Current through Register Vol. 63, No. 3, March 1, 2024
(1) All graywater. Unless otherwise approved
by the department in writing, the following requirements apply to all types of
graywater:
(a) Beneficial purposes.
(A) A person may use graywater only for the
beneficial purposes described in this rule and must divert graywater not
suitable for reuse or graywater exceeding the volume required for a beneficial
purpose to an approved sewerage system, or a functioning onsite wastewater
treatment system or holding tank system approved under OAR 340-071.
(B) A person may request an alternative
beneficial purpose not specified in this rule and must demonstrate to the
department's satisfaction that public health and the environment would be
adequately protected. The department, in a permit issued under OAR
340-053-0110(2), will include limitations or conditions or both necessary to
protect public health and the environment.
(b) Treatment. All graywater originating from
kitchen sinks must pass through primary graywater treatment.
(c) Setback distances.
(A) Except as otherwise allowed under this
rule, a person may not operate a graywater reuse and disposal system unless it
is designed and installed to meet the minimum horizontal separation distances
in Table 2.
(B) On a case-by-case
basis, the department may consider and approve in a permit issued under OAR
340-053-0110(2) a setback distance other than what is required in this rule. A
person requesting a reduced setback distance must demonstrate to the
department's satisfaction that public health and the environment would be
adequately protected.
(d) Access and exposure. The owner or
operator of a graywater reuse and disposal system must take all reasonable
steps to ensure that contact with graywater by humans and domestic pets is
avoided.
(e) Irrigation site
selection and management. The owner or operator of a graywater reuse and
disposal system may not use graywater for irrigation unless the following
requirements are satisfied:
(A) Irrigation
sites must be located on stable geologic formations that are not subject to
flooding or excessive runoff from adjacent land at the time of
irrigation.
(B) Graywater must not
be applied to areas with slopes exceeding 45 percent.
(C) Graywater must not be discharged to
frozen or saturated soils.
(D) At
the time of irrigation, the minimum separation distance between the point of
graywater discharge and the groundwater must be at least four feet.
(E) Irrigation may occur only when
evapotranspiration rates exceed natural precipitation.
(F) The soil and vegetation in the irrigation
area must have capacity to accommodate the volume and rate of graywater applied
so that discharge to surface water or groundwater does not occur.
(2) Type 1 graywater.
In addition to the requirements in section 1 of this rule, the following
requirements apply to the use of Type 1 graywater:
(a) Beneficial purposes. A person may use
Type 1 graywater only for the following beneficial purposes and only if the
rules of this division are met:
(A)
Subsurface irrigation of gardens, lawns and landscape plants;
(B) Subsurface irrigation of food crops,
except root crops or crops that have edible portions that contact
graywater;
(C) Subsurface
irrigation of vegetated roofs that do not drain to stormwater management
structures; and
(D) Subsurface
irrigation of compost.
(b) Treatment. Type 1 graywater is presumed
to contain dissolved oxygen if it has been stored 24 hours or less and does not
have an objectionable odor.
(c)
Access and exposure. A person may not use Type 1 graywater for subsurface
irrigation unless the point of graywater discharge is covered by at least two
inches of soil, mulch, compost or other suitable material.
(d) Site management. A person may use Type 1
graywater only if the following site management requirements are met:
(A) Type 1 graywater must not be stored for
more than 24 hours.
(B) When
irrigating a parcel for the production of a food crop, the edible portion of
the crop must not contact the graywater, and fruit or nuts must not be
harvested off the ground for human consumption.
(C) Graywater must not surface, pond or
runoff.
(3)
Type 2 graywater. In addition to the requirements listed in section 1 of this
rule, the following requirements apply to the use of Type 2 graywater:
(a) Beneficial purposes. A person may use
Type 2 graywater only for the following beneficial purposes and only if the
rules of this division are met:
(A) Any
beneficial purpose defined in subsection (2)(a) of this rule;
(B) Landscape ponds not intended for human
contact; and
(C) Surface drip
irrigation of gardens, lawns, living walls, greenhouses and landscape
plants.
(b) Treatment.
Type 2 graywater must meet the following secondary graywater treatment
criteria:
(A) A five-day biochemical oxygen
demand concentration of 10 mg/L or less and
(B) A total suspended solids concentration of
10 mg/L or less.
(c)
Monitoring. The owner or operator of a graywater reuse and disposal system must
monitor Type 2 graywater as follows:
(A)
Analysis of graywater quality must be made on a sample collected at a time and
from a location representative of the quality of graywater produced. Monitoring
for five-day biochemical oxygen demand and total suspended solids must occur at
the following frequencies:
(i) A system
producing 300 gallons per day or less must be sampled at least one time per
calendar year.
(ii) A system
producing greater than 300 gallons per day must be sampled at least two times
per calendar year.
(B)
The department may reduce monitoring requirements for a technology-based
graywater treatment system that satisfies the requirement of OAR
340-053-0100(2)(a) and is used as specified by the manufacturer.
(d) Access and exposure. A person
may not use Type 2 graywater unless the public is restricted from direct
contact with the graywater.
(e)
Site management practices. A person may not use Type 2 graywater unless the
following site management requirements are met:
(A) When irrigating a parcel for the
production of a food crop, the edible portion of the crop must not contact the
graywater, and fruit or nuts must not be harvested off the ground for human
consumption.
(B) When using
graywater on a parcel for a surface irrigation or a landscape pond, signs must
be posted at the use area and be visible to the public. The signs must state
graywater is used and is not safe for drinking.
(C) Unless authorized by the department in a
permit issued under OAR 340-053-0110(2), when using graywater for a landscape
pond, the pond must not combine or effect a junction with underground
waters.
(4)
Type 3 graywater. In addition to the requirements listed in section 1 of this
rule, the following requirements apply to the use of Type 3 graywater:
(a) Beneficial purposes. A person may use
Type 3 graywater for the following beneficial purposes and only if the rules of
this division are met:
(A) Any beneficial
purpose defined in subsection (3)(a) of this rule;
(B) Sprinkler irrigation of gardens, lawns,
living walls, greenhouses and landscape plants;
(C) Wash water for mechanical cleaning of
equipment, cars, sidewalks and streets;
(D) Industrial, commercial or constructions
uses limited to industrial cooling, rock crushing, aggregate washing, mixing
concrete and dust control; and
(E)
Stand-alone fire suppressions system in commercial and residential buildings,
toilet or urinal flushing, or floor drain trap priming.
(b) Treatment. Type 3 graywater must meet the
following criteria:
(A) Secondary Treatment.
Prior to disinfection, graywater must meet the secondary treatment criteria in
subsection (3)(b) of this rule.
(B)
Disinfection. After disinfection, graywater must not exceed a median of 2.2
total coliform organisms per 100 milliliters, based on results of the last
seven days that analyses have been completed, and 23 total coliform organisms
per 100 milliliters in any single sample.
(c) Monitoring. The owner or operator of a
graywater reuse and disposal system must monitor Type 3 graywater as follows:
(A) Graywater analyses must be performed on a
representative sample collected at a time and from a location representative of
the quality of graywater produced.
(B) Monitoring for secondary treatment
criteria must occur, at a minimum, at the frequency prescribed in subsection
(3)(c) of this rule.
(C) Monitoring
of a graywater disinfection system for total coliform organisms must occur
three times per week at a minimum.
(d) Setback distances. In addition to the
setback distance requirements listed in subsection (1)(c) of this rule, a
person may use Type 3 graywater for sprinkler irrigation only if the following
setback distances are followed:
(A) There
must be a minimum of 10 feet from the edge of the site used for irrigation and
the site property line.
(B)
Graywater must not be sprayed within 10 feet of an area where food is being
prepared or served, or where a drinking fountain is located.
(e) Access and exposure. A person
may use Type 3 graywater only if the following access and exposure requirements
are met:
(A) During irrigation of a public
landscape, the public must be restricted from direct contact with the
graywater.
(B) If aerosols are
generated when using graywater for an industrial, commercial or construction
purpose, the aerosols must not create a public health hazard.
(C) When using graywater for an agricultural
or horticultural purpose where sprinkler irrigation is used, or an industrial,
commercial or construction purpose, the public and personnel at the use area
must be notified that the water used is graywater and is not safe for drinking.
The operations and maintenance plan must specify how notification will be
provided.
(f) Site
management practices. A person may use Type 3 graywater only if the following
requirements are met:
(A) Irrigation of
processed food crops where the edible portion of the plant is in contact with
graywater is prohibited for three days before harvesting.
(B) When using graywater for a landscape
impoundment or for irrigating a public-accessible area such as, but not limited
to, a golf course, park, cemetery, highway median, or industrial or business
campus, signs must be posted at the use area and be visible to the public. The
signs must state graywater is used and is not safe for drinking.
(C) Unless authorized by the department in a
permit issued under OAR 340-053-0110(2), when using graywater for a landscape
pond, the pond must not combine or effect a junction with underground
waters.
(D) Aerator or decorative
fixtures that may generate aerosols from graywater are allowed only if
authorized in writing by the department.
Statutory/Other Authority: ORS
454.610,
454.625,
468.020 &
468B.010
Statutes/Other Implemented: ORS
454.610,
454.615,
468B.020
& 468B.050