hirundo)
showed a general shift from preconstruction avoidance to post construction
preference of the wind farm area. Gulls and terns recorded within the facility
were mainly observed at the edges of the wind farm and far less in the central
parts of the facility. The presence of the turbines and the associated vessel
activity in the area were suggested as possible reasons for increased use of
the project areas by the gulls (DONG Energy and Vattenfall 2006).
4. Additional evidence of displacement or
changes in distribution patterns of birds post-construction were reported in
the monitoring reports from Tuno Knob (eiders and scoters), Yttre Stengrund and
Utgrunden wind parks in Kalmar Sound (waterfowl), North Hoyle (shag, a species
of cormorant), Blyth (cormorant), and Kentish Flats (loons and gulls)
(Guillemette et al.1998; DONG Energy and Vattenfall 2006; Pettersson 2005;
National Wind Power 2003; U.K. Department of Trade and Industry 2006; Gill,
Sales, and Beasley 2006) though the statistical significance of displacement
varied widely among studies (Michel et al. 2007) (see Table
8.15 in § 8.4.4(M)(1) of this Part). Changes in distribution or
displacement of avian species from an area as a result of an offshore renewable
energy facility may be difficult to detect in some situations, especially when
there is a large annual or seasonal fluctuations in densities, or when prey
availability also varies spatially or temporally (Fox et al.
2006; Petersen et al. 2006).
5. Alternatively, changes in species
distribution in an area may result from the attraction to an offshore wind
energy facility. For species who do not avoid the project area, the reef
effects caused by the underwater structures of an offshore renewable energy
facility may increase prey availability. At the Nysted Offshore Wind Energy
Facility observations suggested that both Great Cormorants
(Phalacrocorax carbo) and Red-breasted Mergansers
(Mergus serrator) were attracted to the project site.
Cormorants were observed roosting on the meteorological masts and the
foundation of the turbines, suggesting that this species was not avoiding the
area but instead using the installed structures (DONG Energy and Vattenfall
2006). Observations of the Red-breasted Mergansers showed indications of an
increased preference of the wind farm site and peripheral areas (within 4 km
[2.5 miles]) after the installation of the wind farm. Increased fish
availability in the area in the post-construction phase was suggested as a
possible explanation for this increase (Petersen et al. 2006). For a more
detailed discussion of the potential for reef effects around offshore renewable
energy facilities see § 8.4.3(D) of this Part.
6. Temporary or permanent habitat
modification may result from construction activities such as foundation or
turbine installation, cable laying, or onshore installations. For example,
during construction periods, installation activities associated with
substructures and cable laying may increase temporarily the turbidity in the
project area. Increased total suspended solids may limit a birds' ability to
see under water and thereby search for food by sight, especially seaducks that
depend on benthic invertebrates as food. The Cape Wind FEIS predicts that
sediment suspended by the cable installation will be localized (within 457 m
[1,500 ft] of the trench) and may result in levels of 20 mg/liter. However, the
turbidity effects caused by cable laying and other construction related
activities will be highly site specific. Any impacts to turbidity are likely to
be localized and temporary (MMS 2009a).
7. Onshore construction associated with
offshore renewable energy development may result in the loss or alteration of
coastal habitat used by birds for foraging, roosting, nesting, migratory
staging or resting. While the impacts of habitat modification on most birds
would be expected to be temporary (lasting only until construction was
completed), modifications to some coastal habitats (e.g., near onshore
substations) may be long-term (MMS 2007a).
O. Human disturbance (formerly §
850.4.2)
1. Construction, operation and
decommissioning activities may cause a temporary or long-term disturbance to
birds in the vicinity of an offshore renewable energy facility, or in coastal
areas where underwater transmission cables are connected to the grid. Vessel
traffic, noise associated with pile driving or other construction of
above-water portions of the towers and the substation may result in the
disturbance of birds offshore. Affected birds would be expected to leave the
area during the construction period, and some may permanently abandon the area
due to the subsequent presence and operation of the completed offshore
renewable energy facility (MMS 2009a; Petersen et al., 2006).
One observed example of disturbance at the Horns Rev site involved a passing
service helicopter through an area outside of the wind farm where a
congregation of Black Scoters was present. The helicopter activity resulted in
a massive flush of birds which took to the air in avoidance. However, this
reaction was only temporary as most of the disturbed birds were recorded
landing in the same area after the helicopter had left (Petersen et
al. 2006). Onshore, coastal construction involved in connecting the
transmission cable to the grid, may disturb shorebirds in the area (MMS 2009a).
Particularly sensitive species, such as the Piping Plover, may be disturbed
from their nests or from foraging activities which may have consequences on
individual health or breeding success (MMS 2009a). Siting onshore transmission
cable connections away from known nesting habitats when possible and scheduling
onshore construction activities during non-breeding seasons may minimize any
potential adverse impacts to shorebirds.
P. Avoidance/flight barrier (formerly §
850.4.3)
1. Avoidance behavior or the
alteration of flight patterns may also result from the presence of an offshore
renewable energy facility, as studies have shown that some birds chose to fly
outside an offshore wind energy facility rather than fly between the turbines
(MMS 2007b; Fox et al., 2006; Petersen et al.
2006; Desholm and Kahlert 2005). Such avoidance behavior may reduce the risk of
collision, however the offshore wind energy facility may also present a barrier
to movement, increase distances to foraging habitats, or increase migratory
flight distances (Tulp et al., 1999, Kahlert et
al. 2004, Desholm and Kahlert 2005; Fox et al.,
2006). The level of impact may depend on the size of the facility, the spacing
of the turbines, the extent of extra energetic cost incurred by avoiding the
area (relative to the normal flight costs pre-construction) and the ability of
the bird to compensate for this degree of added energetic expenditure. In
extreme conditions, increased energy exerted by a bird to avoid a project site
may potentially result in a reduced physical condition (Fox et
al., 2006).
2. Avoidance
behavior and changes in flight orientation were reported for Tuno Knob (1 to
1.5 km [0.6 to 0.9 miles] from turbines), Nysted (0.5 to 3 km [0.3 to 1.9
miles] from turbines, and sometimes moderate adjustments were observed 10 to 15
km [6.2 to 9.3 miles] away), Horns Rev (0.2 to 1.5 km [0.1 to 0.9 miles]), and
Kalmar Sound (1 to 2 km [0.6 to 1.2 miles]) (Tulp et al. 1999;
DONG Energy and Vattenfall 2006; Pettersson 2005). Extra energetic costs as a
result of alterations to flight paths were calculated and considered to be
negligible at Nysted (0.5 to 0.7 percent) and Kalmar Sound (0.4 percent). In
addition, decreased numbers of migrant flocks were observed crossing Nysted,
Horns Rev, and the Kalmar Sound offshore wind energy facilities when compared
to baseline periods (DONG Energy and Vattenfall 2006; Pettersson 2005). To
date, all studies that have monitored lateral deflection of migrating flocks
reported active avoidance of turbines (Michel et al.
2007).
3. Researchers at Tuno Knob,
Nysted, Horns Rev, and Kalmar Sound also examined how the effect of reduced
visibility (at night or in poor weather conditions) affected flight patterns
around an offshore wind energy facility (Tulp et al. 1999;
DONG Energy and Vattenfall 2006; Pettersson 2005). The researchers concluded
that flight adjustments often were made closer to the edge of the wind park at
night or in low visibility conditions than during the day or in clear weather.
Observations using the Thermal Animal Detection Systems (TADS) at Nysted
provided infra-red monitoring over extended periods of nighttime and detected
no movements of birds below 120 m (393.7 feet) during the hours of darkness,
even during periods of heavy migration. This suggests birds flying in the
vicinity of the wind farm are doing so at higher altitudes at night (up to 1500
m (0.9 miles) altitude), and that even at heights above the rotor swept zone a
lateral response can be detected amongst night migrating birds (DONG and
Vattenfall 2006; Blew et al. 2006).
Q. Collision with structures (formerly §
850.4.4)
1. The risk of collision with
offshore renewable energy structures, such as offshore wind turbine blades and
towers, by birds is based on: the frequency of species occurrence in the
project area, visibility conditions during encounters with structures, and the
flight behavior or height of birds when in the vicinity of a facility (MMS
2009a, Petersen et al. 2006). Monitoring at European offshore wind energy
facilities has reported relatively few collisions, perhaps in part due to the
avoidance reaction many species exhibit prior to reaching the facility (Michel
et al. 2007).
2.
Out of a total 1.5 million migrating waterfowl observed during the monitoring
of the Swedish offshore wind energy facilities in Kalmar Sound, no collisions
were observed (Pettersson 2005). Similarly, no collisions were observed at the
Horns Rev facility throughout the monitoring period (2002-2005). While no
collisions were observed, the risk was modeled and predicted to equal
approximately 14 birds per year or 1.2 birds per turbine per year at Kalmar
Sound (Pettersson 2005).
3. At
Nysted thermal imaging equipment was mounted to a turbine during operation to
capture bird movement and collisions. One bird collision was recorded during
the 2005 monitoring period which covered all four seasons of that year.
However, the equipment was only stationed at one site, limiting the probability
of capturing a collision (DONG Energy and Vattenfall 2006). Because not all
turbines could be outfitted with thermal imaging equipment, a collision model
was used to estimate the numbers of Common Eiders, the most common species in
the project area, likely to collide with the sweeping turbine blades each
autumn at the Nysted offshore wind farm. Using parameters derived from radar
investigations and TADS, and 1,000 iterations of the model, it was predicted
with 95% certainty that out of 235,000 passing birds, 0.018 to 0.020% would
collide with all turbines in a single autumn (41 to 48 individuals), equivalent
to less than 0.05% of the annual hunt in Denmark (currently approximately
70,000 birds) (DONG Energy and Vatenfall 2006).
4. The collision rate at Blyth Offshore Wind
Energy Facility was more accurately measured since nine of the turbines are
located on a breakwater and the entire facility is relatively close to shore
and therefore more easily accessible. From 1991 to 1996, the collision rate was
calculated to equal less than 0.01 percent. During 10 years of monitoring (1991
to 2001), only three percent of the 3,074 bird carcasses collected were
directly attributed to collisions with turbines (Still et al.,
1996 as cited in Michele et al. 2007). Researchers suggested
that mortality events may have correlated with reduced visibility or poor
weather conditions. Eider collision rates declined during the monitoring
period, possibly because of adaptive behavior. Approximately 80 percent of
observed flight activity was below rotor height; gulls were the primary species
flying at rotor height and feeding between turbines.
5. Research conducted by Paton et
al. (2010) will provide baseline information on the frequency of
occurrence of different avian species in the Ocean SAMP area, as well as
information on the flight elevation of individuals traveling through the Ocean
SAMP area. This information will help to assess the risk of bird collisions in
the Ocean SAMP area if an offshore wind energy facility were to be
developed.
R. Water
quality (formerly § 850.4.6)
1. Water
quality around an offshore renewable energy facility may potentially be
impacted if illegal dumping or accidental spills occurs from vessels or
equipment. Because many marine and coastal birds follow behind vessels to
forage in their wake, individuals may be exposed to accidental discharges of
liquid wastes (such as bilge water, operational discharges). Dumping and oil
spills are already subject to standard operating procedures and discharge
regulations (30 C.F.R.
§
250.300 and MARPOL, Annex V, Public
Law 100-220 [101 Statute 1458]), and the discharge of any legally allowed waste
is not expected to pose any threat to avian species (MMS 2007a). Substances
that are legally discharged from vessels offshore are rapidly diluted and
dispersed posing negligible risk to birds in the area (MMS 2007a). Accidental
spills from offshore renewable energy facilities may pose a potential hazard to
birds if they result in the release of large volumes of hazardous materials
(MMS 2007a). For example, transformers, used to transmit energy generated from
the offshore renewable energy facilities to shore, may contain reservoirs of
electrical insulating oil or other fluids. The accidental release of these
materials may impact the health and survival of waterbirds exposed to the
spill, or may indirectly impact avian species by adversely affecting prey
species in the area (MMS 2009a). The severity of these impacts depend on the
location of the facility, the volume and timing of the spill, the toxicity of
the material and the species exposed to the spill (MMS 2007a; MMS 2009a). An
assessment performed on the Cape Wind Project found that the potential risk
associated with accidental spills is insignificant to minor, and that
precautionary measures such as developing an oil spill response plan may
minimize any adverse impacts on avian species (MMS 2009a).
2. If solid waste is released, marine and
coastal birds may become entangled in or ingest floating, submerged, and
beached debris, potentially resulting in strangulation, the injury or loss of
limbs, entrapment, or the prevention or hindrance of the ability to fly, swim
or ingestion food, or release toxic chemicals (Dickerman and Goelet 1987; Ryan
1988; Derraik 2002). These adverse impacts may potentially reduce the growth of
an individual or may be lethal in severe cases (MMS 2007a). Bird species
utilizing the Ocean SAMP area are already exposed to the potential risks
associated with marine debris resulting from existing uses of the Ocean SAMP
area.
8.4.5 Marine Mammals (formerly § 850.5)
A. Offshore renewable energy may have a
variety of effects on marine mammals in the Ocean SAMP area. The purpose of
this section is to provide an overview of all of the potential effects of
offshore renewable energy facilities on the marine mammal species that are
known to occur within the Ocean SAMP area. It should be noted that these
potential effects may vary widely depending on the species as well as the
particular site or project. In addition, it should be noted that scientific
inquiry into the interactions between offshore wind farms and marine mammals is
relatively new, and in most cases still under development. This section
provides an overview of the best information available to date. It is expected
that this section and the entire Ocean SAMP document will be updated in the
future, as new information is made available.
B. Understanding the responses of marine
mammals to offshore renewable energy facilities requires sufficient data on the
abundance, distribution, and behavior of marine mammals, which are difficult to
observe because they spend most of their time below the sea surface (Perrin
et al. 2002). Data on abundance in particular are difficult to
come by; there is a lack of baseline data for many species, and some of the
baseline data in use may be outdated. In order to understand the context in
which a specific development site is being used by target species (e.g., for
feeding, breeding or migration) baseline data should be collected before any
human activity has started (OSPAR 2008). A desk-based study conducted by Kenney
and Vigness-Raposa (2009) for the Ocean SAMP, has synthesized all available
information on marine mammal occurrence, distribution and usage of this area,
providing valuable background of the importance of this area to marine mammal
species. This report also ranks marine mammal species found within the Ocean
SAMP area according to conservation priority, taking into account such factors
as overall abundance of the population, the likelihood of occurrence in the
Ocean SAMP area, endangered or threatened status, sensitivity to specific
anthropogenic activities, and the existence of other known threats to the
population (Kenney and Vigness-Raposa 2009).
C. Marine mammal species in the Ocean SAMP
area are either whales (cetaceans), a scientific order which includes dolphins
and porpoises, or seals (pinnipeds). Marine mammals are highly mobile animals,
and for most of the species, especially the migratory baleen whales, the Ocean
SAMP area is used temporarily as a stopover point during their seasonal
movements north or south between important feeding and breeding grounds. The
Ocean SAMP area overlaps with the Right Whale Seasonal Management Area,
although the typical migratory routes for right whales and other baleen whales
lie further offshore and outside of the Ocean SAMP area (Kenney and
Vigness-Raposa 2009; see Chapter 7, Marine Transportation, Navigation and
Infrastructure). However, in one event in April 2010, nearly 100 right whales
were spotted feeding in Rhode Island sound, indicating that they do sometimes
appear within the Ocean SAMP boundary area (NEFSC 2010). Right whales and other
baleen whales have the potential to occur in the SAMP area in any season, but
would be most likely during the spring, when they are migrating northward and
secondarily in the fall during the southbound migration. In most years, the
whales would be expected to transit through the Ocean SAMP area or pass by just
offshore of the area.
D. While the
impact on any species of marine mammal within the vicinity of an offshore
renewable energy facility is important, endangered or threatened species are of
particular concern, mainly because the magnitude of the potential impact may be
much more severe to these species due to their low population numbers (MMS
2007a). The following marine mammals are of highest concern because they are
listed as endangered under the federal Endangered Species Act (ESA) and may
also occur within the Ocean SAMP area: the North Atlantic Right whale
(Eubalaena glacialis), the humpback whale (Megaptera
novaeangliae), and the fin whale (Balaenoptera
physalus). Other marine mammal species that occur commonly or
regularly within the Ocean SAMP area are listed in Table 8.16 in §
8.4.5(D)(1) of this Part. Three very abundant species that are likely to occur
frequently in the Ocean SAMP area include the Harbor Porpoise (Phocoena
phocoena), the Atlantic White-Sided Dolphin (Lagenorhynchus
acutus) and the Short-Beaked Common Dolphin (Delphinus
delphis) (Kenney and Vigness-Raposa 2009).
1. Table 8.16. Marine mammal species most
commonly occurring in the Ocean SAMP area (Kenney and Vigness-Raposa 2009)
|
Season Most Abundant in Ocean SAMP Area[DAGGER] |
Comments on Distribution or Activity in the Ocean SAMP Area |
|
|
North Atlantic Right Whale (E) |
Spring & Fall |
Mostly transits through outer regions of the Ocean SAMP area as individuals migrate south in the fall and north in the spring; occasionally individuals will linger for days or weeks to feed in Ocean SAMP area. |
|
Humpback Whale (E) |
Spring & Summer |
Abundance varies year to year in response to prey distribution. |
|
Fin Whale (E) |
Summer |
More abundant outside the Ocean SAMP boundary. |
|
Sperm Whale (E) |
Summer |
More abundant outside the Ocean SAMP boundary, primarily in deeper water. |
|
Harbor Porpoise |
Spring |
Can occur in the Ocean SAMP area during all seasons, but are most abundant in the spring when they are moving inshore and northeastward toward feeding grounds. They are among the most abundant marine mammal species within the Ocean SAMP area. |
|
Atlantic White-Sided Dolphin |
All seasons |
Most abundant outside Ocean SAMP boundary. |
|
Short-beaked Common Dolphin |
All seasons |
Likely to occur frequently in the Ocean SAMP area. |
|
Harbor Seal |
Fall, Winter and Spring |
Regular haul-out sites along the periphery of Block Island (October through early May). These haul-out sites are thought to be used primarily by younger animals that are foraging in the area prior to migrating further north. |
|
Sei Whale (E) |
Spring |
Irregular abundance in Ocean SAMP area. |
|
Common Minke Whale |
Spring and Summer |
More abundant outside the Ocean SAMP boundary. |
|
Long-Finned Pilot Whale |
Spring |
More abundant outside the Ocean SAMP boundary. |
|
Risso's Dolphin |
Spring and Summer |
More abundant outside the Ocean SAMP boundary. |
|
Bottlenose Dolphin |
Summer |
Likely only to be seen in outer part of Ocean SAMP area. |
|
[DAGGER]In many cases marine mammal species may be present in all seasons. Seasons listed are those with the greatest probability of occurrence. Seasons are defined as: Winter (December, January, February); Spring (March, April, May); Summer (June, July, August); Fall (September, October, November) (E) Marine Mammal is listed as Endangered under the Endangered Species Act |
||
E. The only species that can be classified as
a seasonal resident marine mammal in the Ocean SAMP area is the Harbor Seal
(Phoca vitulina). Harbor seals are known to regularly occupy
haul-out sites on the periphery of Block Island (along with other sites outside
of the Ocean SAMP area within Narragansett Bay) during the winter and early
spring (Kenney and Vigness-Raposa 2009). The haul-out site used most frequently
on Block Island is a wooden raft located in Cormorant Cove within the Great
Salt Pond, located near the center of the island (See Figure 8.43 in
§8.4.5(E)(1) of this Part) (Kenney and Vigness-Raposa 2009; Schroeder
2000). Because the site is at the center of the island, it is unlikely to be
disturbed by activities associated with the development of offshore renewable
energy.
1. Figure 8.43. Seal haul-out sites
in the Ocean SAMP area (Schroeder 2000; Kenney and Vigness-Raposa 2009).
F. The degree to which offshore renewable
energy facilities may affect marine mammals depends in large part on the
specific siting of a project, as well as the use of appropriate mitigation
strategies to minimize any adverse effects (MMS 2007a). All potential adverse
impacts and enhancements posed by any future project within the Ocean SAMP area
to marine mammals will undergo rigorous review under the National Environmental
Policy Act (NEPA) to comply with the standards under the Marine Mammal
Protection Act (MMPA) and the Endangered Species Act (ESA). Under the MMPA all
marine mammals are protected, and acts that result in the taking (a take is
defined as "harass, hunt, capture, collect, or kill, or attempt to harass,
hunt, capture, collect, or kill any marine mammal") of marine mammals in U.S.
waters is prohibited without authorization from the National Marine Fisheries
Service (NMFS). Further protection is granted under the ESA by the NMFS for
marine mammals that are listed as threatened or endangered. The ESA prohibits
any person, including private entities, from "taking" a "listed" species.
"Take" is broadly defined as "to harass, harm, pursue, hunt, shoot, wound,
kill, trap, capture or collect or to attempt to engage in any such conduct." As
a result, any proposed project will require consultation under the ESA and MMPA
to examine all potential effects on marine mammals prior to development in
order to ensure that potential adverse impacts are minimized. For more
information on the MMPA and the ESA see Chapter 10, Existing Statutes,
Regulations, and Policies.
G. The
principle impacts identified in the PEIS include potential effects of increased
underwater noise, impacts to water quality, vessel strikes and displacement
(MMS 2007a). Of these potential impacts, increased underwater noise may pose
the greatest risk to marine mammals, especially to baleen whales (e.g. humpback
whales and the North Atlantic right whale), who are in theory most sensitive to
the low frequency sounds produced during construction activities (see below for
further discussion).
H. Noise
(formerly § 850.5.1)
1. Marine mammals
have highly-developed acoustic sensory systems, which enable individuals to
communicate, navigate, orient, avoid predators, and forage in an environment
where sound propagates far more efficiently than light (Perrin et
al. 2002) Evaluating noise effects on marine mammals can be
challenging, as information on hearing sensitivity for most marine mammal
species is currently not available (Richardson et al. 1995;
Southall et al. 2007). As a result, when analyzing potential
noise effects from offshore renewable energy installations, the hearing
sensitivities of most marine mammal species need to be inferred.
2. In principle, marine mammals can be
expected to be most sensitive to sounds within the frequency range of their
vocalizations (Richardson et al. 1995). For example, baleen
whales produce low frequency sounds (~10Hz to 10 kHz), that travel long
distances under water, and therefore, it is expected that these whales would
also be most acoustically sensitive at lower frequencies (Richardson et
al. 1995). However, there is no data on hearing sensitivities in any
baleen whale species to date, making assessments on noise effects quite
difficult. It is known that smaller toothed whales can hear frequencies over a
range of 12 octaves, with a hearing range that overlaps the frequency content
of their echolocation clicks and their vocalizations used for communication
(Hansen et al. 2008; Au 1993; Richardson et
al. 1995; Southall et al. 2007). In addition, as with
any mammal, hearing sensitivity varies between individuals within a species
(Houser and Finneran, 2006). Consequently, as a result of the incomplete data
on marine mammal hearing, it can be difficult to predict the potential impact
of noise from offshore renewable energy facilities on marine mammal species.
There have been a number of studies conducted in Europe on the effects of pile
driving as well as the effects of noise from operating wind farms on marine
mammals. However, Europe has very few species of marine mammals, and only rare
occurrences of baleen whales in the wind farm areas, leaving significant data
gaps in the noise effects of offshore wind energy on marine mammals.
3. Underwater noise may be generated during
all stages of an offshore renewable energy facility, including during
pre-construction, construction, operation and decommissioning. The strength and
duration of the noise varies depending on the activity (see Table 8.17 in
§8.4.5(H)(3)(a) of this Part). For example, some construction activities,
such as pile driving, result in short periods of intense noise generation,
compared with long-term, low level noise associated with operational
activities. While the intensity and duration of the noise produced by pile
driving activities and operational wind turbines vary, both produce low
frequency noise, and therefore potentially pose a risk in particular to large
whales, such as the North Atlantic right whale, humpback whales, and fin
whales, as these species are thought to be most sensitive in this frequency
range (Southall et al. 2007; see Figure 8.44 in
§8.4.5(H)(3)(b) of this Part). In order to minimize the risk of causing
hearing impairment or injury to any marine mammal during activities of high
noise, monitoring the project area for the presence of marine mammals and
maintenance of an exclusion zone has been required (MMS 2009a; JNCC 2009).
Furthermore, scheduling construction activities to avoid periods when marine
mammals may be more common in the project area is one precautionary measure to
minimize any potential adverse impacts (OSPAR 2006). Information on the
potential long-term impacts of displaced individuals, or on the potential
effects under water noise may cause to resident marine mammal populations, is
not currently available (MMS 2007a, OSPAR 2008).
a. Table 8.17: Above and below water noise
sources associated with offshore renewable energy development (MMS 2007a; OSPAR
2009a)
|
Above Water Noise |
|||||
|
Noise Source |
Duration |
Frequency Range |
Frequency of Peak Level (Hz) |
Peak Sound Intensity Level (dB re-20 µPa) |
Reference Distance (m) |
|
Ship/barge/ boata,b,d |
Intermittent to continuous, up to several hours or days |
Broadband, 20-50,000 Hz |
250-2,000 |
68-98 |
Near source |
|
Helicopter |
Intermittent, short duration |
Broadband with tones |
10-1,000 |
88 |
Near source |
|
Pile driving a,d |
50-100 millisecond pulses/beat, 30-60 beats/min, 1-2 hours/pile |
Broadband |
200 |
110 |
15 m (49.2 feet) |
|
Construction equipmentd |
Intermittent to continuous |
Broadband |
Broadband |
68-99 |
15 m (49.2 feet) |
|
Underwater Noise Sources |
|||||
|
Noise Source |
Duration |
Frequency Range |
Frequency of Peak Level (Hz) |
Peak Sound Intensity Level (dB re-1 µPa) |
Reference Distance (m) |
|
Ship/barge/ boata,b,c,,f |
Intermittent to continuous, up to several hours or days |
Broadband, 20-50,000 Hz |
250-2,000 |
150-180 rms |
1m (3.3 feet) |
|
**Pile drivinga,d,f |
50-100 millisecond pulses/beat, 30-60 beats/min, 1-2 h/pile |
Broadband, 20- above 20,000 Hz |
100-500 |
228 peak, 243-257 peak to peak |
1m (3.3 feet) |
|
Seismic air-gun array b,f |
30-60 millisecond pulses, repeated at 10 -15 sec intervals |
Mainly low frequency, but some 10-100,000 Hz |
10-125 |
Up to 252 downward, up to 210 horizontally |
1m (3.3 feet) |
|
Seismic explosions TNT ( 1-100lbs)e,f |
~ 1-10 milliseconds |
2-1,000 Hz |
6-21 |
272-287 |
1m (3.3 feet) |
|
Dredging c,f |
Continuous |
Broadband, 20-20,000 Hz |
100-500 |
150-186 |
1m (3.3 feet) |
|
Drilling b,c,f |
Continuous |
Broadband, 10-10,000 Hz |
20-500 |
154 |
1m (3.3 feet) |
|
Operating Turbine (1.5 MW operating in winds of 12 m/s) a |
Continuous |
50 Hz/ 150 Hz |
120-142 |
1m (3.3 feet) |
|
|
a Thomsen et al. (2006) b LGL (1991) c Richardson et al. (1995) d Washington DOT (2005) e Ross (1976) f OSPAR (2009a) **(note: noise associated with pile driving will vary greatly depending on the size of the pile and hammer used) |
|||||
b.
Figure 8.44: Typical frequency bands of sounds produced by marine mammals
compared with the main frequencies associated with offshore renewable energy
development (OSPAR 2009a).
4. When examining acoustic impacts on marine
mammals, four overlapping impact zones are commonly used (see Figure 8.45 in
§8.4.5(H)(4)(a) of this Part; Richardson et al. 1995),
corresponding to the different effect levels: the zone of hearing loss,
discomfort, or injury, the zone of responsiveness, the zone of masking and, the
zone of detection/ audibility. The zone closest to the sound source usually has
the highest sound levels, which may result in physical damage or injury to a
marine mammal if sound levels are sufficiently high (OSPAR 2009a). In the zone
of responsiveness, noise exposure may result in behavioral reactions such as
avoidance, disruption of feeding behavior, interruption of vocal activity or
modifications of vocal patterns. In the zone of masking, the overlap in the
frequencies of sounds produced by a sound source and those used by marine
mammals has the potential to mask vocalizations, interfering with their
reception and inhibiting the efficient use of sound. The detection zone is the
area in which the noise generated from the sound source is audible to a marine
mammal, and above ambient noise levels (Richardson et al.
1995).
a. Figure 8.45: Theoretical zones of
noise influence (Richardson et al. 1995).
5. Regarding the impacts of offshore
renewable energy construction on marine mammals, the MMPA considers the zone of
physical impairment, responsiveness and masking when determining a proposed
project's compliance. Under the MMPA: "Level A Harassment means any act of
pursuit, torment, or annoyance which has the potential to injure a marine
mammal or marine mammal stock in the wild. Level B Harassment means any act of
pursuit, torment, or annoyance which has the potential to disturb a marine
mammal or marine mammal stock in the wild by causing disruption of behavioral
patterns, including, but not limited to, migration, breathing, nursing,
breeding, feeding, or sheltering but which does not have the potential to
injure a marine mammal or marine mammal stock in the wild." See Table 8.18 in
§8.4.5(H)(5)(a) of this Part for the criteria used to define Level A and
Level B affects under the MMPA.
a. Table
8.18: Criteria for estimating the effects of noise on marine mammals under the
Marine Mammal Protection Act (U.S. Department of Commerce 2008).
|
Criteria |
NMFS Criteria |
|
Level A Injury (Pinnipeds) |
190 dB re 1 µPa rms (impulse, e.g. pile-driving) |
|
Level A Injury (Cetaceans) |
180 dB re 1 µPa rms (impulse) |
|
Level B Harassment/Behavior |
160 dB re 1 µPa rms (impulse) |
|
Level B Harassment/Behavior |
120 dB re 1 µPa rms (non-pulse noise, e.g. vibratory pile driving) |
6. Prior to construction, geophysical surveys
performed to characterize ocean-bottom topography or geology may include the
use of air gun arrays or side-scan sonar. Survey techniques using high-energy
air gun arrays pose a greater risk to marine mammals in the vicinity of the
sound source, as opposed to side-scan sonar, and may result in temporary
hearing impairment or in extreme cases physical injury very close to the
source. Side-scan sonar, which uses a more focused beam of sound, is the most
common survey technique used in the siting of offshore wind facilities.
Side-scan sonar was found to result in only temporary behavior changes, even
during the more extreme cases, and is unlikely to result in any hearing
impairment or physical injury (MMS 2007a; NMFS 2002a). It is possible that
individual animals will leave the area or change behavior temporarily as a
result of the noise disturbance (MMS 2007a). In particular, behavioral
reactions of whales (cetaceans) may include: avoidance or flight from the sound
source, disruption of feeding behavior, interruption of vocal activity, or
modifications of vocal patterns. However, the response of an individual
cetacean may be unpredictable, as it depends on the animal's current activity,
its ability to move away quickly (especially a concern with regard to North
Atlantic Right whales), and the animal's previous experience around vessels
(MMS 2009a). It is unknown what long-term effects these changes in behavior may
have on the individual animal or entire cetacean populations.
7. Seals (pinnipeds) have shown avoidance in
response to noise generated by geophysical surveys (NMFS 2002b; Thomson
et al. 2001; MMS 2003; OSPAR 2009a). Since harbor seals
regularly haul-out on sites around Block Island (Kenney and Vigness-Raposa
2009), survey activities in these areas may cause a temporary disturbance. The
PEIS states that any displacement from the study area as a result of these
surveys is likely to be temporary, resulting in negligible impacts to marine
mammals (MMS 2007a; MMS 2009a). Siting facilities away from important marine
mammal congregation, mating or feeding areas and taking into account marine
mammal activity in the area when scheduling surveys will further minimize any
potential negative impacts (MMS 2007a).
8. Underwater noise from the construction of
an offshore renewable energy facility is generated during the installation of
the foundation piles used to support the turbines and transformer platforms.
Most offshore turbines are placed on steel foundations, which are affixed to
piles driven into the seabed. Piles can range in diameter from 1 to 5 m [
3.3-16.4 ft], with the larger piles being used for monopile turbines and
smaller piles used for jacketed structures. The piles are driven into the
bottom by powerful hydraulic hammers, causing very loud noise emissions, which
may be audible for marine mammals over distances of several tens of kilometers
(Thomsen et al. 2006; Nedwell et al. 2007).
The zone of audibility may extend beyond 80 km [49.7 mi] to perhaps hundreds of
kilometers for some marine mammal species (e.g. harbor porpoises and harbor
seals) (Thomsen et al. 2006). Yet pile driving for one single
turbine is of relatively short duration. The level of noise emitted by pile
driving operations is dependent on a variety of factors such as pile
dimensions, seabed characteristics, water depth, and the strength and duration
of the hammer's impact on the pile (Nedwell et al. 2007; OSPAR
2009a).
9. Research conducted by
Miller et al. (2010) modeled the extent of pile-driving noise within the Ocean
SAMP area and mapped the areas subject to sound intensities of concern under
the MMPA (see Table 8.18 in §8.4.5(H)(5)(a) of this Part and Figure 8.46
in §8.4.5(H)(9)(a) of this Part). This analysis was calculated for a 1.7 m
[5.5 foot] diameter pile (similar to those used in lattice jacket structures)
driven into the bottom with an impact hammer. The red shaded area represents
the zone of injury, the orange area represents the zone of harassment or
potential behavior response, and the yellow area represents the zone of
audibility or detection by marine mammals. It should be noted that this is an
estimate and that the zones may be larger or smaller depending on the actual
size of the pile and method of installation.
a. Figure 8.46: Estimate of the affected area
in the vicinity of pile driving (Miller et al. 2010).
10. Pile driving may create noise that may
adversely affect marine mammal feeding or social interactions, or alter or
interrupt vocal activity (MMS 2007; Thomsen et al. 2006).
However, these impacts will vary within, as well as between, species. Any
marine mammal that remains within the project area at the start of pile driving
activities are subject to the increased risk of hearing impairment that may
occur within close range (Madsen et al 2006; Thomsen
et al. 2006). Placing marine mammal observers onboard
construction vessels and halting construction activity once a marine mammal has
been spotted within a designated exclusion zone are precautionary measures that
can be taken to reduce this potential risk (MMS 2007a). In addition, acoustic
isolation of the ramming pile may reduce the noise level of pile driving
activities. Acoustic deterrent devices and ramp-up pile-driving procedures may
also help to protect individuals from impairment or injury by encouraging them
to leave the construction site (Thomsen et al. 2006; Tougaard
et al. 2003; Tougaard et al. 2005).
11. In Denmark, the construction of two
offshore wind farms, Nysted and Horns Rev 1, have provided opportunities for
monitoring the behavioral reactions of two marine mammal species, harbor
porpoises and harbor seals, to pile driving activities. Evidence of temporary
avoidance behavior during pile-driving at Horns Rev was found in harbor
porpoises up to approximately 20 km [12.4 mi] away, both visually, through
fewer observed individuals, and acoustically, through temporarily decreased
acoustic activity (Tougaard et al. 2003). This reduction in
echolocation clicks suggests that either pile-driving affected the porpoises'
behavior causing individuals to go silent, or the porpoises left the area
during this activity. Tougaard et al. (2003) observed a return
to previous acoustic activity after 3-4 hours. At the Nysted site, where piling
only occurred for a brief period of time, harbor porpoises left the area during
construction and stayed away for several days (Tougaard et al.
2005). Overall lower abundance of harbor porpoises was observed at the Nysted
site after construction when compared to baseline data, lasting at least until
the second year of operation (Tougaard et al. 2005). However,
it should be noted that researchers are uncertain if the observed long-term
avoidance of the Nysted site by harbor porpoises was caused by the noise
effects of construction. Porpoise abundance was relatively low in the area
before the start of construction, so the decrease in abundance may have been
unrelated to installation activities (Thomsen et al. 2006).
Edren et al. (2004) found a 10 - 60% decrease in the number of hauled out
harbor seals on a sandbank 10 km [6.2 mi] away from the Nysted construction
site during days of ramming activity. This effect was of short duration but
does suggest that both harbor porpoises and seals demonstrate behavioral
changes or avoidance during pile-driving activity, and that these effects can
span large distances.
12. In
addition to surveying and pile-driving activities, noise associated with ships
engaged in construction, operations and maintenance activities may potentially
impact marine mammals in the project area (Köller et al.
2006; OSPAR 2009a) (see Table 8.17 in § 8.4.5(H)(3)(a) of this Part).
Overall, the ambient noise created by marine transportation, including ships
associated with the wind farms as well as other ship traffic in the area, will
be of a higher intensity than what would likely be created by wind turbines
(OSPAR 2009a). Shipping noise should be taken into account when considering the
overall levels of ambient noise underwater where wind turbines are in place.
The use of ships in servicing the turbines and other activities should be
accounted for when predicting the overall noise levels from the wind farms
(Wahlberg and Westerberg 2005). Shipping noise is likely to be significantly
higher during the construction phase (BMT Cordah Limited 2003). It is estimated
that each turbine will require one to two days of maintenance each year;
depending on the size of a wind farm, ship noise could be present in the
vicinity of the turbines often (Thomsen et al. 2006). However,
given the existing levels of shipping in the Ocean SAMP area and resulting
background noise (see Chapter 7, Marine Transportation, Navigation and
Infrastructure) the added noise from maintenance vessels is likely to be
negligible. Observed reactions of marine mammals to vessel noise have included
apparent indifference, attraction (e.g. dolphins' attraction to moving
vessels), cessation of vocalizations or feeding activity, and vessel avoidance
(Richardson et al 1995; Nowacek and Wells 2001). Noise may also be caused by
transit of helicopters used to support offshore renewable energy facilities far
offshore (MMS 2007a). Marine mammal behavior would likely return to normal
following the passage of the vessel (Richardson et al. 1995).
Edren et al. (2004) conducted video monitoring during the
construction of the Nysted offshore wind farm and found no discernible changes
in harbor seal behavior as a result of the increased ship traffic, although
ship movements were controlled to avoid the seal sanctuary. In the Ocean SAMP
area, the most heavily used seal haul out site on Block Island is located
within a protected cove (see Figure 8.43 in § 8.4.5(E)(1) of this Part)
and therefore would not be affected by the noise from construction traffic.
However, the other haul out sites surrounding Block Island may be affected if
vessel routes pass in their vicinity or during winter seasons when these sites
are most frequently used (Kenney and Vigness-Raposa 2009). Prior to
construction, all potential impacts (including noise impacts) to marine mammals
by a proposed offshore renewable energy facility in the Ocean SAMP area will be
reviewed under the MMPA to determine if incidental take or harassment
authorization, or specific mitigation measures are required.
13. Underwater noise may also result from
cable laying activities, including cable laying vessels or jet plowing
techniques (OSPAR 2009b). Noise measurements are not available for cable laying
activities in Europe associated with offshore wind energy facilities (OSPAR
2009b). However, research conducted to assess the potential noise impacts
associated with the laying of submarine cables for the Cape Wind Energy Project
found that the jet plowing embedment process would not add appreciable sound
into the water column (MMS 2009a). However, the nature of the seabed will
dictate the type of cable installation procedures used, and thus the noise
profiles that will result will depend on the physical characteristics of the
seafloor (MMS 2007a). In areas with unconsolidated sediments, only the sound
associated with the cable laying vessels will likely be produced, as the
sediments insulate the cable laying noise (MMS 2009a).
14. Operational noise generated from offshore
renewable energy structures, such as by the spinning offshore wind turbines,
may be transmitted into the water column via the turbine support structures
(OSPAR 2006). The level of noise emitted into the water column by an
operational turbine varies based on wind speed, the speed of the spinning
blades, and the type of foundation structure (Wahlberg and Westerberg 2005;
Ingemansson AB 2003). The operational noise produced by wind turbines is
significantly less than the levels of noise produced during the construction
phase. Underwater noise generated by the turbines is mostly the result of the
movement of mechanical components within the generator and gearbox, which
result in vibrations in the tower, rather than sounds from the turbine blades
themselves. Both the frequency and intensity of sound generated by the turbines
increases with wind speed. To date, the available data on the effects of noise
from operating wind turbines are sparse, but suggest that behavioral effects,
if any, are likely to be minor and to occur close to the turbines (review by
Madsen et al. 2006; Nedwell et al. 2007). For
example, Koschinski et al. (2003) reported behavioral
responses in harbor porpoises and harbor seals to playbacks of simulated
offshore turbine sounds at ranges of 60-200 m [196.8-656.2 ft], suggesting that
the impact zone for these species is relatively small. In addition, because
noise emissions from operating wind turbines are of low frequencies and low
intensity (Nedwell et al. 2007), operational noise is not
thought to be audible to many marine mammal species over distances greater than
a few tens of meters, as the hearing abilities of most marine mammals are
better at higher frequencies (Richardson et al. 1995; Southall
et al. 2007). One exception may be baleen whales, such as the
North Atlantic Right whale, whose hearing abilities are thought to include very
low frequency sounds (Madsen et. al. 2006). Scientists predict
that individuals of this species may respond to noise from operating turbines
at ranges up to a few kilometers in quiet habitat (Madsen et
al. 2006). However, no studies have been performed to date on the
effect of noise from operational offshore wind turbines on right whales, or
baleen whales in general, and these predictions have been based primarily on
the results of related acoustic studies (Nowacek et al. 2004;
Richardson et al. 1995; Madsen et al.
2006).
15. Recent measurements by
Nedwell et al. (2007) at five operational wind farms off the
U.K. indicate that wind farm sound could not be detected at a hydrophone at
distances of a few kilometers outside the wind farm. Measurements taken at a
range of 110 meters from a 1.5 MW monopile GE turbine in Utgruden, Sweden in
water depths of approximately 10 meters found operational noise measured 118 dB
re 1 mPa2 in any 1/3 octave band at a range of 100 meters at full power
production (Betke et al. 2004). Based on these measurements
and measurements of the ambient noise in the waters just southwest of Block
Island, Miller et al. (2010) determined that the additional
noise from an operational offshore wind turbine is significantly less than
noise from shipping, wind and rain in the region. Miller et
al. (2010) calculated that the noise would be greater than the ambient
noise present within 1 km of the wind turbines and at ranges of 10 km
operational noise would be below the ambient noise in the region.
16. The decommissioning of offshore renewable
installations will also temporarily generate underwater noise. However, because
an offshore renewable energy facility has not yet been decommissioned, the
activities and duration of the removal is not yet known (Nedwell and Howell
2004). Abrasive jet cutting (using the force of highly pressurized water) is
likely to be used to cut piles from the seafloor, while the destruction of the
concrete foundations and scour protection may require some blasting or the use
of pneumatic hammers, if the protective structures cannot be lifted from the
seafloor after dismounting the turbine support structure. Currently, no sound
measurements are available on the use of abrasive jet cutting when
decommissioning offshore structures. While explosives may be a loud point
source of underwater sound, and consequently pose a serious risk of physical
damage to any marine mammals in the detonation area (MMS 2007a), non-explosive
removal techniques are expected to cause short-term, negligible to minor
impacts (MMS 2007a). Therefore, the PEIS suggests the use of these alternative
methods to minimize any adverse effects (MMS 2007a). If explosives are used,
following BOEM guidelines (NTL No. 2004-G06) may reduce the potential for
negative impacts (MMS 2007a).
17.
In summary, noise impacts associated with offshore renewable energy facilities
are currently thought to affect marine mammals. The nature and scale of effects
will depend on: the hearing ability of the species and the individual animal;
the distance the individual is from the sound source; the frequency and
intensity of the noise source; the activities of the marine mammals at the time
of noise exposure; the duration of the noise-producing activity (i.e. hours,
days, months); and transmission through the area (dependent upon physical
conditions of the area such as topography, geology, sea state, etc.). To date,
only a limited number of studies have been published documenting effects of
construction and operation of offshore wind energy facilities on two species of
marine mammals, harbor porpoises and harbor seals (Carstensen et
al. 2006; Tougaard et al. 2006; Koschinski et al.
2003). Additional studies have inferred potential effects based on theoretical
models or findings from similar activities in other industries (the most
comprehensive review of observed effects can be found in OSPAR 2009a). It
should be noted, however, that the range of effects may vary between
installations.
I. Vessel
Strikes (formerly § 850.5.2)
1.
Increased vessel traffic associated with the construction, operation, or
decommissioning of an offshore renewable energy facility may increase the risk
of ship strikes. Impacts are expected to be minor for most species, especially
seals and smaller cetaceans that are agile enough to avoid collisions (MMS
2007a). Of all the whale species present within the Ocean SAMP area, the
species considered at the greatest risk of vessel strikes are fin whales,
humpback whales, North Atlantic right whales and sperm whales, based on the
findings of the Large Whale Ship Strike Database (Jensen and Silber 2004; MMS
2007a). However, the response of an individual animal to an approaching vessel
may be unpredictable, as it depends on the animal's behavior at the time, as
well as its previous experience around vessels (MMS 2009a).
2. Of all whale species within the Ocean SAMP
area, the population-level impacts of a vessel strike would be most severe to
the North Atlantic right whale (MMS 2007a). Ship strikes more commonly result
in whale fatalities when a ship is travelling at speeds of 14 knots [16 mph] or
more. In fact, the number of ship strikes recorded decreases significantly for
vessels travelling less than 10 knots [11.5mph] (Jensen and Silber 2004), which
suggests that reducing ship speeds to this level may reduce the risk of vessel
strikes even further (NOAA National Marine Fisheries Service 2008). As a result
of this finding, the PEIS suggests vessels reduce ship speed and maintain a
safe operating distance when a marine mammal is observed (MMS 2007a; MMS
2009a). In addition, by locating offshore renewable energy installations away
from migratory routes, the risk of vessel strikes is further minimized (MMS
2007a). It should also be noted that there is already a vessel speed
restriction in place during parts of the Ocean SAMP area during certain times
of the year to minimize the risk of right whale ship strikes; this speed
restriction is part of the Right Whale Seasonal Management Area and is enforced
by NMFS (NOAA National Marine Fisheries Service n.d.). See Chapter 7, Marine
Transportation, Navigation, and Infrastructure for further
discussion.
J. Turbidity
& Sediment Resuspension (formerly § 850.5.3)
1. Water quality within a project area may be
affected by the construction and decommissioning activities, including cable
laying, associated with an offshore renewable energy facility. Specifically,
construction or decommissioning activities may re-suspend bottom sediments,
which may in turn increase concentrations of total suspended solids (TSS) in
the water column (MMS 2009a; OSPAR 2008). The level of impact caused by
increased TSS is primarily dependent upon the sediment composition of the
project site, grain size distributions, and the hydrodynamic regime (OSPAR
2006). Areas composed of fine grained, loose sediment, accustomed to frequent
increases in turbidity (associated with storms, tidal or wave action) will
likely not be substantially impacted by the temporary disturbances caused by
these activities (MMS 2009a). Increased TSS concentrations may impact prey
abundance in an area (i.e. zooplankton or fish species), and therefore
indirectly impact marine mammals which depend on those species as a food source
(MMS 2009a; Köeller et al. 2006). However, because
individuals can move to adjoining areas not affected by the temporary increases
in TSS, these impacts are not expected to pose a threat to marine mammals (MMS
2009a). In the case of the Cape Wind Project, while TSS concentrations were
anticipated around construction and decommissioning time periods, the increases
were predicted to be temporary and localized (MMS 2009a). Pre-construction
modeling may be useful in predicting the importance of sediment resuspension at
a particular site, and monitoring programs during the construction can be used
to validate model predictions of the potential TSS effects (OSPAR 2006).
Monitoring programs may help to ensure that TSS levels remain within an
acceptable range (OSPAR 2006).
2.
The PEIS also identifies the potential risk posed by re-suspending contaminated
sediments into the water column (MMS 2007a). The suspension of contaminated
sediments from construction activities may in some instances result in
bioaccumulation of toxins in marine mammal tissue, due to the consumption of
contaminated prey (MMS 2009a; see also Hooker et al.
2008)
3. Water quality around an
offshore renewable energy facility may potentially be impacted if illegal
dumping or accidental spills occurs from vessels or equipment. Vessel
discharges and oil spills are already subject to standard operating procedures
and discharge regulations (30 C.F.R. §
250.300 and
MARPOL, Annex V, Public Law 100-220 [101 Statute 1458]), and the discharge of
any legally discharged waste is not expected to pose any threat to marine
mammals (MMS 2007a). Substances that are legally discharged from vessels
offshore are rapidly diluted and dispersed posing negligible risk to marine
mammals (MMS 2007a). Accidental spills from offshore renewable energy
facilities may pose a potential hazard to marine mammals if they result in the
release of large volumes of hazardous materials (MMS 2007a). For example,
transformers, used to transmit energy generated from the offshore renewable
energy facilities to shore, may contain reservoirs of electrical insulating oil
or other fluids. The accidental release of these materials may impact the
health and survival of marine mammals exposed to the spill, or may indirectly
impact marine mammals by adversely affecting prey species in the area (MMS
2009a). The severity of these impacts depend on the location of the facility,
the volume and timing of the spill, the toxicity of the material and the
species exposed to the spill (MMS 2007a; MMS 2009a). An assessment performed on
the Cape Wind Project found that the potential risk associated with accidental
spills is insignificant to minor (MMS 2009a), and that precautionary measures
such as producing an oil spill response plan may minimize any adverse impacts
on marine mammals (NOAA 2009).
K. Electromagnetic Fields (EMF) (formerly
§ 850.5.4)
1. Cetaceans have received
attention with respect to induced magnetic fields around underwater
transmission cables as it is hypothesized that they use the Earth's magnetic
field to navigate during migration (Gill et al. 2005).
However, there is very little data supporting the theory of magnetic
orientation in cetaceans. If an effect does exist, transient mammals would
likely only be temporarily affected by an induced magnetic field (Gill 2005).
Moreover, since migration generally occurs in open water and away from the
seabed (Kenney and Vigness-Raposa 2009), electromagnetic fields are unlikely to
have a detrimental effect on whale migration (Gill et al.
2005). Research conducted by Miller et al. (2010) examined the
potential electromagnetic fields that may be created from submarine cables used
to support offshore renewable energy development in the Ocean SAMP area and
found that the effects of EMF will be confined to within 20 meters [65.6 feet]
of the cable. No adverse impacts to marine mammal behavior or navigation is
expected from the undersea transmission cables (MMS 2009a; Gill 2005). EMF
associated with offshore wind energy projects may have potential effects on
some fisheries resources; see § 8.4.7 of this Part
below.
L. Habitat
alteration & reef effects (formerly §850.5.5)
1. Offshore renewable energy installations
sited in soft sediment might locally change the sea bed characteristics from
soft, mobile sediments to a harder substrate by introducing hard structures for
scour protection (rock, concrete mattresses, grout bags etc. Underwater
structures are soon overgrown by sessile, benthic animals and algae which may
increase the biomass locally, and attract fish and marine mammals as their
predators (Wilhelmsson et al. 2006; OSPAR 2006; NOAA 2009).
Similarly, the steel piles introduce a hard substrate into the water column,
and provide a surface that can be colonized by species that might not
ordinarily be present in soft sediment environments (OSPAR 2006). The offshore
wind farm foundations at Horns Rev and Nysted have been readily colonized with
epifouling communities, causing a local increase in biodiversity compared to
amounts recorded prior to construction (DONG Energy et al.
2006; Bioconsult A/S 2003; Energi E2 A/S 2004). However, no evidence has been
found to date to suggest that these reef effects enhance or alter the prey
availability of marine mammal species in the area. For a more detailed
discussion of this potential effect see §8.4.3 of this
Part.
8.4.6 Sea Turtles (formerly § 850.6)
A. The observed effects of offshore renewable
energy development on sea turtles are unknown, as sea turtles are not present
in any of the areas where wind turbines are currently in place (MMS 2007a).
According to Kenney and Vigness-Raposa (2009), the sea turtles that may be
found in the Ocean SAMP area include the following:
1. Table 8.19. Abundance and conservation
status of Ocean SAMP area sea turtles (Kenney and Vigness-Raposa 2009)
|
Turtle |
Status |
Abundance |
|
Leatherback Sea Turtle (Dermochelys coriacea) |
Endangered |
The sea turtle most likely to be found in Ocean SAMP area, found in Ocean SAMP area in summer and early fall when water is warmest. Dispersed; higher abundance outside Ocean SAMP area. |
|
Loggerhead Sea Turtle (Caretta caretta) |
Threatened |
More abundant in the Northeast than Leatherbacks, but less likely to be found in the Ocean SAMP area - not often seen in cool or nearshore waters. May be seen occasionally in summer or fall. |
|
Kemp's Ridley Sea Turtle (Lepidochelys kempii) |
Endangered |
Small juveniles known to use habitats around Long Island and Cape Cod, and may pass through Ocean SAMP area but are not detected in surveys. |
|
Green Sea Turtle (Chelonia mydas) |
Threatened |
Small juveniles known to use habitats around Long Island and Cape Cod, and may pass through Ocean SAMP area but are not detected in surveys. |
2.
Sea turtles may use the Ocean SAMP area for foraging. They are capable of
diving to great depths, although a study of sea turtles off Long Island found
them primarily foraging in waters between 16 and 49 feet (4.9 and 14.9 meters)
in depth. Leatherback turtles, likely the most abundant sea turtles in the
Ocean SAMP area, have been shown to dive to great depths and may spend
considerable time on the bottom, sometimes holding their breath for as long as
several hours. Some sea turtles, particularly green sea turtles, feed on
submerged aquatic vegetation (NOAA National Marine Fisheries Service 2009).
While the placement of wind turbines will be at depths greater than where this
foraging takes place, if cables are placed through areas of submerged aquatic
vegetation, this could have an effect on sea turtles. Similarly, many sea
turtles may feed on benthic invertebrates such as sponges, bivalves, or
crustaceans, all of which are likely be found in the Ocean SAMP area (NOAA
National Marine Fisheries Service 2009). Sea turtles may be affected by any
loss of these food species during the cable-laying process; again, turtles are
unlikely to forage at the depths where the turbine bases are likely to be
located. Leatherback turtles are known to consume Lion's mane jellyfish
(Cyanea capillata) as a mainstay of their diet; these
jellyfish are plentiful in the Ocean SAMP area during the summer and fall
(Lazell 1980).
3. Additionally, any
of these turtle species may migrate through the Ocean SAMP area as part of
their northward or southward migration in spring and fall, respectively (NOAA
National Marine Fisheries Service 2009). While sightings of most of these
species are infrequent, sea turtles, particularly juveniles, are not routinely
detected during surveys, meaning they may be more common in the Ocean SAMP area
than survey data would suggest. All of the species of sea turtles noted in the
table are likely to be present in the Ocean SAMP area from late spring/early
summer through late fall.
B. Noise (formerly § 850.6.1)
1. Little is known about the hearing
capabilities of sea turtles. Existing data estimate the hearing bandwidth of
the four species of turtles found within the Ocean SAMP area at between 50 and
1,000 Hz, with a maximum sensitivity around 200 Hz. They are thought to have
very high hearing thresholds, at around 130 dB re 1 µPa (MMS 2009a). It
is believed that pile driving and vessel noises are within the range of hearing
of turtles, although they may have a limited capacity to detect sound
underwater. Observed reactions from sea turtles exposed to high intensity
sounds include startle responses such as head retraction and swimming towards
the surface, as well as avoidance behavior (MMS 2007a). For more detailed
information on the effects of noise within the SAMP area, see §8.4.5(H) of
this Part, Effects of Noise on Marine Mammals.
2. The Cape Wind FEIS (MMS 2009a) predicts
that no injury during the pile driving process is likely to occur to sea
turtles, even if the turtle were as close as 30 m (98.4 feet) from the source.
This prediction is based on noise estimates created assuming the use of
monopiles, and based on the particular sound characteristics of the proposed
location for the Cape Wind project; estimates for the Ocean SAMP area would
differ. The noise generated by pile driving is likely to cause avoidance
behavior in sea turtles, which may move to other areas. Sea turtles migrating
through the area may also be affected, as they may avoid the construction area.
The Cape Wind FEIS predicted these effects to be short-term and minor (MMS
2009a). The noise created during construction, and thus the effects of noise on
sea turtles, may vary depending on the size of the piles and the
characteristics of the particular site.
3. Any seismic surveys used in the siting
process have the potential to affect individual sea turtles by exposing them to
levels of sound high enough to cause disturbance if a turtle is within a
certain distance of the sound source (1.5 km [0.9 miles]). While the Cape Wind
EIS predicted only minimal effects to sea turtles from seismic surveys (MMS
2009a), the effects to sea turtles from seismic surveys in the Ocean SAMP area
will depend on the type of survey device used, the water depths, and other
factors.
4. The Cape Wind EIS
predicted that levels of noise generated by construction and maintenance
vessels are expected to be below the levels that would cause any behavioral
reaction in sea turtles except at very short distances. Likewise, the Cape Wind
EIS predicted that sound generated by wind turbines during operation is not
expected to affect the behavior or abundance of sea turtles in the area (MMS
2009a).
5. The levels of sound
generated by the turbines during operation could have the ability to interfere
with communication, the location of prey or the orientation of sea turtles if
the sounds are in the same frequency ranges heard by sea turtles. As it is not
well understood what the hearing capacity of sea turtles is, more studies would
be needed to understand whether the sound generated by wind turbines would have
any effect (MMS 2007a).
C. Habitat disturbance (formerly §
850.6.2)
1. Cable-laying activities may cause
sea turtles to temporarily change swimming direction, and may disturb sea
turtles as they typically like to rest on the bottom. The increased turbidity
as a result of cable-laying and construction, however, may interfere with the
ability of sea turtles to forage by obscuring or dispersing prey (MMS
2009a).
2. Sea turtles could be
harmed by marine debris generated from the personnel working on the
construction, operation, or decommissioning stages, particularly plastics that
may be accidentally or purposely discarded, which may be mistaken for prey
items by turtles, or which may cause them to become entangled (MMS 2009a). The
dumping of marine debris and other waste is already strictly regulated under
existing statutes (30 C.F.R.
§
250.300 and MARPOL, Annex V, Public
Law 100-220 [101 Statute 1458]), and if followed marine debris will likely not
pose a great threat to sea turtles.
3. Sea turtles may be at increased risk of
ship strike from increased vessel traffic in the Ocean SAMP area, particularly
during construction activities. However, ship strikes are relatively rare, and
increased vessel traffic will not necessarily lead to an increase in ship
strikes. Vessels engaged in construction activities are probably moving too
slowly to present a risk, as turtles can easily move to avoid them. Collision
risks will be greater with vessels moving to and from the construction site
(MMS 2009a). Sea turtles may avoid areas of high vessel activity, or may dive
when approached by a vessel (MMS 2007a). Turtles engaged in feeding are at less
of a risk for collision, as they spend most of their time submerged. Loggerhead
and Kemp's ridley turtles are bottom feeders, so spend most of their time well
below the surface, but leatherback turtles feed at or near the surface, and so
are at greater risk of collision (MMS 2009a).
4. Lights from construction activities during
non-daylight hours could affect sea turtle hatchlings, which are known to be
attracted to light (MMS 2007a). However, sea turtle hatchlings are not expected
to be found within the SAMP area, as sea turtles do not nest in this
area.
D. Electromagnetic
fields (formerly § 850.6.3)
1. Sea
turtles have been found to use the earth's geomagnetic field for orientation
and migration (MMS 2007a). However, the Cape Wind FEIS anticipated no adverse
impacts from electromagnetic fields on sea turtles (MMS 2009a). Electromagnetic
fields may have potential effects on some fisheries resources; see §
8.4.7(D) of this Part below for further information.
E. Reef effects (formerly § 850.6.4)
1. The potential reef effects of the
turbines, attracting finfish and benthic organisms to the structures, could
affect sea turtles by changing prey distribution or abundance in the Ocean SAMP
area. Sea turtles that eat benthic invertebrates, particularly loggerhead and
Kemp's ridley turtles, which consume crustaceans and mollusks, may be attracted
to the structures as an additional food source. Sea turtles may also be
attracted to wind turbine structures for shelter; loggerheads in particular
have been observed using oil rig platforms for this purpose (NRC 1996 in MMS
2009a). Loggerheads are the species most likely to be attracted to the wind
turbines for both food and shelter, and they are frequently observed around
wrecks and underwater structures (NRC 1996 in MMS 2009a). For more on reef
effects, see §8.4.3(D) of this Part, Reef Effects and Benthic
Ecology.
8.4.7 Fisheries Resources and Habitat (formerly § 850.7)
A. Offshore renewable energy development may
have several potential effects on fisheries resources and habitat. Generally,
the effects of offshore renewable energy projects on fisheries resources are
difficult to interpret given the lack of scientific knowledge and consensus in
several relevant subject areas. Given the information available, potential
effects to fisheries resources and habitat are discussed below in general
terms, but it is important to note that site-specific impacts of an offshore
renewable energy project in the Ocean SAMP area will require separate, in-depth
evaluation as part of the permitting process. It also must be noted that if
threatened or endangered species are found in the project area, additional
consultation with relevant federal agencies in accordance with the Endangered
Species Act would be necessary to evaluate any potential impacts to these
species (MMS 2007a). For areas where Essential Fish Habitat has been
designated, the Magnuson-Stevens Fishery Conservation and Management Act
requires federal agencies to consult with the National Marine Fisheries Service
(MMS 2007a). See Chapter 5, Commercial and Recreational Fisheries for more
information on endangered or threatened fish species and on Essential Fish
Habitat. See also Chapter 10, Existing Statutes, Regulations and Policies for
more information on the ESA as well as the Magnuson-Stevens Fishery
Conservation and Management Act.
B.
With regard to fisheries resources, potential effects may take place at any
phase of the project, including pre-construction testing and site
characterization, construction, operation, and decommissioning. Some of these
effects may include, but are not limited to: underwater sound associated with
increased vessel traffic, scientific surveys, construction, operation, and
decommissioning; electromagnetic fields created by the cables connecting the
turbines and carrying the electricity to land; construction-related habitat
disturbance; water quality impacts; changes in benthic community composition;
other effects of structures, including the reef effect; and the effects of
decommissioning offshore renewable energy developments.
C. Underwater sound (formerly § 850.7.1)
1. As noted above in § 8.4.5(H) of this
Part, an offshore renewable energy project would generate underwater sound in
all phases of development. Noise generated by pile driving activities during
construction may be most significant and potentially harmful to fish
individuals and then onto populations. For more detailed information on sound
produced in the construction and operation of an offshore wind facility, please
see § 8.4.5(H) of this Part, Effects of Noise on Marine Mammals.
2. Fish vary greatly in their hearing
structures and auditory capabilities, so it is difficult to generalize about
the effects of noise generated by wind farm construction and operation on fish.
There is lack of knowledge about the hearing capacities of most fish species.
Certain fish species are thought to be hearing specialists, and may have
enhanced hearing sensitivity and bandwidth, while others may be hearing
generalists, and may be less sensitive to sound (Popper and Hastings 2009).
Similar to marine mammals, the effect of noise will depend on the overlap
between the frequency of the noise and the level of hearing of the species, and
whether the sound exceeds the level of ambient noise (Thomsen et
al. 2006). The impact of the sound produced will also vary greatly
depending upon the environmental setting and conditions at the time and place
where the sound is being produced (Popper et al.
2006).
3. The potential effects of
sound from wind farm surveying, construction, decommissioning, and operation,
on fish can be divided into three general categories:
a. temporary or permanent hearing damage or
other physical injury or mortality;
b. behavioral responses; for example, the
triggering of alarm reactions, causing fish to flee or interrupting activities
necessary for survival (e.g. feeding) and reproduction, and potentially
inducing stress in the fish;
c.
masking acoustic signals, which may be communication among individuals, or may
be information about predators or prey (Thomsen et al.
2006).
4. As noted in
8.4.5(H) of this Part, activities in the pre-construction phase generating
underwater noise may include side-scan sonar and air guns used in seismic
surveying. Studies on fish exposed to air gun blasts have found damage to
sensory cells in the ear. While air guns are not likely to be used in the
construction or operation of wind farms, they may be used in pre-construction
seismic surveys for determining geological hazards and soil conditions in
siting a wind farm (MMS 2007a). Side-scan sonar is likely to have little impact
on fish, as it is unlikely to cause hearing impairment or physical injury (MMS
2007a).
5. The construction phase
is most likely to produce levels of sound that could generate temporary and
permanent hearing loss for fish near the source. Injuries of tissues or
auditory organs can also occur at close range. Pile driving creates an
impulsive sound when the driving hammer strikes the pile, resulting in a rapid
release of energy (Hastings and Popper 2005). Peak sound levels produced by
pile driving have been measured at anywhere from 228 dB re-1 µPa to 257
dB re-1 µPa, at frequency levels ranging from 20 to more than 20,000 Hz;
peak sound levels will vary depending on pile size, material, and equipment
used (see Table 8.17 in § 8.4.5(H)(3)(a) of this Part). Only a handful of
studies have been conducted on fish in the vicinity of pile driving, and while
some have found evidence of injury or mortality in the fish near the source of
the sound, others have found no mortality or injury. One study of pile driving
found fish of several different species were killed within at least 50 m [164
feet] of the pile driving activity; it also found an increase in the number of
gulls in the area, indicating additional fish mortality (Caltrans 2001).
Another study found that the noise levels produced by pile driving during wind
tower construction and cable-laying could damage the hearing of species within
100m [328 feet] of the source (Nedwell et al. 2003).
6. Impacts to fish from sound can be in the
form of damage to organs such as the swim bladder, or damage to the auditory
sensor in the ears. Sound can also cause permanent or temporary threshold shift
in hearing (PTS or TTS respectively), meaning fish lose all or part of their
hearing, on either a permanent or temporary basis. There is some evidence that
fish, unlike mammals, can repair their sensory cells used for hearing, and may
recover from hearing loss caused by underwater noise. Popper et
al. (2005) found the effects from even substantial TTS to have worn
off for fish within eighteen hours of exposure. However, hearing loss, even if
temporary, could render the fish unable to respond to environmental sounds that
indicate the presence of predators or that allow the location of prey or
potential mates (Popper and Hastings 2009).
7. A review and modeling study conducted by
Thomsen et al. (2006) based on measurements of wind turbines
in the German Bight and Sweden found that sound levels created during pile
driving for construction of wind turbines was loud enough to be heard at long
distances by some fish species - perhaps as far as 80 km [49.7 mi] from the
source for cod and herring, which are considered to be sensitive to sound.
Salmon and dab, which have a poor sensitivity for sound pressure, could in
theory detect pile driving sound over large distances as well. Flatfish might
detect sound that is partly transported through the sediment. Pile driving
noise may have the effect of masking other biological noises out to this
distance. The nature and scale of behavioral response cannot be determined;
however, behavioral responses to the construction noise might happen anywhere
within the zone of audibility and could affect fish reproduction and population
levels if biologically important activities such as migration, feeding, and
spawning are interrupted. The authors determined that injury and mortality may
occur in the vicinity of the activity (Thomsen et al. 2006).
One playback study of pile driving sounds at relatively low pressure levels
found sole to increase their swimming speeds during the playback, while cod
were found to freeze their movements at the start of the playback
(Mueller-Blenkle et al. 2010). While studies have generally
found that impacts on fish will decrease the further from the source of the
sound, this effect is not clearly understood because the relationship between
distance and sound level is not straightforward. In some cases sound levels may
be higher at some distances from the source due to propagation through the
seabed and sound reflections from objects (Hastings and Popper 2005).
8. The relationship between sound exposure
and physiological damage with regard to fish is not well understood, and more
research is required to determine the potential effects of pile driving on fish
(Thomsen et al. 2006). Little is known about potential
long-term effects, including later death from injury, predation, or behavioral
changes that may affect the individual fish or their populations, nor have
studies examined the potential cumulative impacts from pile driving. The
effects that noise may have on eggs and larvae have been little studied.
Research is also lacking on the impacts on fish at larger distances from the
source, where they are unlikely to be killed but may suffer from other
physiological effects such as damage to the swim bladder or internal bleeding
(Hastings and Popper 2005).
9. The
noise created during the construction and decommissioning processes may cause
some fish species to leave the area. This could cause a disruption in feeding,
breeding, or other essential activities, and may have significant impacts if
fish are removed from a spawning area. Less mobile species are likely to be
more susceptible (Gill and Kimber 2005). The effect on fish populations would
be greater if they are dispersed during the times of year when they would be
naturally congregating for spawning or other purposes (Gill and Kimber 2005).
Thus, effects will be determined in part by the timing of the project, such as
the time of year when the noise disturbance occurs and for how long it occurs.
Some studies have found that fish displaced from an area by noise during
construction processes are likely to return following construction activity
(Hvidt et al. 2006 referenced in MMS 2007a). This may be
dependent upon duration of the construction project; if construction occurs
over a prolonged period, some fish species may not return. The length of time
will in turn be dictated by a number of factors including the number of
turbines, the availability of vessels, and access to the site as a result of
weather conditions. The cumulative effects are likely to be more significant
for a larger wind farm where more turbines would be constructed and the period
of construction is longer. Miller et al. (2010) predicted that pile driving
activity within the Ocean SAMP area could have observable behavioral effects on
fish within 4000 m (2.5 miles) of the pile driving activity. As described in
§8.4.5(H) of this Part, this analysis was calculated for a 1.7 m [5.5
foot] diameter pile (similar to those used in lattice jacket structures) driven
into the bottom with an impact hammer. If explosives were used in the
decommissioning process, the noise produced could have a serious impact on any
marine life within 500 m (0.3 miles) of the activity (Miller et
al. 2010) (see §8.4.5 of this Part for more
information).
10. Fish of different
species produce a variety of sounds, many of which may be used for mating or
other communication purposes. The sounds produced by wind turbines,
particularly in the construction phase, may mask some of these sounds produced
by fish, as the frequencies of pile driving and fish signals overlap. For
example, cod, which are found in the Ocean SAMP area, produce a number of
grunting sounds that are used in defensive and aggressive behaviors, and in
courting mates. Masking these sounds with construction noise could have
implications for mating and other behaviors. Because the transmission of the
sounds could be audible by some species over great distances, the masking
effects may also occur over great distances (Thomsen et al.
2006). The effect may depend on the signals produced by the fish; in species
where only a single sound makes up a communication signal the effect may be
negligible, because the duration of the pile driving sound is very short.
However, some fish produce sequences of sounds that might be disrupted by pile
driving pulses. Where a large number of turbines are being installed and the
length of construction is longer, the masking effect may be appreciable
(Thomsen et al. 2006). The noise produced in construction and
operation could also mask the sounds of approaching predators or prey.
Detecting those sounds may be crucial for survival (Wahlberg and Westerberg
2005). However, because neither the hearing capabilities of most fish nor the
function of sounds produced by the fish is well understood, the effects of
masking cannot yet be determined (Thomsen et al.
2006).
11. One potential effect on
fish from noise could be stress; while this is difficult to quantify, some
studies have shown that exposure to stressors can result in opportunistic
infections, or may make fish more susceptible to predation or other
environmental effects. Some studies on fish exposed to noise found no
significant change in stress levels, but these results cannot necessarily be
extrapolated to predicting the overall effects of exposure to noise on fish
stress levels (Popper and Hastings 2009).
12. If the effects of noise on fish are
poorly understood, the effects on invertebrates are even less well understood.
One study found that shrimp demonstrated decreases in growth and reproductive
rates when exposed to noise for an extended period (Popper and Hastings
2009).
13. Research on existing
offshore wind farms in the Baltic Sea has found that the operation of the
turbines adds to the existing array of underwater sound, and that the acoustic
disturbance caused by the turbines is most likely a function of the number of
turbines and their operation procedure (studies reviewed by Gill 2005). As
noted above, operational noise produced by wind turbines is significantly less
than the levels of noise produced during the construction phase. Even within
ten meters of the turbine, the noise created is not likely to be sufficient to
cause temporary or permanent hearing loss in any species of fish (Wahlberg and
Westerberg 2005). One study found that the noise created by a 1.5 MW turbine
was merged with ambient noise within one kilometer from the source (Thomsen
et al. 2006). Miller et al. (2010) predicted
that within the Ocean SAMP area where eight wind turbines are proposed south of
Block Island, the operational noise of the turbines would contribute 424 pW/m2
or 88 dB re 1 mPa of additional noise, significantly less than the noise
produced by shipping, wind, and rain in the area. This level would be greater
than ambient noise within one kilometer (0.6 miles) of the source, and would be
below ambient noise levels at a distance of ten kilometers (6 miles) from the
source (Miller et al. 2010). Underwater noise created by
offshore wind turbines in Europe has been measured at 118 dB re 1 mPa2 for a
1/3 octave band at a range of 100 meters during full power production (Betke
et al. 2004).
14.
Thomsen et al. (2006) predicted the noise generated by wind
turbine operation might be heard up to four or five kilometers from the source
by fish with exceptional hearing such as cod and herring, and maybe less than
one kilometer by fish with less specialized hearing capabilities such as dab
and salmon. Any behavioral or physiological effects on fish for levels of noise
created by turbine operation would likely be restricted to very short ranges
(Thomsen et al. 2006). However, it is important to note that
most of these studies have been for 1.5 MW turbines, while those proposed for
the Ocean SAMP area would likely be 3.6 or 5.0 MW. Additional studies are
needed on the noise levels generated by these larger turbines.
15. As noted above, another source of sound
from wind turbine projects is ship traffic, from ships carrying parts and
maintenance equipment during the construction, operation, and decommissioning
processes. The noise levels of sound created by vessels will not cause physical
harm to fish, but may cause avoidance of the area (MMS 2007a). The duration of
avoidance may be determined by the duration of construction activity and the
accompanying period of increased vessel traffic.
D. Electromagnetic fields (formerly §
850.7.2)
1. Producing electricity with a wind
turbine requires it to be moved over long distances by means of a submarine
cable. The transmission is either via high voltage Direct Current (DC) or
Alternating Current (AC) cables, with AC being the favored for short distances
and DC for longer distances between the project and shore. These cables will
necessarily produce magnetic fields around the cables. The intensity of the
magnetic field increases with the electric current, and decreases with distance
from the cable. The design of industry standard AC cables prevent electric
field emissions, but do not prevent magnetic field emissions. These magnetic
emissions induce localized electric fields in the marine environment as sea
water moves through them. Furthermore, in AC cables the magnetic fields
oscillate, and thereby also create an induced electric field in the environment
around the cables, regardless of whether the cable is buried. Thus the term
electromagnetic field, or EMF, refers to both of these created fields (Petersen
and Malm 2006).
2. Exposure to
magnetic fields is not unique to undersea cables; the earth has its own
geomagnetic field, which many organisms utilize for orientation. Little is
understood about the orientation of animals in response to the geomagnetic
field, but evidence of geomagnetic orientation has been observed in a number of
marine species, including fish, mollusks, and other crustaceans. In laboratory
experiments conducted on a number of different marine animals in response to
static magnetic fields generated by electrical current, most demonstrated no
short-term change in behavior when the magnetic field was introduced. In one
experiment by Bochert and Zettler (2004) where several organisms were exposed
to EMF generated by a DC power source, of four crustacean species, blue
mussels, and flounder studied, only one crustacean species, an isopod,
demonstrated any avoidance of the magnetic field. In other experiments by the
same authors on the long-term effects of magnetic fields on crustaceans and
flounder, no significant effects were demonstrated. The authors conclude that
the static magnetic fields of submarine cables produced by DC currents have no
clear influence on the orientation, physiology, or movement of the benthic
animals they tested (Bochert and Zettler 2004).
3. However, some evidence exists supporting
the argument that EMF may have detrimental effects. Other studies have shown
that some species of sharks, rays, and bony fishes detect electromagnetic
fields and have demonstrated sensitivity to these EMFs (Gill et
al. 2005). The induced electrical fields created by the magnetic
fields from the cables are within the range of electrical transmissions
detectable by sharks and rays (Gill and Kimber 2005). Exposure to certain
magnetic fields was found to delay the development of embryos in fish and sea
urchins (Cameron et al. 1985; Cameron et al. 1993; Zimmerman
et al. 1990). Barnacle larvae exposed to high frequency AC EMF were found to
retract their antennae, which would interfere with settlement (Leya et
al. 1999). In another study, brown shrimp (Crangon crangon) were found
to be attracted to magnetic fields of the magnitude that would be expected to
be present around wind farms (ICES 2003). Little is known about the effects of
EMF on lobsters. However, because effects have been demonstrated on brown
shrimp and other crustaceans, an effect on lobsters can be
anticipated.
4. Species using the
Earth's magnetic field for navigation or orientation may be affected by the
EMF, possibly becoming confused, but this effect will likely be short-lived as
the animal moves through the area. Species that are magnetosensitive may either
be attracted to or avoid the area (Gill 2005). If elasmobranchs (sharks, rays
or skates) and other fish are sensitive to the electromagnetic fields and avoid
passing over the cables, this could prevent movement from one location to
another, trapping fish either within our outside of the cables (BMT Cordah
Limited 2003). It is generally thought that the magnetic fields created by the
cables will be much lower than the earth's geomagnetic field and will therefore
cause no significant response (Gill and Kimber 2005). One study on the European
eel (Anguilla anguilla) found that eels significantly decrease
their swimming speed when passing over an AC cable (Westerberg and Lagenfelt
2008). A study of cables at Danish wind farms found some effects on fish
behavior from the presence of the cables, but the effects included both
avoidance and attraction, and could not be correlated with the strength of the
EMFs (DONG Energy et al. 2006). Catch studies on some species
of fish (Baltic herring, common eel, Atlantic cod and flounder) at the Nysted
wind farm in Denmark found the catches of these species were reduced in the
vicinity of the cables, indicating the migration of fish across the cables may
be reduced, but not blocked. In a separate study, they also found cod
accumulating close to the cables however this was not when the cables were
energized so there may be some other stimuli that the fish were responding to
such as the physical presence of the cable trench (DONG Energy and Vattenfall
2006).
5. If the electric fields
being emitted by the cables approximate the bioelectric fields of some species,
there is a possibility that certain electro-sensitive species, particularly
elasmobranchs (sharks, skates, and rays) and sturgeon species, will be
attracted to the cables, thinking them to be prey. The same species may be
repelled by stronger electric fields closer to the cables, depending on the
power sent through the cable and the characteristics of the cable itself.
Because the cables will be buried in sediment or laid along the bottom, benthic
species are most likely to encounter them (Gill and Kimber 2005). There is one
report of sharks biting an unburied cable on the seafloor that was emitting
induced AC electric fields (Marra 1989); however, there is little other data on
interactions between sharks or other species and cables.
6. Miller et al. (2010)
predict the electromagnetic fields that would be produced by the 26 kVA power
cables likely to be used for the wind turbines proposed south of Block Island
could have behavioral effects on marine life within 20 m (66 feet) of the
cables.
7. There is no conclusive
evidence at present on whether EMFs may have an impact on marine species
(Johnson et al. 2008). However, because the effects of
electromagnetic fields on fish and other species are poorly understood, more
research is needed in this field. The effects of EMFs on species present within
the Ocean SAMP area should not be assumed until further research is completed.
It is not known whether resident species will be able to habituate to EMF, but
this could be important for helping to determine appropriate mitigation
measures.
E. Habitat
disturbance (formerly § 850.7.3)
1.
Disturbance to existing habitat is likely to result through the construction of
offshore renewable energy infrastructure. Here, habitat disturbance is used
broadly to refer to sediment disturbance and settling; increased turbidity of
the waters in the construction area; and the installation of infrastructure
including piles, anti-scour devices, and other structures (MMS 2007a). The
period of time and the extent of the disturbance, and thus its severity, will
depend on the size of the wind farm and the amount of time necessary to
construct it. For the proposed large-scale project in the Ocean SAMP area, this
is likely to be a year or two. The total area of the seafloor affected will be
only a small percentage of the entire Ocean SAMP area; however, the overall
effect will depend in part upon the relative prevalence or scarcity of the
habitat type(s) affected, and the availability of similar habitat in the
adjacent area. For more on the effects of offshore renewable energy on habitat
and the benthic ecology of the Ocean SAMP area, see §8.4.3 of this
Part.
2. The construction of wind
turbines is likely to have both short- and long-term effects on habitat.
Habitat conversion and loss can result because of physical occupation of the
substrate, and includes both changes to existing habitat and the creation of
new habitat. Scour protection around the structures, which is made up of rock
or concrete mattresses, increases the loss or conversion of habitat (Johnson
et al. 2008). Direct effects to the seabed are likely to be
limited to within one or two hundred meters of the structure, and there are
likely to be areas between turbines which remain undisturbed (OSPAR 2006). For
more on the creation of new habitat, see §§ 8.4.7(I) (Reef Effects
and Fisheries) and 8.4.3(D) (Reef Effects and Benthic Ecology) of this
Part.
3. Construction of the wind
turbine foundations and the installation of cables can result in increased
turbidity in the water column as well. This may in turn affect primary
production of phytoplankton and the food chain, which could lead to an
increased likelihood of eutrophic conditions. However, these effects are likely
to be short-term and localized, and the overall impact on fish resources would
be negligible (MMS 2007a). Removal of sediments may result in habitat loss
(Gill 2005). These are generally short-term impacts which will subside once
construction has been completed (Johnson et al. 2008). Any
sediment resuspended in the construction or decommissioning processes are
likely to be transported by water movement, and may smother the neighboring
habitats of sedimentary species. These sediments may also carry contaminants
with them if the area has a history of industrial processes emitting into the
adjacent waters (Gill 2005).
4. The
interference in water flow caused by the wind turbine substructures may
accelerate local tidal currents and wave action around the structures, forming
scour holes in the sea bed adjacent to the pilings. These holes may be
attractive habitat to species such as crab and lobster, and to some fish
species (Rodmell and Johnson 2005).
5. Additional impacts from wind turbines
would come from the eventual decommissioning and removal of the undersea
structures, immediately reducing habitat heterogeneity and removing a large
component of the benthic community that has established since the wind farm has
been in operation (Gill 2005).
6.
The installation and burial of submarine cables causes temporary habitat
destruction through plowing and from barge anchor damage, and can cause
permanent habitat alteration if the top layers of sediment are replaced with
new material during the cable-laying process, or if the cables are not
sufficiently buried within the substrate. Likewise, cable repair or
decommissioning can impact benthic habitats. The effect of the cables will
depend on the grain size of sediments, hydrodynamics and turbidity of the area,
and on the species and habitats present where the cable is being laid (OSPAR
2008). Undersea cables can also cause damage if allowed to "sweep" along the
bottom while being placed in the correct location. The most serious threats are
to submerged aquatic vegetation, which serves as an important habitat for a
wide variety of marine species. Shellfish beds and hard-bottom habitats are
also especially at risk (Johnson et al. 2008).
7. The placement of wind turbines, especially
in large arrays, may affect flow regimes by altering tidal current patterns
around the structures, which may affect the distribution of eggs and larvae
(Johnson et al. 2008). Because the structures are likely to affect currents,
the settlement of new recruits may be locally affected. These effects on
habitat will be most harmful if they affect the spawning or nursery areas of
species whose populations are depleted, especially if the spawning or nursery
areas used by these species are limited and the species have long maturation
periods, such as sharks and skates (Gill 2005). A study of turbines in Danish
waters found little to no impact on native benthic communities and sediment
structure from a change in hydrodynamic regimes (DONG Energy et
al. 2006). For more on the effects of wind turbines on coastal
processes, see § 8.4.2 of this Part.
F. Water quality impacts (formerly §
850.7.4)
1. Offshore renewable energy
facilities would result in increased vessel traffic through the
pre-construction site characterization, construction, operation, and
decommissioning phases. The PEIS indicates that such an increase in traffic
could increase the likelihood of fuel spills as a result of vessel accidents or
mechanical problems, though it indicates that the likelihood of such spills is
relatively small because of the small amount of vessel traffic that would be
associated with the project (MMS 2007a). The risk of fuel spills could also
increase because of the increased likelihood of vessel collisions with the wind
turbine structures.
2. Wastewater,
trash, and other debris can be generated at offshore energy sites by human
activities associated with the facility (in construction and maintenance
processes). The platforms may hold hazardous materials such as fuel, oils,
greases, and coolants. The discharge of these contaminants into the water
column could affect the water quality around the facility. Large-scale offshore
renewable energy projects are likely to have one or more transformers, which
will contain dielectric fluid, such as mineral oil, which could pose a threat
to water quality through leakage or in the event of a collision (MMS 2009a).
Vessels traveling to and from the platforms may dump gray water or sewage, or
may release plastics and other debris (Johnson et al.
2008).
3. Water quality may also be
impacted during the construction process by re-suspending bottom sediments,
increasing the sedimentation within the water column. This may impact the
abundance of planktonic species, and could lead to
eutrophication.
G.
Changes in community composition (formerly § 850.7.5)
1. Wind energy and other offshore renewable
energy projects could have indirect ecological effects that could affect the
composition of fish species within the area. During the construction and
decommissioning phases of a project, highly mobile fauna, including fish and
large crustaceans, are likely to be displaced from the area, and there may be
changes to some habitats, either through habitat loss or through enhancement.
These factors may affect the composition of species found in the area. For more
on the effects of changes in community composition, see § 8.4.3(E) of this
Part.
2. During the construction
and decommissioning phases of a project, the eggs and larvae of many species of
fish may be vulnerable to being buried or removed. Some species, such as
herring and sand eels, lay their eggs in the substrate; if wind farm
construction took place within the spawning grounds of these species, it would
likely impact the species (BMT Cordah Limited 2003). Other benthic organisms
may also be buried in the process, which could affect finfish and shellfish
that rely on these organisms for food. Individual fish are likely to move out
of the area during construction because of the disturbance and because of the
loss of food (MMS 2007a). After the activity has ceased, recolonization may
take months or years (Gill 2005).
3. No detailed, long-term analyses have yet
been conducted on entire fish assemblages around either decommissioned oil
platforms (a suitable comparable development of the coastal environment) or
wind energy projects (Ehrich et al. 2006). Ehrich et
al. (2006) hypothesize that any effects on fish densities and
diversity resulting from newly installed wind turbines will be restricted to
the immediate vicinity of the structures, and will not have wide-reaching
effects, unless rare species are directly affected, which could have effects at
the population level. The authors also note that in cases where wind turbines
are constructed in areas with a sandy bottom, there may be localized removal of
species dependent on soft-bottom habitat, favoring species which prefer hard
bottoms, as the hard structures serve as habitat for these species. As most
wind farms thus far have been constructed in areas of sandy bottom, there is
little data on changes to other types of benthic habitats. They suggest that
the wind farms will also favor large predators, particularly if fishing
pressure among the turbines is reduced (Ehrich et al.
2006).
4. There may also be changes
in predator-prey relationships, in which some predators move out of the area
temporarily or have their numbers temporarily reduced during the construction
phase. This can result in the process of competitive release, in which species
preyed upon by these predators become available to other predators. Often it is
smaller species with faster rates of reproduction that will replace existing
species. This could have secondary effects elsewhere, if the numbers of
predators increase outside of the area of development (Gill and Kimber
2005).
5. The decommissioning of
wind turbines would also have significant ecological effects, as the new
habitat and accompanying species are removed. Habitat heterogeneity and the
abundance of species would be reduced.
H. Structures (formerly § 850.7.6)
1. Organisms may either collide with or avoid
the wind turbine structures underwater. While little information is available
regarding this topic, the greatest impacts are likely to be within enclosed
waters or where the devices form a barrier to movement (Gill 2005); thus
collision and avoidance are not likely to be major impacts of the proposed wind
turbines in the Ocean SAMP area.
I. Reef effect (formerly § 850.7.7)
1. As noted above in § 8.4.3(D), wind
turbine structures may serve as both artificial reefs, in providing surfaces
for non-mobile species to grow on and shelter for small fish, and as fish
aggregating devices, which are used to enhance catches by attracting fish
(Wilhelmsson et al. 2006).
2. After the wind turbines are in place, a
change in the type and abundance of benthic species can be expected, which will
change food availability for higher trophic levels. Because the placement of
wind turbines may increase habitat for benthic species, the structures may have
the effect of increasing local food availability, which may bring some species
into the area. This may increase use of the area by immigrant fauna. More
adaptable species will probably dominate the area under these new ecological
conditions. The change in prey size, type, and abundance in the vicinity of the
structures may also affect predators. Predators moving into the area may result
in prey depletion (Gill 2005).
3.
Oil and gas platforms have been found to harbor large numbers of larval and
juvenile fish, and wind turbine support structure can be expected to have a
similar effect. Because the structures extend throughout the water column,
juvenile or larval fish are more likely to encounter them than other habitat
types found only on the bottom, and may be more likely to settle there. There
may also be less predation on small fish in midwater habitats, so they can
safely hide in the structure at a variety of depths (Love et
al. 2003). Fish can take advantage of the shelter provided by the
structures while being exposed to stronger currents created by the structures,
which generate more plankton for plankton-eating fish (Wilhelmsson et
al. 2006). While colonization of the new structures will begin shortly
after construction, it will usually take several years for the colonization to
be completed, because not all species will colonize the area at once (DONG
Energy et al. 2006) and there will be a succession of species and a likely
increase in species using the newly formed community hence increasing
diversity.
4. Wind turbines may
also provide refuge from predation for juveniles of a number of mobile species,
which is critical in promoting growth and survival until they reach maturity.
Similarly, the structures may also provide refuge for both large and small fish
and other species from fishing pressure. In the UK, where fishing is currently
not permitted around the structures, they are being promoted as protected
areas, and may eventually contribute to stock replenishment for some species.
These structures have not yet been in the water long enough to see these
effects; however, many of the juvenile fish found around the turbines are small
Gadoid species such as cod. Additionally, if there is an absence of trawling
and dredging between the wind farms, it may result in increases in benthic
fauna (DONG Energy et al. 2006; Kaiser et al.
2000). Even if fishing is permitted, most fishermen are unlikely to fish
immediately next to the turbines because of the possibility of having gear
tangled in the structures (see § 8.4.8 of this Part). In oil and gas
platforms, fish that remain within the jacketed structures may be less
vulnerable to fishing pressure than others (Love et al. 2003).
In addition to fish, these structures may also provide important habitat for
lobsters and crabs. Young, newly-settled individuals of these species typically
seek out refuge to avoid predation, including hiding among stones and cobbles,
or burying in sediments. Wind turbines and scour protection may provide
suitable hiding places for these individuals, and may enhance the lobster
fishery in cases where habitat is a limiting factor (Linley et
al. 2007).
5. A number of
studies of decommissioned oil platforms have indicated fish are attracted by
the structures (Ehrich et al. 2006). A study conducted on oil
and gas platforms off the Californian coast found that the platforms tended to
have higher abundances of large, commercially targeted fish than did natural
reefs. This result may have been because of low fishing activity around the
platforms, creating de facto marine protected areas. Generally, the platforms
also had higher numbers of young-of-the-year rockfish than other areas,
including natural reefs (Love and Schroeder 2006). One study noted the tendency
of large, recreationally targeted species such as tunas and mackerel to
associate with fish aggregating devices, and predicted wind turbines might have
the same effect (Fayram and de Risi 2007). A study of decommissioned oil rigs
in the North Sea off Norway found aggregations of cod, mackerel, and other
species around the structures (Soldal et al. 2002).
6. The observed effect of other wind turbines
has found some species are attracted to wind farms. A study of wind farms in
Danish waters found the increased habitat heterogeneity from turbine
foundations resulted in an increase of species from adjacent hard surfaces,
leading to a local increase in biomass of 50 to 150 times, most of which served
as available food for fish and seabirds (DONG Energy et al.
2006). Monitoring of the Horns Rev wind farm in Denmark found a 300% increase
in the number of sand eels around the wind turbines between 2002 and 2004, and
an eight-fold increase in the availability of food for fish in the area, but
not a statistically significant difference in the number of fish (DONG Energy
and Vattenfall 2006). Another study found an increased number of cod in the
area surrounding wind turbines at the Vindeby Offshore Wind Farm in Denmark
(Bioconsult A/S 2002). Some studies have not found an increase in fish around
structures; this may be because the studies were conducted during the early
stages of colonization (DONG Energy et al. 2006).
7. One question to be determined about wind
turbines is whether they actually increase fish populations by providing
habitat, or simply attract fish from elsewhere, concentrating them in the area
of the structure. If individual fish are being attracted to the site, but
populations are not increasing, this may have impacts on adjacent habitats
where the fish would ordinarily be found (Gill 2005). If the structures serve
only to aggregate fish and not to produce additional biomass, there is a risk
of harvesting pressure around the structures leading to overexploitation of
certain stocks by concentrating the fish and leaving them more vulnerable to
harvesting (Whitmarsh et al. 2008).
8. Love and Schroeder (2006) found that in
some instances, the fish found at the platforms were producing significant
amounts of larvae that may have been increasing populations around the
platforms and elsewhere. They also found that while some of the fish present
around oil and gas platforms were adults of species that had likely migrated
from elsewhere, the majority of individuals for many species were small
juveniles that had likely been brought to the platforms as plankton and settled
there (Love et al. 2003). Love and Schroeder (2006) also found
that juvenile fish living around oil and gas platforms had lower predation
rates than fish living on natural reefs, because of a low density of predators
in the mid- and upper waters around the platforms, and that there appeared to
be no difference in growth rates between fish living on platforms or on natural
reefs.
J. Decommissioning
effects (formerly § 850.7.8)
1. As
discussed above, wind turbine structures may serve as artificial reefs,
providing habitat for a number of invertebrate and fish species, especially
juvenile fish. As such, the eventual decommissioning of the turbines could have
negative environmental impacts by reducing or removing this habitat. While this
issue has not yet been dealt with for offshore wind energy projects, the debate
over how to best decommission oil and gas platforms has been ongoing in
California and the Gulf of Mexico. For oil and gas platforms, it is estimated
that the life of a decommissioned platform left in place will be from 100 to
more than 300 years (Love et al. 2003). A large-scale wind
farm will occupy more seabed space than individual oil and gas rigs, and thus
the area of the ocean floor affected by both construction and decommissioning
will be larger than for oil and gas rigs. The decommissioning of the wind
turbines and the resulting effects on fish and fisheries should be
considered.
8.4.8 Commercial and Recreational Fishing (formerly § 850.8)
A.
Offshore renewable energy may affect commercial and recreational fisheries
activity in many different ways. Some of the potential effects on fishermen
from the placement of a wind farm in the Ocean SAMP area may include changing
the distribution and/or abundance of fish populations, increasing stocks of
certain fish through reef effects; limiting fishermen's access to traditional
fishing grounds; gear or vessel damage; and other changes to fishing
activities. These general types of effects are discussed below, though specific
effects are dependent on site-specific conditions such as location, type and
scale of project, and other factors. The potential site-specific effects of an
offshore renewable energy project in the Ocean SAMP area will undergo in-depth
evaluation as part of the permitting process (see Section 820.4 and Chapter 10,
Existing Statutes, Regulations and Policies).
B. Effects on fish populations (formerly
§ 850.8.1)
1. Some fish species,
especially rare or overfished species, could be negatively affected by the
presence of wind farms if the wind farms result in a localized concentration of
fishing effort and an increased harvest if the species are attracted to the
structures. Alternatively, the increased habitat for some species created by
the structures may result in increased populations of commercially important
species (see § 8.4.7(I) of this Part), leading to economic gains for
commercial fishermen targeting these species (BMT Cordah Limited 2003), and
increased opportunities for recreational anglers, who are likely to focus their
efforts around the wind turbines.
2. There is also the potential for secondary
effects on fish populations if fishermen are displaced from the wind farm area,
and as a result concentrate their efforts elsewhere on vulnerable populations
or habitats (BMT Cordah Limited 2003). Likewise, if the wind turbines serve as
fish aggregating devices, attracting and concentrating fish from elsewhere in
the Ocean SAMP area, and attracting more commercial and recreational fishing
activity to the area to take advantage of the aggregation, it could have the
undesired outcome of leaving fish species more vulnerable to overharvesting
from more concentrated fishing effort (Whitmarsh et al.
2008).
3. Fish populations could be
affected by some or a combination of the factors listed in § 8.4.7 of this
Part, such as noise or electromagnetic fields, which could potentially have
effects at the population levels if activities such as spawning or feeding are
affected. Some fish populations could also be affected by a change in benthic
habitat as some areas of the seafloor are converted to hard structures. The
cumulative effects of the factors mentioned above may also need to be
considered. For more on the ways in which wind farms may affect fish, see
§ 8.4.7 of this Part.
C. Effects on fish catch (formerly §
850.8.2)
1. Negative impacts to fish catches
may be greatest during the construction phase, when the noise generated by
construction activities may drive some mobile species out of the immediate
area.
2. Engås et al. (1996)
found the average catch rates for cod to decrease by about 50% both in the
immediate vicinity of and at a distance from air gun activity. Haddock catches
also decreased by similar percentages. Five days after the air gun was used,
fish catches had not increased. However, as noted above, air guns are unlikely
to be used in the pre-construction siting process.
3. Positive impacts to fish catch may occur
during the operational phase as a result of reef effects if there is a
resulting increase in or aggregation of biomass around the turbine structures.
If there is an increase in fish in the vicinity of the turbines, this could
benefit fishermen, particularly recreational and commercial rod and reel
fishermen, who may be most easily able to target these fish.
4. Westerberg (1994, 2000, as reported in
Thomsen et al. 2006) found that catches of cod decreased
within 100m [328 ft] of a wind turbine while it was operating, likely because
of the noise generated by the turbine itself. The study also found higher
catches within 100m [328 ft] of the turbines than in the surrounding areas when
the turbines were stopped, likely because of the reef effect (for more on the
reef effect and fisheries, see § 8.4.7(I) of this Part). However, in a
separate study, Wahlberg and Westerberg (2005) estimated that the levels of
noise produced by operating turbines (1.5 MW) were only likely to cause
avoidance responses by fish closer than 4 m [13 ft] to the turbines and only at
high wind speeds (13 m/s [29.1 mph]). They also noted that fish may habituate
to the noise created by the wind turbines and disregard the sound. The
potential effect of operational noise on fish may vary between projects, as
operational noise will varies depending on the turbine size, model, foundation
type and speed of rotation (see § 8.4.5(H) of this Part).
5. In a study by Vella et al. (2001), the
catch per unit effort (CPUE) of cod (Gadus morhua) and
shorthorn sculpin (Myoxocephalus scorpius) was greater within
200 m [656 ft] of a wind turbine than between 200 - 400 m [ 656-1,312 ft] of a
turbine, regardless of whether the turbine was operational or not. The study
did find that CPUE was lower in the vicinity of the turbine while the turbine
was operational, but still higher than in the area 200 - 400 m from the
turbine. This indicates that the turbine may be increasing catch because it is
acting as a fish aggregating device (Rodmell and Johnson
2005).
D. Access to
fishing grounds (formerly § 850.8.3)
1.
Offshore renewable energy facilities may have an adverse impact on commercial
and recreational fishermen's access to traditional fishing grounds. The degree
of impact varies significantly by facility design, stage of the development
process, location in the offshore environment, and type of fishing activity,
and may be either temporary or long-term. Fishermen may be displaced from
traditional fishing grounds by the structures themselves, regulatory decisions
that limit access around the structures or through the facility, or other
factors.
2. Fishing access around
existing offshore renewable energy facilities in Belgium, Germany, the
Netherlands, and the United Kingdom is subject to restrictions imposed by those
countries' respective governments. In Belgium, Germany, and the Netherlands, a
500-meter Safety Zone is established around the entire wind farm, and fishing
is prohibited within this area. In the United Kingdom, a 500-meter [0.3 mi]
Safety Zone is established around each individual turbine only during the
construction period. During operation, a 50-meter [164 ft] Safety Zone is
established around each individual turbine. These restrictions are primarily
instituted for safety reasons and are similar to those applied to offshore oil
and gas rigs in these same countries (except for Belgium, where there are no
rigs).
3. In the Ocean SAMP area
and other U.S. waters, access around individual turbines or through wind farms
is the jurisdiction of the U.S. Coast Guard, in partnership with the U.S. Army
Corps of Engineers (in state waters) and the U.S. Bureau of Ocean Energy
Management, Regulation and Enforcement (in federal waters). At the time of this
writing, there is no formal policy in place that would universally limit
fishing or navigational access around and through offshore wind farms in U.S.
waters. In addition, as a point of reference, it should be noted that safety
zones are not universally established at Gulf of Mexico offshore oil and gas
platforms. Those few platform specific safety zones that are in place are
designed to address site- and activity-specific safety issues and typically
allow recreational activities, including recreational fishing (LeBlanc, pers.
comm.).
4. Fishing activity will be
affected differently through different stages of the development process.
Fishing vessels may be required or may choose to avoid the area during the
construction process to avoid conflict with construction activities and
vessels. During the operation phase, fishermen may be required or may choose to
avoid the turbines because of the potential risk to their vessels or fishing
gear from collision with a turbine, snagging gear, or other safety
concerns.
5. The potential impacts
of offshore renewable energy on fisheries activity varies by gear type. The
PEIS (MMS 2007a) indicates that bottom trawling has the greatest potential for
conflict with offshore facilities because of the potential for snagging bottom
gear on cables and debris. It further indicates that surface longlining may
encounter water-sheet use conflicts with renewable energy facility construction
and service vessels.
6. If certain
gear or vessel types are restricted from the wind farms, either for safety and
navigational reasons, or because those fishermen choose to fish elsewhere
because of the difficulty of navigating amongst the turbines, this may actually
benefit competing gear types fishing for the same species within the wind
farms. The presence of a wind farm may significantly alter the patterns of
fishing within the area (North Western and North Wales Sea Fisheries Committee
n.d.).
7. A loss of fishing grounds
from the placement of a wind farm could cause vessels to have to travel further
to fishing grounds (BMT Cordah Limited 2003), increasing fuel costs and
potentially risks to safety. This could have a disproportionate impact on
smaller fishing vessels, to which the risks of venturing further to sea will be
greater.
8. Some fishermen have
expressed the concern that marine insurance companies might increase their
insurance premiums or prohibit insured fishing vessels from operating within
the vicinity of offshore wind farms (e.g. Ichthys Marine 2009). However, it
should be noted that at the time of this writing, Sunderland Marine does not
currently impose restrictions or higher premiums on their members, nor have
they heard of other insurance companies issuing such demands (McBurnie, pers.
comm.). Sunderland Marine is the world's largest insurer of fishing vessels,
and insures The Point Club, a fishing vessel insurance and safety club that
insures many of the fishing vessels operating out of Point Judith and Newport
(Nixon, pers. comm.).
E.
Gear/vessel damage (formerly § 850.8.4)
1. Wind farms may present a navigational
hazard for fishing and other vessels, and there is some risk of collision with
turbines, or with service vessels. Power cables and bottom fishing gear present
mutual possibilities for damage, and may endanger the safety of fishing
vessels. Burying cables between the turbines, as well as from the wind farm to
shore, will mitigate some of this problem. However, even if cables are buried,
there is a potential for them to become uncovered through sea bed movement,
putting a trawled net and perhaps the fishing vessel in danger of hang ups
(Rodmell and Johnson 2005). Rodmell and Johnson (2005) note that single vessel
trawling within and around the wind turbines may be possible if cables are
sufficiently buried or protected, but that pair trawling may not be practical,
and scallop dredging may not be compatible with wind farms.
2. Long lining and gill nets may be feasible
in the vicinity of wind turbines, although their lengths may need to be limited
depending on the spacing of the turbines. Purse seining within the wind farms
is likely to be difficult, although may be possible on a small scale. The use
of lobster and fish pots in the vicinity of the wind turbines should be mostly
undisturbed. Even if fishing activity is permitted within the wind farms,
fishing vessels may prefer to avoid navigating within and through wind farms
(Rodmell and Johnson 2005).
F. Changes to fishing activity (formerly
§ 850.8.5)
1. The presence of wind farms
may impede access to fishing grounds for some fishermen; even if fishing within
the turbines is not restricted, some fishermen may choose to avoid the wind
farms for safety or insurance reasons, and may have to travel further to fish,
making it harder or more costly to retain the same level of catch. The greatest
impacts may be to smaller vessels, which may be more limited in their ability
to fish elsewhere. This may also result in increased competition for space in
other areas (Rodmell and Johnson 2005). Those vessels most likely to have to
avoid the wind farm areas will be those with towed or static nets (Mackinson
et al. 2006), which in the Ocean SAMP waters includes
primarily trawlers and scallop dredges. As many trawlers are targeting
groundfish, already a vulnerable fishery due to declining catches and
increasing regulations, groundfishing vessels may be the most vulnerable to
possible increased costs or reduced earnings from displacement.
2. Fishermen interviewed in the UK were
concerned that if they were displaced from their usual fishing grounds, they
would have to spend time searching for new fishing grounds, and that if there
were insufficient resources in the new fishing grounds to support them, they
would inevitably suffer from a reduction in catch. If the fishermen are
displaced, they may also suffer a reduction in catch because of the time
required to search for and develop the specialized local knowledge of their new
fishing grounds they have held at their previous grounds. Fishermen relocated
to another area may suffer reduced earnings because they are competing with
vessels already fishing in the area, or, in the case that a larger vessel is
displaced and seeks out new fishing grounds, it may in turn displace smaller
vessels fishing already fishing in the new area (Mackinson et
al. 2006).
3. Fishermen in
the UK were concerned about impacts on the availability and cost of insurance
for fishing vessels navigating around wind farms, even if fishing within wind
farms is legal (Mackinson et al. 2006).
4. If the wind turbine support structures
serve as artificial reefs or fish aggregating devices, they could have positive
economic benefits for some commercial fishermen through increased catch rates.
A study of artificial reefs off Portugal found that fishing around the
artificial reefs resulted in substantially higher revenues, and that the value
per unit of effort was also greater, because the fish were more concentrated
(Whitmarsh et al. 2008). These benefits would likely only
accrue to fishermen able to fish in the vicinity of the structures, although if
the reef effects of the turbine support structures serve to increase fish
biomass overall, this could benefit all fishermen in terms of spillover to
adjacent habitats and thereby increased catches. There is also a danger that
the economic benefits from fish aggregation and the resulting increase in catch
efficiency around the turbines could lead to overexploitation of stocks and
decrease catches elsewhere, negating any positive benefits to be had (Whitmarsh
et al. 2008).
5.
Any reef effect would also have positive benefits for recreational anglers, who
would likely be drawn to the area and may have more opportunities for fishing.
This could have secondary economic effects by increasing recreational fishing
activity and thus expenditures in the Ocean SAMP area.
6. Fishing incomes may be supplemented or
enhanced by offshore aquaculture activities that may be based around the wind
turbines. For more on this potential future use, see Chapter 9, Other Future
Uses.
8.4.9 Cultural and Historic Resources (formerly § 850.9)
A. The potential effects of offshore
renewable energy on cultural and historic resources may include physical
impacts on existing offshore submerged archaeological resources such as
shipwrecks or pre-contact settlements on the ocean floor, as well as visual
impacts when the development is proposed within the viewshed of onshore
land-based sites designated as historically significant.
B. Research and documentation of the effects
of offshore renewable energy on cultural and historic resources have been
compiled for projects in Europe, and during review for the Cape Wind project
proposal in the United States (MMS 2010). In anticipation of future offshore
renewable energy development within the U.S., BOEM has identified potential
impacts and enhancements of such development on cultural and visual resources
in the PEIS (MMS 2007a). From Europe, the Collaborative Offshore Wind Research
Into the Environment (COWRIE) released, "Guidance for Assessment of Cumulative
Impacts on the Historic Environment from Offshore Renewable Energy", that
identifies both synergistic and cumulative impacts on cultural and historic
resources (COWRIE 2007).
C. The
term "Area of Potential Effect" (APE) is defined under the federal National
Historic Preservation Act (36 C.F.R. §§
800.1
through 800.16) as the areas within which
a project may directly or indirectly alter the character or use of historic
properties. For offshore development proposals, BOEM defines an APE for direct
impacts to include both offshore submerged areas and onshore land-based sites
where physical disturbance would be required for construction, operation,
maintenance, and decommissioning. The APE for submerged areas includes
footprints of proposed structures to be secured on the ocean floor and related
work area as well as all related bottom-disturbing activities, including, but
not limited to, barges, anchorages, appurtenances, and cable routes where ocean
sediments and sub-bottom may be disturbed. (MMS 2010). For onshore sites, the
APE would include any soil disturbance required for cables or connections to
onshore electric transmission cable systems, or visual impacts specifically
related to National Historic Landmarks, and other properties listed or eligible
for listing on the National Register of Historic Places, including Traditional
Cultural Properties (MMS 2010).
D.
The construction of offshore renewable energy facilities may result in direct
disturbance of offshore submerged archaeological resources, including shipwreck
sites and potential settlements that may have existed on what is now the ocean
floor. The maps presented in Section 420.4 illustrate a paleo-geographic
landscape reconstruction that suggests much of the area that is now Block
Island and Rhode Island Sound was dry land over 12,500 years Before Present
(yBP), and that human settlement in these areas was possible. Any disturbance
of the bottom could potentially affect any cultural resources present,
including early settlement sites; the level of impact may depend on the number
and importance of cultural resources in that location, and any seabed
disturbance that has occurred previously in the location (MMS 2007a). BOEM
requires if any unanticipated cultural resources are encountered during a
project, all activities within the area must be stopped and BOEM be consulted
(MMS 2007a).
E. For offshore
development proposals, an Area of Potential Effect (APE) for indirect impacts
is defined to include the area within which the final project as well as the
various phases of construction will be notably visible. Visual impacts to the
setting, character and other aspects of onshore land-based sites may result
from the final project as well as the various phases of construction in an
offshore renewable energy project. If turbines were visible from shore, this
would represent a change in the viewshed and an alteration of the aesthetics of
the visual setting of areas where the structures were visible. For onshore
land-based sites, the overall perception of visual impacts of offshore
developments is subjective and opinions vary about whether visual impacts for a
given project are positive, negative, or neutral (MMS 2007a). In advance of the
construction phase, a meteorological tower will likely be installed in the
project area to collect data to assess the wind resources. The visual impact of
the tower will depend on its distance and thus visibility from shore. During
the construction, operation and decommissioning phases, there will be increased
vessel traffic in the project area, which will alter the visual characteristics
of this area in that many of the construction and maintenance vessels,
including a variety of ships and crane/jack-up barges, may be larger in size
than other vessels traditionally in use within the project area (MMS 2009a).
The FAA will likely require aircraft warning lights on the turbines for air
safety purposes; these will be single red lights that flash at night on the
nacelles of the peripheral turbines. Whether these lights are visible from
land, and thus have an effect on land-based viewing, will depend on whether the
turbines themselves are visible from land (MMS 2009a).
F. Section 106 of the National Historic
Preservation Act, however, requires that a given project's visual effect on
historic resources be evaluated for National Historic Landmarks and other
properties listed or eligible for listing on the National Register of Historic
Places, including Traditional Cultural Properties (MMS 2010). If there is a
potential visual effect, it must be evaluated to determine what effect, if any,
it would have on significant historic resources. A project may be found to
have: no effect; no adverse effect if the visual impact is limited and
insignificant; or an adverse effect. Adverse effects are defined by the
Criteria of Adverse Effect in the Section 106 procedures of the National
Historic Preservation Act [36 C.F.R. §
800.5(a)(1)], which state,
"An adverse effect is found when an undertaking may alter, directly or
indirectly, any of the characteristics of a historic property for inclusion in
the National Register in a manner that would diminish the integrity of the
property's location, design, setting, materials, workmanship, feeling, or
association." Examples of adverse effects relevant to the development of
offshore renewable energy are listed as including, but not limited to, the
following [36 C.F.R. §
800.5(a)(2)] : "Alteration
of a property...; Change of the character of the property's use or of physical
features within the property's setting that contribute to its historic
significance...; Introduction of visual, atmospheric or audible elements that
diminish the integrity of the property's significant historic features."
Adverse effects from visual impacts may be further evaluated in the case of
National Historic Landmarks to determine if they are indirect impacts or direct
impacts, which diminish the core significance of the National Historic Landmark
(Advisory Council on Historic Preservation, 2010).
G. The magnitude of the visual impacts will
depend on site- and project-specific factors, including: distance of the
proposed wind facility from shore; size of the facility (i.e., number of wind
turbines); size (particularly height) of the wind turbines; surface treatment
(primarily color) of wind turbines and electrical service platforms (ESPs);
number and type of viewers (e.g., residents, tourists, workers); viewer
location (onshore vs. offshore); viewer attitudes toward alternative energy and
wind power; visual quality and sensitivity of the landscape/seascape; existing
level of development and activities in the wind facility area and nearby
onshore areas (i.e., scenic integrity and visual absorption capability);
presence of sensitive visual and cultural resources; weather conditions;
lighting conditions; and presence and arrangements of aviation and navigation
lights on the wind turbines (MMS 2007a).
H. Factors that influence the perception an
evaluation of visual impacts include: viewer distance; view duration;
visibility factors; seasonal and lighting conditions; landscape/seascape
setting; number of viewers; and viewer activity, sensitivity, and cultural
factors (MMS 2007a).
8.4.10 Recreation and Tourism (formerly § 850.10)
A. The potential
effects of offshore renewable energy on recreational and tourism activities are
not well understood given the relatively recent occurrence of offshore
renewable energy. The PEIS indicated that offshore renewable energy
installations might have visual impacts on marine recreational users and
coastal tourists, though this depends on the location and visibility of the
structures, as well as the preferences of the individual (MMS 2007a). Visual
impacts may be caused by the offshore structures themselves, as well as the
sights of support vessels, construction equipment, and helicopters traveling to
and from offshore facilities, which may impact cruise ship tourists, coastal
tourists, beach users, and recreational boaters. Such impacts could result in
the reduction of tourism or recreational activity within sight of the project
area (Lilley et al. 2009). BOEM cites no evidence of such
impacts in other locations with offshore renewable facilities and indicates
that such impacts, if any, are expected to be minor (MMS 2007a).
B. Alternatively, the PEIS also indicates
that offshore renewable energy structures may enhance marine recreational and
tourism activities by becoming an attraction that recreational boaters, charter
boat clients, cruise ship passengers, and other visitors may want to visit (MMS
2007a). A 2007 University of Delaware study found that 65.8% of surveyed
out-of-state tourists were likely to visit a beach in order to see a wind farm
offshore, and 44.5% were likely to pay to take a boat tour of an offshore wind
facility (Lilley et al. 2009). Anecdotal data provided by a
2006 British Wind Energy Association study indicates several instances in which
tourism increased at UK destinations adjacent to offshore wind farms, or where
surveyed tourists indicated that the wind farm had no effect on their
likelihood to visit the site (British Wind Energy Association 2006). Visitor
centers have been developed at some of these sites to facilitate tourists'
experience (British Wind Energy Association 2006).
C. Noise associated with on-site marine
construction, or traffic noise from support vessels and helicopters traveling
to and from the offshore facility, may have a potential impact on coastal
tourists and marine recreational users. Such impacts could result in the
reduction of tourism or recreational activity within the affected area. In the
PEIS, BOEM cites no evidence of such impacts in other locations with offshore
renewable facilities and indicates that such impacts, if any, are expected to
be minor (MMS 2007a).
D. The
construction and operation of offshore renewable energy facilities may result
in short- or long-term displacement of marine recreational users, particularly
recreational boaters. The construction phase may result in temporary closures
of the offshore project area and/or adjacent shoreline areas during activities
such as driving piles or installing transmission cables. Though less likely,
the operation phase may also result in the long-term displacement of
recreational users from all or part of the project area. Such temporary or
long-term closures could alter recreational activities and use patterns within
the Ocean SAMP area by lengthening transit times between destinations,
displacing fishing activities conducted by income-generating charter boat
operations, or displacing large-scale sailboat races that rely on the use of
the project area. Such a displacement could also cause individual users or
entire events to relocate, resulting in increased recreational activity in
other in-state or out-of-state locations (MMS 2007a; Royal Yachting Association
and the Cruising Association 2004). In the PEIS, BOEM indicates that such
impacts, if any, are expected to be minor (MMS 2007a). It should also be noted
that enforcing access restrictions around an offshore renewable energy facility
may be very difficult given the offshore location.
E. The construction and operation of offshore
renewable energy facilities may impact navigation and marine safety for
recreational boaters in and around the project area. Alternatively, offshore
facilities may provide enhancements to navigation and marine safety by
providing mariners access to offshore weather data. Such impacts, enhancements,
and mitigation measures are discussed at length in § 8.4.11 of this Part
which deals with potential affects to marine transportation, navigation, and
infrastructure.
F. Some of the
recreational uses discussed in Chapter 6, Recreation and Tourism rely on the
presence and visibility of marine and avian species including fish, whales,
sharks, and birds. Offshore renewable energy facilities may have some impacts
on these species and/or the habitats on which they rely. Alternatively,
offshore renewable energy support structures may add to habitat complexity and
increase biodiversity within the immediate area, attracting more fish, birds,
whales and sharks, thereby improving recreational activities that rely on these
species. See §§ 8.4.3, 8.4.4, 8.4.5 and 8.4.7 of this Part for more
information on the potential affects offshore renewable energy development may
pose to these resources.
G. If
offshore renewable energy development results in a reduction in marine
recreation and tourism in the Ocean SAMP area, Rhode Island-based businesses
that serve these industries may lose some business. Alternatively, marine
trades and coastal tourism businesses may benefit from offshore renewable
energy in response to the potential growth of marine and coastal tourism
activities such as wind farm boat trips (OSPAR 2004) (see above). In addition
the construction and operation of an offshore facility may require additional
shore-based infrastructure or services that may boost the marine trades
sector.
8.4.11 Marine Transportation, Navigation and Infrastructure (formerly § 850.11)
A. Offshore renewable energy
may have some effects on marine transportation, navigation activities and other
infrastructure in the Ocean SAMP area. The degree to which offshore renewable
energy structures may affect marine transportation, navigation and
infrastructure varies in large part on the specific siting of a project.
Careful consideration when planning the location of an offshore renewable
energy facility, as well as the use of appropriate mitigation strategies, can
minimize any potential negative impacts (MMS 2007a).
B. In addition to the potential effects
identified in European research, the PEIS and the Cape Wind FEIS, the U.S.
Coast Guard has issued a Navigation and Vessel Inspection Circular (U.S. Coast
Guard NAVIC 02-07) to provide guidance on the information and factors the Coast
Guard will consider, which include navigational safety and security, when
reviewing a permit application for an offshore renewable energy installation in
the navigable waters of the United States (U.S. Coast Guard 2007).
C. Offshore renewable energy facilities may
affect navigational safety in a project area by increasing the risk of
collision, limiting visibility, or limiting a vessel's ability to maneuver (MMS
2007a; U.S. Coast Guard 2007; BWEA 2007; U.K. Maritime and Coast Guard Agency
2008). However, collision risk was found to be low, especially when facilities
are sited appropriately (e.g. MMS 2007a). Risks that have been identified
include vessels colliding with offshore renewable structures themselves; with
other vessels; or with ice that has formed on or around the structures during
winter months. Moreover, visibility may be impaired surrounding an offshore
renewable energy facility, as structures may block or hinder a mariner's view
of other vessels, nearby land masses, or other navigational features (U.S.
Coast Guard 2007; United Kingdom Maritime and Coast Guard Agency 2008).
Obstructed visibility could potentially put a vessel at risk of collision or
running aground. However, mitigation measures have been identified that can
lower this potential risk to acceptable levels. For instance, mariners have
been advised to follow required standard operating procedures, where
applicable, as outlined in the International Regulations for Preventing
Collisions at Sea (COLREGS) for limited visibility conditions. Adherence with
these standard regulations can mitigate hazards to navigation caused by
impaired visibility within an offshore renewable energy facility (U.S. Coast
Guard 2009; U.K. Maritime and Coast Guard Agency 2008). Offshore renewable
energy structures may also limit the ability of some larger vessels to maneuver
to avoid collision, as these vessels usually require greater stopping distances
and have wider turning radii (U.S. Coast Guard 2007; U.S. Coast Guard 2009).
The PEIS notes that such impacts can be mitigated to acceptable levels by
siting offshore renewable energy facilities so that they do not interfere with
designated fairways or shipping lanes, and using appropriate signage and/or
lighting to warn passing vessels (MMS 2007a; U.S. Coast Guard 2009). In
addition, the U.S. Coast Guard considers all of these navigational safety
issues when evaluating a permit application for an offshore renewable energy
structure (U.S. Coast Guard 2007).
D. Whereas offshore renewable energy
facilities may potentially displace marine transportation, military, or
navigation uses, appropriate siting away from shipping lanes, military usage
areas, or other intensively-used areas can minimize or eliminate any potential
displacement of these uses (MMS 2007a). Vessels that cannot safely operate or
navigate within an offshore renewable energy facility may be excluded from
areas that were previously used, and therefore would need to alter travel
routes in the vicinity of such projects (United Kingdom Maritime and Coastguard
Agency 2008; U.S. Coast Guard 2007). Route alterations may potentially extend
vessel travel times. The PEIS (MMS 2007a) notes that such impacts can be
mitigated to acceptable levels by siting offshore renewable energy facilities
away from designated fairways or shipping lanes. In addition, BOEM (MMS 2007a)
expects that the military impacts of offshore wind farms will be negligible
provided that development is coordinated with the U.S. Department of Defense
and all appropriate military agencies.
E. Offshore renewable energy structures may
affect the physical characteristics of a waterway, which include localized
currents and sediment deposition and erosion (United Kingdom Maritime and
Coastguard Agency 2008) though can be minimized to acceptable levels through
proper siting and mitigation methods (U.S. Coast Guard 2007; MMS 2007a).
Currents that are altered in direction and/or speed within or around an
offshore renewable energy facility, may affect how vessels navigate through an
area. In addition, structures that attach to the seafloor or extend through the
water column may affect the surrounding water depth by altering sediment
movement or deposition (MMS 2007a; U.S. Coast Guard 2007; United Kingdom
Maritime and Coastguard Agency 2008). Consequently, if shoaling occurs, vessel
navigation may be impacted within or around an offshore renewable energy
facility. These effects may be most pronounced in predominantly shallow areas,
or areas composed of highly mobile substrate (i.e. sands) with strong waves or
currents. Mitigation measures may include installing scour-protection devices
and monitoring sediment transport processes (United Kingdom Maritime and
Coastguard Agency 2008; U.S. Coast Guard 2007; MMS 2007a). For more information
on scour and the potential effects to coastal processes and physical
oceanography see § 8.4.2 of this Part.
F. Due to the large size of some offshore
renewable structures, offshore renewable energy installations may interfere
with the use of radar by ships or shore-based facilities within the area.
However, interference may be negligible to minor when properly mitigated (MMS
2007a; U.S. Coast Guard 2007; Technology Service Corporation 2008; Howard and
Brown 2004; U.S. Department of Defense 2006). Studies have shown that ship and
land-based radar systems may have some difficulty in detecting marine targets
within an offshore renewable energy facility as the result of the distortion or
degradation of radar signals by the installed structures (U.S. Coast Guard
2009; Technology Service Corporation 2008; MMS 2007a; U.S. Department of
Defense 2006, BWEA 2007). Research conducted to assess the potential radar
impacts of the proposed Cape Wind project in Nantucket Sound found that the
facility would only pose adverse impacts in accurately detecting targets within
and immediately behind the wind farm, as the installed structures may produce
false targets or mask real targets (U.S. Coast Guard 2009; Technology Service
Corporation 2008; United Kingdom Maritime and Coastguard Agency 2008). In other
words, vessels navigating near but outside a wind farm may not be able to
clearly identify, by radar, another vessel operating within the wind farm due
to radar clutter. However, radar impacts observed within the wind farm can be
mitigated to acceptable levels through greater attention by radar operators in
distinguishing between real and false targets (U.S. Coast Guard 2009). No
adverse impacts were found to occur between vessels operating completely
outside, but within the vicinity of, the wind farm (U.S. Coast Guard 2009;
Technology Service Corporation 2008). Because the severity of impacts to radar
varies widely depending on site-specific characterizations, the U.S. Coast
Guard considers impacts on navigation radar when reviewing a permit application
(U.S. Coast Guard 2007).
G. Weather
radar located near offshore renewable energy installations may also be
adversely impacted by offshore renewable energy structures; impacts may include
misidentification of thunderstorm features, false radar estimates of
precipitation accumulation, and incorrect storm cell identification and
tracking (MMS 2007a).
H. The
installation of offshore renewable energy facilities may cause either minimal
impacts or possible enhancements to navigation and communication tools and
systems, including global positioning systems, magnetic compasses, cellular
phone communications, very-high frequency (VHF) communications, ultra-high
frequency (UHF) and other microwave systems, and automatic identification
systems (AIS) (MMS 2007a, United Kingdom Maritime and Coastguard Agency 2008).
The PEIS (MMS 2007a) indicates that any impacts are likely to be negligible to
minor, and cites a number of studies in which no negative impacts were found.
For example, Brown and Howard (2004) found no impact of wind farms on GPS
accuracy and also noted that magnetic compasses, AIS, and VHF communications
(ship-to-ship and ship-to-shore) were not affected within the wind farm
installation. The U.S. Coast Guard requires permit applicants to conduct
research on the potential impacts of an offshore renewable energy installation
on navigation and communication systems prior to construction (U.S. Coast Guard
2007).
I. Search and rescue
operations by agencies such as the U.S. Coast Guard, may be positively and/or
negatively affected by offshore renewable energy installations (U.S. Coast
Guard 2007; LeBlanc 2009). For example, installations may prolong the response
time of search and rescue missions in cases where longer routes around the
facility are required. Alternatively, offshore renewable energy structures may
provide refuge to distressed mariners stranded or disabled within the vicinity
of the facility (U.S. Coast Guard 2007). When evaluating an offshore renewable
energy permit, the U.S. Coast Guard will examine if an offshore renewable
energy facility will prolong an agency's response time during a rescue mission
(LeBlanc 2009). Previous research conducted to analyze the effects of offshore
wind farms on search and rescue operations, involving helicopters, showed that
radio communications and VHF homing systems worked satisfactorily, as did
thermal imaging of vessels, turbines, and personnel within the wind facility
(Brown 2005).
J. Operational
offshore renewable energy facilities may provide enhancements to navigation and
marine safety by providing mariners with access to in-situ offshore weather,
wave and current data. This information may increase navigational safety by
informing mariners of current offshore conditions, or providing a recent
history of offshore conditions to aid in search and rescue operations within
the area.
K. During the
construction of an offshore renewable energy facility, vessel traffic may
temporarily increase in a project area (MMS 2007a). Transits and operations of
vessels involved in the transport of equipment and materials, facility
construction, or the laying of submarine cables may temporarily increase (MMS
2007a). As a result, port facilities may also experience increased activity
(MMS 2007a). Increased vessel activity may continue, albeit to a lesser extent,
through the operation of the offshore renewable energy facility, as maintenance
vessels will be required to service the installed structures. The presence of
these vessels may increase the demand for port services, and enhance the
economic activity associated with port facilities and marine
industries.
L. Siting of offshore
renewable energy facilities near pre-existing submarine cables may impact the
security and accessibility of these cables. Such impacts can be mitigated to
acceptable levels by considering pre-existing cables when siting offshore
renewable energy facilities. Cable ships require a minimum distance from an
offshore structure in order to safely access a submarine cable for repair or
replacement (International Cable Protection Committee 2007). Offshore renewable
energy installations whose location does not allow for safe access to existing
submarine cables by the appropriate vessels may negatively impact the
operation, performance, and longevity of this infrastructure (International
Cable Protection Committee 2007). In addition, laying new submarine cables
associated with an offshore renewable energy facility may require crossing
existing cables in the area.
8.4.12 Cumulative Impacts (formerly § 850.12)
A. Table 8.20 in §
8.4.12(A)(1) of this Part summarizes of all the potential effects of offshore
renewable energy development on existing resources and uses identified in this
section. The range and severity of effects will vary depending on the project.
Project specific effects will be thoroughly examined as part of a project's
NEPA review. In order to assess what the net effect might be from any of these
effects related to offshore renewable energy, numerous factors will need to be
taken into account, including the duration, frequency, and/or intensity of the
effect. Furthermore, most effects are still not fully understood and will
require further monitoring (see §
8.5 of this Part for
monitoring requirements for offshore renewable energy in the Ocean SAMP area).
1. Table 8.20. Summary of potential effects
of offshore renewable energy development during each stage of development.
|
Area |
Pre-construction Siting |
Construction |
Operation |
Decommissioning |
|
Alteration of waves and currents |
N/A |
N/A |
Changes in current velocity and direction; changes in wave heights; Changes in larval distribution; Scour (local and global) |
N/A |
|
Water Column Density Stratification |
N/A |
N/A |
Reduced spatial extent of stratification; Shorter seasonal duration of stratification |
N/A |
|
Alteration of Benthic Habitat |
N/A |
Redistribution of sediments; Smothering of benthic organisms; smothering of eggs and larvae; damage to benthic habitat from cable sweep; Loss of habitat; disturbance to shellfish beds or hard bottom habitats from cable laying |
Introduction of hard substrate; Loss of seabed area |
Loss of habitat; Redistribution of sediments; Smothering of benthic organisms; smothering of eggs and larvae; |
|
Water quality |
Accidental spillage of contaminants or debris |
Accidental spillage of contaminants or debris |
Accidental release of contaminants |
Accidental spillage of contaminants or debris |
|
Turbidity |
N/A |
Affect primary production; secondary effects on prey species; potential smothering of eggs and larvae |
N/A |
Affect primary production; secondary effects on prey species; potential smothering of eggs and larvae |
|
Noise effects - marine mammals |
Avoidance; sound masking; stress |
Masking of sounds; displacement; temporary/permanent hearing threshold shifts; stress; injury; mortality |
Avoidance; sound masking; stress |
Avoidance; sound masking; stress |
|
Noise effects - fish |
Avoidance; sound masking; stress. |
Masking of sounds; displacement; temporary/permanent hearing threshold shifts; stress; injury; mortality; decreased catch rates. |
Avoidance; sound masking; stress. |
Avoidance; sound masking; stress. |
|
Noise effects - sea turtles |
Avoidance |
Avoidance |
Probably none |
Avoidance |
|
EMF |
N/A |
N/A |
Avoidance or attraction by sensitive species, resulting in changes to feeding or migratory behavior. |
N/A |
|
Reef effects |
N/A |
N/A |
Increased colonization for invertebrates; increased fish habitat; shelter for juvenile species; increased predators; possibility of invasive species; increased fish catch; attraction for sea turtles. |
Loss of reef effects. |
|
Vessel traffic |
Increased risk of collision with marine mammals; Increased noise causing avoidance by fish and marine mammals. |
Increased risk of collision with marine mammals; Increased noise causing avoidance by fish and marine mammals; Increased risk of collision with sea turtles. |
Increased risk of collision with marine mammals; Increased noise causing avoidance by fish and marine mammals. |
Increased risk of collision with marine mammals; Increased noise causing avoidance by fish and marine mammals. |
|
Effects to birds |
N/A |
Displacement; disturbance. |
Displacement; disturbance; avoidance; collision with turbines. |
Displacement; disturbance. |
|
Visual effects |
Increased vessel traffic. |
Increased vessel traffic, including heavy construction equipment. |
Presence of wind turbines. |
Increased vessel traffic, including heavy construction equipment. |
B. In addition to the effects caused by any
one renewable energy project within the Ocean SAMP area, the cumulative impact
of past, present, and future uses on the Ocean SAMP area must be considered.
The Ocean SAMP area is not pristine - activities in the offshore waters have
been taking place for hundreds of years - but neither is it heavily
industrialized. The ecosystem and its resources, as well as those who use the
Ocean SAMP area, are currently being directly or indirectly affected by
activities taking place inside of and beyond the Ocean SAMP area. When
considering the effects of a wind energy project on the marine environment, the
cumulative effects of existing activities such as fishing, marine
transportation, and recreation will need to be considered alongside the
proposed project, as should the effects of multiple renewable energy or other
development projects on this area. Particularly important will be the
cumulative effects of global climate change along with other current and future
activities. The total cumulative effects cannot be fully understood and cannot
be predicted with certainty, but nonetheless the potential for cumulative
effects should be taken into account. A cumulative impact analysis of a
proposed project would be required under 40 C.F.R. § 1508.7 of NEPA
regulations.
C. While not all
offshore renewable energy projects will have the same effects on the natural
resources or existing uses of the Ocean SAMP area, identifying all potential
effects aids in determining the most appropriate siting for any future
projects. Through the Ocean SAMP process existing uses and resources have been
identified and described, adding to the current understanding of the area.
Moreover, the policies and standards outlined in the Ocean SAMP document
provide protection and consideration to important areas, resources and uses of
the area. In the end, the findings and policies of the Ocean SAMP will help to
manage and address cumulative impacts of potential offshore renewable energy
development, or any future development within the waters of the Ocean SAMP
boundary.
Disclaimer: These regulations may not be the most recent version. Rhode Island may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
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