Traffic impact studies are required to enable the Township to
identify the potential impacts of a proposed development and determine
the roadway improvements necessary to mitigate any impacts resulting
from the development.
A traffic impact study shall be submitted for any development
which meets the following criteria: residential, 50 or more dwelling
units; nonresidential, 20,000 square feet or more of total floor area;
or any use that generates 750 or more trips per day. In all cases,
a traffic impact study will be conducted when, in the opinion of the
Planning Commission/Township, the site development is expected to
have a significant impact on the safety and/or traffic flow of the
affected roadway(s).
The study shall be conducted by a professional engineer in the
Commonwealth of Pennsylvania that has verifiable experience in the
study of traffic engineering. The study shall be prepared in accordance
with the Institute of Transportation Engineer's Recommended Practice
Traffic Access and Impact Studies of Site Development, current edition,
and PennDOT Publications 201 and 282, current edition, and the requirements
contained herein. The full cost of completing the study and of a review
by the Township representative shall be borne by the applicant.
Study area boundaries shall be determined in accordance with
the preceding publications and through discussion with the Township
Planning Commission and Township Engineer. When establishing the study
area boundaries, sufficient area shall be included to ensure that
any corridors that afford access to the site and critical intersections
that may be affected by the site generated traffic are taken into
account. The study area will generally include the adjacent major
intersection plus the first signalized intersection.
A traffic study prepared in accordance with the preceding publications
and shall include the following sections:
A. Site description. This section should contain a brief description
of the size, location, existing and proposed land uses, current zoning,
construction phasing and completion date of the proposed development.
A brief description of other major existing and proposed land development
within the study area shall be provided.
B. Existing and Proposed Roadways And Intersections. Within the study
area, describe existing roadways and intersections (geometrics and
traffic signal control) as well as improvements proposed by government
agencies. Describe the proposed internal transportation system for
this development including ingress and egress locations, existing
or proposed internal roadways, parking conditions, traffic channelization
and any other traffic control devices within the site.
C. Existing Traffic Conditions. This section describes the existing
traffic conditions analysis to be completed for the roadways and intersections
in the study area.
(1)
Provide daily and peak hour(s) traffic volumes for roadways
within the study area. Turning movement and mainline volumes are to
be presented for the a.m. and p.m. peak hours and any site generated
peak hours. Traffic volumes should be based on actual counts conducted
within the prior two years.
(2)
Utilizing methodology described in the Highway Capacity Manual,
current edition, include a volume/capacity analysis of the existing
volumes during the peak hours for all roadways and intersections.
Levels of service (A through F) are to be computed and presented for
key traffic movements, including turning movements. Traffic signal
warrant analysis shall be conducted for all unsignalized intersections
in accordance with PennDOT Publication 201. Gap studies and queue
length analysis shall also be completed for the key intersections.
The analysis of the existing road network will be based on the current
geometric condition and traffic condition.
D. Analysis of Future Conditions Without Development. The analysis of
the future conditions without the proposed development will document
the adequacy of the study area network to accommodate the traffic
in the design year(s) without the proposed development. This analysis
must include a full consideration of all committed roadway improvements
to the study area network. Clearly indicate the method and assumptions
used to forecast future traffic volumes. Perform volume/capacity and
associated analyses.
E. Trip Generation. The study shall include an estimate of the number
of trips expected to be generated by the use during the a.m., p.m.
and site-generated peak hours. Such estimates shall be based on the
latest published estimates of the Institute of Transportation Engineers,
unless the applicant provides the Township with estimates and supporting
documentation based upon actual counts at similar developments. These
generated volumes shall be distributed to the study area and assigned
to the existing roadway at key intersections throughout the study
area.
F. Analysis of Future Conditions With Development. Perform a volume/capacity
analysis for the appropriate peak hours for future conditions with
the site development as proposed. As a result of the volume/capacity
analysis, compute and describe the level of service on the study area
roadway system. Final design must address both traffic flow and traffic
safety considerations to provide safe operational characteristics.
G. Recommended Improvements. Detail necessary improvements to the study
area roadway network which will provide for a level of service for
the design year(s) with the development which is at least equivalent
to the projected level of service for the design year(s) without the
proposed development. Describe the location, nature and extent of
proposed improvements to assure sufficient roadway capacity. Perform
volume/capacity analysis, which demonstrates the anticipated results
of making these improvements. As a result of the revised volume/capacity
analysis presented in the previous section, present levels of service
for the highway system with improvements. For each recommended improvement,
provide a preliminary cost estimate, source of funding, and the implementation
schedule for the improvement. Where new intersections are being established
to serve as access to the proposed development, these intersections
must be designed to at least operate at Level of Service D or better.
H. Final Report. A final report must be prepared to document the results
of the traffic study and the recommended improvements to accommodate
the projected traffic due to the proposed development. Provide an
executive summary, which provides a concise description of the study
area, result of the traffic analysis and any recommended improvements.
The presentation of data and analyses results should be accomplished
on schematic diagrams of the study area and the use of charts and/or
tables. All sources of data and methodologies that were used in the
study must be properly reference and documented. Provide all computer
output and calculations in appendices.
I. Completion of Improvements. Any traffic improvements that are required
as a condition for any approval shall be in place of sufficient funds
committed in escrow acceptable to the Township prior to the issuance
of any needed occupancy permit, or within a staged process agreed
to at the time of approval.