New Jersey Administrative Code
Title 16 - TRANSPORTATION
Chapter 47 - STATE HIGHWAY ACCESS MANAGEMENT CODE
Appendix F - TRAFFIC IMPACT STUDIES
A traffic impact study is required for all major with planning review access applications, and may be required, at the Department's discretion, for major access applications. The purpose of this study is to identify and analyze the impact of all traffic being generated by a lot or site utilizing the State highway, regardless of how the traffic accesses the State highway system. The study shall be completed and sealed by a New Jersey licensed professional engineer and follow the proscribed format:
F-1 Traffic Impact Study Report
The following report outline describes all topics that shall be addressed in the Traffic Impact Study Report. The report shall present the information in the sequence outlined below and all pages shall be numbered.
F-1.1 Executive Summary
The summary shall include a synopsis of each of the sections that follow. This summary shall also include the following:
a. A statement that the Level of Service (LOS) standards set forth in F-1.8 of this appendix are met. If they are not met, the summary shall include a description of the lot or site owner's proposal for achieving those standards either through construction of improvements to the State highway system or any proposed means of meeting the fair share obligation.
b. Any improvements not required by these rules, but desired by the lot or site owner, should be presented along with facts supporting their feasibility and a statement indicating that the lot or site owner will have full financial responsibility for their implementation.
c. A description of all instances where proposed access is not in conformance with the provisions of this chapter, a brief description why, and confirmation that a waiver request will accompany the application.
F-1.2 Development Description
The development description shall identify the lot or site owner and development name and shall include a location map. It shall provide a description of the development based on sizes and land use types that are comparable with those land uses listed in the ITE publication entitled "Trip Generation Manual, 10th Edition," or superseding edition or other uses provided by the Department on its website for trip generation rates found at http://www.state.nj.us/transportation/business/accessmgt/. For land uses not listed in these sources or when a lot or site owner believes these uses are not representative of his or her development type, the Department may accept alternative evidence of appropriate land uses. The Department has adopted its own definitions for some land uses that differ from those found in the ITE trip generation manual.
The development description shall also identify unique functional or operational activities occurring on the lot or site that may affect trip generation from the lot or site, such as ridesharing participation, bus intercept areas, or recreational use facilities. It shall describe, as appropriate, the development staging plan identifying the sequence of development activities, timing of staged developed and proposed access plans for each stage of development, and all existing or proposed easements for shared driveways for the development.
F-1.3 Pre-Application Meeting Summary
Issues raised at the pre-application meeting shall be presented and their resolution addressed in summary form.
F-1.4 Scope of Study
To satisfactorily delineate the traffic impact study area, all trips being generated by a lot or site and utilizing the State highway, regardless of how the traffic accesses the State highway system, must be considered. The following information shall be used to delineate the traffic impact study area:
a. Trip Generation
The ITE publication entitled "Trip Generation Manual, 10th Edition," or superseding edition, or superseding rates Amended by the Department, shall be used to calculate trip generation. Department trip generation rates shall govern over ITE rates. The ITE publication is available at http://www.ite.org/bookstore/index.asp. The Department's approved trip generation rates are available on the Department's website at: http://www.state.nj.us/transportation/business/accessmgt/ or from any Department offices found at N.J.A.C. 16:47-9.5(g). Trip generation tables shall be provided in summary form for A.M. weekday peak hour, P.M. weekday peak hour, weekend peak hour, weekday daily, and weekend daily traffic volumes for each land use on the lot or site. The tables should identify size, type, and appropriate ITE or Department land use code used to establish these traffic volumes.
For land uses not listed in these sources or when a lot or site owner believes these traffic volumes are not representative of his or her proposed development, the Department may accept alternative evidence of representative traffic volumes. The lot or site owner must seek prior approval from the Department to request a waiver for alternate methods for calculating trip generation. The request for a waiver must include documentation for site-specific locations, describe the land use in detail, and provide supporting documentation. Any credit or reductions for pass-by trips or mixed-use developments shall follow the methodology outlined in the ITE "Trip Generation Manual, 10th Edition, Volume 1: User's Guide and Handbook." See N.J.A.C. 16:47 Appendix E for details on availability.
b. Trip Distribution
The procedure and rationale used to establish trip distribution from the proposed lot or site shall be documented. Trip tables for each land use on the lot or site shall be shown. The documentation shall tie the trip table to the data source, such as U.S. Census "Commuting in the United States: 2009," marketing studies, gravity model, or employment data. Where existing travel patterns or other information are used for all or a component of the lot or site's traffic, an explanation is required as to why the expected patterns are likely to replicate these existing patterns. Trip distribution shall be described and illustrated by figures.
c. Trip Assignment
Trip assignment shall follow logically from the trip distribution established above. Any special deviations from this logical assignment shall be explained. Peak hour traffic volumes covering the analysis area shall be illustrated by figures and must identify lot or site generated trips broken into primary, pass-by, diverted link, and total traffic. Traffic entering and exiting the lot or site shall be routed on public roadways, the subject lot or site, or another lot or site by a permanent easement. The distribution of these trips must be discussed and the impact of any additional trips on an existing lot or site's permit addressed.
d. Determination of Study Locations
1. Study locations shall be based on trips generated to and from the lot or site and their origin and destination and illustrated by figures.
2. The lot or site owner's responsibility for all trips to and from the lot or site and either their origin or destination ceases at the midpoint of each trip. The half of each trip furthest from the lot or site shall be eliminated. This determination shall be made based on a trip table that identifies origins and destinations. Documentation must be provided that clearly illustrates the midpoint for each trip and what method was utilized to derive that location.
3. Study locations include all locations with 100 or more new half-trips during any peak hour. These locations may include:
i. The lot or site driveway, whether signalized or not;
ii. The lot or site non-State highway access, whether signalized or not;
iii. All signalized driveways within the traffic impact study area; and
iv. All intersections, whether signalized or not, uninterrupted flow highway sections, highway weaving sections, highway merge sections, and highway diverge sections.
4. Unsignalized driveways, other than the lot or site owner's driveways, shall not be considered traffic impact study area locations.
F-1.5 Transportation System Inventory
a. The transportation system inventory shall describe the physical, functional, and operational characteristics of the roadway system in the traffic impact study area. Transportation system inventory data shall include, where applicable, the following:
1. Highway peak hour volumes;
2. Highway cross- section;
3. Traffic signals and configuration, including existing timing;
4. Traffic signal progression;
5. Percentage of heavy trucks;
6. Grades;
7. Jurisdictional responsibility for each road;
8. Transit routes, stops, and frequency;
9. Sidewalks and bikeways; and
10. A discussion of the interaction of conflicting movements at adjacent driveways or streets.
b. Traffic signal configurations, timing, and signal progression information can be obtained from:
Bureau of Traffic Engineering
New Jersey Department of Transportation
1035 Parkway Avenue
PO Box 600
Trenton, NJ 08625-0600
609-530-2600
F-1.6 Traffic Signal Progression Analysis
A traffic signal progression analysis, as described in NJ.A.C. 16:47 Appendix G, will be required when the minimum signal spacing requirements found at Table G-1 are violated, or a new traffic signal is proposed within an existing coordinated traffic signal system, or if changes to phasing/timing of existing signals are proposed without adding a new traffic signal.
F-1.7 Traffic Analysis
a. Traffic Counts
Traffic counts shall be taken in a manner that establishes average annual daily traffic and daily peak hours and shall be taken within 12 months of the application date. Traffic counts shall be shown by 15-minute intervals over a period long enough to establish a peak hour, generally a two-hour period. Traffic counts shall be taken for all traffic impact study area locations or, if available, obtained from the Department. Traffic counts shall not be taken when conditions, such as detours, school closings, road construction, accidents, or inclement weather exist. Traffic counts shall not be taken on or near holidays or other special events when traffic volumes may not be representative of average daily traffic. Traffic counts performed outside the seasonal peak period in tourist or recreational areas shall be adjusted to the peak period. Counts found not to be representative will not be accepted by the Department.
Vehicle classification and manual turning movement counts for one day shall be supported by one week of machine counts. To be acceptable, a manual count must be within 10 percent of the machine count on each approach that day, considering the total for the manual counting period. Weekday peak hour manual counts shall be factored to agree with the weekday machine count for the highest hour of the week. Weekend manual counts, if within 10 percent of the machine counts, need not be factored, but shall encompass the machine peak hour for the day. The number of two-way, all lane machine counters shall be no less than the number of signalized intersections to be counted, unless otherwise waived by the Department. Generally, the counters shall be placed to cordon the State highway limits of the traffic impact study area. All counts shall be included in the traffic impact study as an appendix. The Department may require evidence of proper calibration of automatic traffic recorder (ATR) equipment.
Vehicle classification must be sufficient to address the needs of the LOS analysis; however, where large percentages of multi-axle vehicles are present it may be necessary to more finely stratify the classification in order to conform to the machine count.
At or after a pre-application meeting, the Department may approve alternative proposals for counting programs, as long as they conform to the intent of this section.
b. Highway Traffic Volumes
The highway traffic volumes shall represent the traffic volumes anticipated on the date that the driveway is to open. To establish these volumes, it is necessary to identify the analysis year to be included in the study, which is the build year or other years, as may be appropriate, due to development staging or programmed highway improvements. The traffic volume shall include the traffic counts taken within the traffic impact study area to which background traffic growth rates have been applied when applicable. The background traffic growth rate is the rate at which traffic volumes are projected to increase over a period of time, expressed as a percentage that is compounded annually. The Department publishes background traffic growth rates, covering the entire State, which must be used for this analysis. The Department updates these rates every two years. Traffic from anticipated major traffic generators located on the State highway system and within the traffic impact study area shall be added to the background traffic data. Anticipated major traffic generators are existing development (vacant, inactive, or not open for business); developments that have a permit and were under construction at the time traffic counts were taken, but not yet opened; or development for which permits have been issued, but construction has not yet begun. The logic and calculations used to establish the highway traffic volumes presented in the traffic analysis shall be provided for review and acceptance by the Department. Each stage of the development of the traffic volumes shall be illustrated by figures.
c. Analysis of Study Locations
For each study location, the analysis shall identify the configuration; traffic volumes; all the variables that pertain to that type of study location including, but not limited to, turn slots, jughandles, and the queues, merges, and diverges associated with those features; travel speeds; and the delays that affect the LOS. The analysis shall be performed for each peak hour at each driveway or street for the lot or site and the study locations established pursuant to F-1.4d and using the standards found at F-1.8 of this appendix. The analysis should include: existing conditions; the no-build condition (impacts for the build year without the development traffic); the build condition (impacts for the build year with development traffic and without any proposed transportation improvements); and the build with mitigation condition (impacts for the build year with development traffic and with proposed transportation improvements). Improvements to be made by others cannot be considered as existing unless they are advertised for construction or awarded as appropriate, or, in the case of other developments, they have a valid executed permit at the time of application. For staged developments, the existing condition needs to be established only once. For each stage of development, the analysis should include the no-build, build, and build with mitigation evaluation.
The build and build with mitigation analysis for each stage of development will utilize the appropriate increased background traffic growth and the associated cumulative development traffic for that stage. The no-build analyses for each stage will not include any traffic or improvements from earlier stages of the development.
The peak hour traffic analysis must identify lot, site, State highway or street, other factors affecting the peak hour condition, and the beginning and end of the peak hour used. The peak hours analyzed will be the A.M. and P.M. weekday peak hours and the weekend peak hour and shall reflect the combination of lot or site and highway traffic that causes the most critical impacts during those periods.
When analyzing a lot or site's driveway, trip generation as determined by the ITE publication entitled "Trip Generation Manual," 10th Edition, or superseding edition, or superseding rates Amended by the Department shall be used, not the actual traffic counts for that driveway.
The Transportation Research Board's Highway Capacity Manual (HCM) is the standard for LOS analysis. The use of other procedures must be justified and documented and approved by the Department at the pre-application meeting (see N.J.A.C. 16:47-9.4). Work sheets must be provided as an appendix to the traffic impact study. Any deviation from the default values contained in the HCM shall be fully documented. Default values shall not be used when field observation indicates that they are not appropriate. Values shall be the same for the no-build and build analysis. If values are changed without justification, the Department may reject the traffic impact study. For signalized locations, the same signal timing should be used for the no-build and build without improvements.
As appropriate to the type of analysis, the study shall include summary tables that show volume, number of lanes, green time, volume to capacity ratio (V/C ratio), delay, and LOS for each lane group or movement on each approach. V/C ratio means a ratio used to measure roadway travel performance that is calculated by dividing the number of vehicles passing a given point on a State highway or street during a time interval by the theoretical capacity of the roadway at that same point for the same unit of time. Detailed printouts of the current version of the HCM software, or other comparable software as approved by the Department, for each analysis shall be included in the study.
F-1.8 Level of Service Analysis Standards
a. Introduction
LOS analysis standards are based on the current version of the HCM and shall be used to establish whether or not an LOS violation occurs by comparing the no-build condition to the build condition. If a violation occurs in the build condition, mitigation will be required.
b. Signalized Intersection Standards
LOS will be measured by control delay per vehicle, as shown in the tables contained in the HCM.
1. Urban State highway segments: For all movements at study locations on State highway segments designated urban and operating at LOS A, B, C, D, or E under the no-build condition: in the build condition, each movement may deteriorate by 25 percent of the difference in delay between the LOS in the no-build condition and the bottom of LOS E without violating the Department's LOS standards. If a traffic movement on any approach operates at LOS F in the no-build condition, no delay deterioration will be allowed for that movement. The delay deterioration for LOS F shall be expressed as the V/C ratio for that movement.
2. Rural State highway segments: For all movements at study locations on State highway segments designated rural and operating at LOS A, B, C, or D under the no-build condition: in the build condition, each movement may deteriorate by 25 percent of the difference in delay between the LOS in the no-build condition and the bottom of LOS D without violating the Department's LOS standards. If a traffic movement on any approach operates at LOS E or LOS F in the no-build condition, no delay deterioration will be allowed for that movement. The delay deterioration for LOS F shall be expressed as the V/C ratio for that movement.
3. New approach: If a new approach is added to an existing signalized intersection, all movements of the new approach shall operate at a minimum of LOS C based on the build year traffic volumes. All proposed new signalized intersections shall operate at a minimum of LOS C for all movements.
c. Unsignalized Intersection Standards
LOS will be measured by average control delay as shown in the tables contained in the HCM. The unsignalized intersection analysis shall be based on the LOS, delay and traffic volume at the peak hour.
1. Street intersections: For a study location at street intersections, the maximum allowable build delay for each movement shall be determined as follows:
i. Urban State highway segments: For all movements at study locations on State highway segments designated urban operating at LOS A, B, C, D, or E under the no-build condition, in the build condition each movement may deteriorate by 25 percent of the difference in delay between the LOS in the no-build condition and the bottom of LOS E without violation. If a traffic movement on any approach operates at LOS F in no-build condition, no delay deterioration will be allowed for that movement.
ii. Rural State highway segments: For all movements at study locations on State highway segments designated rural operating at LOS A, B, C, or D under the no-build condition, in the build condition each movement may deteriorate by 25 percent of the difference in delay between the LOS in the no-build condition and the bottom of LOS D without violation. If a traffic movement on any approach operates at LOS E or F in the no-build condition, no delay deterioration will be allowed for that movement.
2. Driveways: For a study location at a driveway the LOS for each movement shall be determined as follows:
i. Urban State highway segments: All movements to and from driveways shall operate at a LOS E or better in the full build condition.
ii. Rural State highway segments: All movements to and from driveways shall operate at a LOS D or better in the full build condition.
d. Uninterrupted Flow Standards
LOS will be measured by the V/C ratio and conform to the values shown in the tables contained in the HCM.
1. Urban State highway segments: For study locations applicable to a State highway segment designated as urban and anticipated under the no-build condition to operate at:
i. LOS A or B, an increase in the uninterrupted flow V/C ratio to the midpoint of LOS C will be allowed;
ii. LOS C, D, or E, an increase in the uninterrupted flow V/C ratio of 0.1 will be allowed, provided that the LOS does not drop below LOS E; or
iii. LOS F, no increase in the uninterrupted flow V/C ratio will be allowed.
2. Rural State highway segments: For study locations applicable to a State highway segment designated as rural and anticipated under the no-build condition to operate at:
i. LOS A or B, an increase in the uninterrupted flow V/C ratio to the midpoint of C will be allowed;
ii. LOS C or D; an increase in the uninterrupted flow V/C ratio of 0.1 will be allowed, provided that the LOS does not drop below LOS D; or
iii. LOS E or F, no increase in the uninterrupted flow V/C ratio will be allowed.
e. Weaving Area Standards
LOS will be measured by weaving speed and non-weaving speed and shall conform with the values shown in the LOS Criteria for Weaving Sections as found in the current edition of the HCM. LOS shall not deteriorate below a LOS E in the full build condition.
f. Ramp Standards
Ramp standards are based on density, the primary measure of effectiveness, and the LOS criteria shown in tables contained in the current edition of the HCM.
1. For study locations, applicable to either urban or rural State highway segments, and with:
i. A merge or diverge influence area that operates at LOS A, B, C, or D under the no-build condition, the maximum allowable deterioration shall be 25 percent of the difference between no-build density and 35 passenger cars per mile per lane (the maximum density allowed under LOS D); or
ii. A merge or diverge influence area which operates at LOS E or F under the no-build condition, no deterioration will be allowed.
F-1.9 Level of Service Violation Component
A traffic impact study shall provide a written summary of all LOS violations identified in F-1.7, Traffic Analysis, which will be addressed in F-2, Mitigation of Traffic Impacts. LOS violations should be described in terms of the number of vehicles that create the LOS violation in the build without mitigation condition for a particular movement or lane group (LOS violation component) and the number of vehicles that can make the particular movement without an LOS violation occurring (acceptable component) and is determined as follows: The volume for a movement or lane group that is in violation during the build without mitigation condition will each be reduced until a violation no longer occurs for that lane group or movement. The reduced volume will then be subtracted from the total traffic for the movement or lane group in the build without mitigation condition to determine the LOS violation component for that movement or lane group. This process will be repeated for each lane group or movement in violation in the build without mitigation condition. Each LOS violation component will be added together to determine the total LOS violation component for the study location.
F-2 Mitigation of Traffic Impacts
F-2.1 Mitigation
a. When the analysis of the study locations identifies a LOS violation, capacity improvements that mitigate that violation must be identified in a written summary. Mitigation at each location shall add capacity sufficient to accommodate the anticipated increase in traffic between build and no-build conditions at the time the access opens, without violation of the LOS standards. These improvements may include, but are not limited to, roadway and structure widenings, frontage roads, intersection improvements, structures, reverse frontage roads, auxiliary lanes, and alternative access.
b. The proposed mitigation may not be limited to the specific location where an unacceptable deterioration of the LOS standard has been identified. Improvements apart from the violation site may divert enough background traffic to provide capacity for the lot or site-generated traffic and, thus, mitigate the impacts.
c. Mitigation shall be compatible with, but shall not exceed, the desirable typical section for the State highway segment as shown in N.J.A.C. 16:47 Appendix B-2.
d. Mitigation shall be based on the conditions that exist at the time the application is submitted to the Department. Improvements to be made by others cannot be considered as existing unless they are advertised for construction or under construction, another arrangement has been made to ensure the improvements will be in place, or, in the case of other developments, they have a valid executed permit at the time of application.
e. In either urban or rural areas where a violation occurs at a signalized study location, if a traffic movement on any approach operates at a LOS F in the no-build condition, the proposed mitigation must, at a minimum, correct that violation back to the V/C ratio in the no-build condition.
f. The Department shall consider the needs of the lot or site owner and the public in determining the location or type of State highway improvements.
g. If a lot or site falls within the boundaries of a designated Transportation Development District or other transportation improvement cost sharing plan in which the Department is a participating member and the development is subject to a fee assessment as part of the plan, then the Department will only require mitigation for improvements to the State highway system outside of the Transportation Development District boundaries.
F-2.2 Mitigation Obligation
a. For each peak hour, and at all locations where a traffic analysis identifies an LOS violation, a lot or site owner shall have an obligation to propose mitigation that will correct the violation. Where mitigation is proposed, the lot or site owner shall have an obligation to provide for his or her fair share of that mitigation. The lot or site owner's fair share obligation may be satisfied in the form of constructing capacity improvements to the State highway system, or when deemed appropriate by the Department, by providing a non-refundable financial contribution. Fair share obligations may include right-of-way dedications. The value of the dedicated lands will be determined by the Department, based on their fair market value.
b. When more than one location requires mitigation, the Department and the lot or site owner may agree to consolidate the fair share obligations to provide improvements at one or more targeted locations.
c. Lot or site owners shall be 100 percent responsible for mitigation required to provide access across the lot or site frontage to the State highway or to correct LOS violations at adjacent State highway intersections, which serve their non-State highway access to their lot or site. This includes any right-of-way dedications for these improvements.
d. If the development is staged, fair share obligations may be staged, as long as the fair share obligation for each stage is fulfilled in advance of that particular stage.
F-2.3 Fair share obligation determination
a. At locations where a traffic analysis has identified a, LOS violation, the capacity of the intersection where the LOS violation occurs must be determined for both the no-build and build with mitigation conditions. In determining the fair share obligation, "capacity" means the maximum traffic volume possible at the bottom of LOS E in urban areas and at the bottom of LOS D in rural areas expressed as number of vehicles. When more than one measure of LOS is possible at a study location, such as the various movements at an intersection, then the most sensitive measure shall determine the capacity. Capacity is determined as follows: Traffic volumes for all movements shall be factored by a constant, so that all movements will remain a fixed percentage of the total volume at the study location, until the maximum attainable volume is achieved without the capacity of any movement being exceeded. The sum of the traffic volumes of all movements is the capacity for that study location. At signalized intersections where the LOS of each movement is not a direct function of the traffic volume of another movement, each lane group may be factored independently to determine its capacity, and the lane group capacities are added to determine the capacity of the entire intersection. The analysis of capacity of study locations shall follow the same guidelines provided in F-1.9, Level of Service Violation Component.
b. The values used to determine the capacity shall be the same as the values used in the analysis of the study locations. No changes to the values will be allowed without prior substantiation and approval by the Department.
c. The lot or site owner's fair share obligation for mitigation, other than that described in paragraph b above, shall be determined as follows:
1. Lot or site traffic is comprised of the LOS violation component and the acceptable component. The LOS violation component is comprised of those lot or site generated trips, which violate the LOS standards at each study location analyzed. The acceptable component is comprised of those lot or site generated trips that do not violate the LOS standards:
Lot or Site Traffic = LOS Violation Component + Acceptable Component
2. The capacity increase created by mitigation shall be equal to the capacity after mitigation minus the capacity before mitigation:
Capacity Increase = Capacity After Mitigation - Capacity Before Mitigation
3. The fair share proportion at a location shall be equal to the LOS violation component divided by the capacity increase, as reflected in the following formula:
Fair Share Proportion = LOS Violation Component / Capacity Increase
Both LOS Violation Component and Capacity Increase shall be expressed as number of vehicles.
d. The cost of mitigation at a location shall be the estimated costs for the Department to provide the mitigation at the build year for the development. This includes, but may not be limited to, all of the following:
1. Design of mitigation;
2. ROW appraisal and acquisition;
3. Utility relocations;
4. Construction of the mitigation;
5. Management of the construction; and
6. Environmental cleanup, permits, and mitigation.
e. The fair share obligation at a location shall be equal to the fair share proportion multiplied by the cost of the mitigation, as reflected in the following formula:
Fair Share Obligation = Fair Share Proportion x Mitigation Cost
f. If the application qualifies for reduced fees as set forth in N.J.A.C. 16:47-9.8(b), then the total fair share for the residential component of the lot or site shall be reduced by the same proportion of the total daily trip generation of the low- and moderate-income units to the total daily trip generation of the lot or site.
