A. Applicability.
1. A Traffic Impact Analysis (TIA) shall be required for projects that are anticipated to generate 100 or more peak hour vehicle trips, based on the latest edition of the Institute of Transportation Engineers (ITE) Traffic Generation Manual.
2. A Traffic Impact Analysis shall be required for projects that are anticipated to generate 1,000 or more average daily trips (ADT), based on the latest edition of the ITE Traffic General Manual.
Commentary (01/01/2021): The application of these provisions should match the type of development proposed so that excessive study scope requirements are not unreasonably imposed.
B. Scope.
1. When a traffic impact analysis is required, the
and the Town Engineer shall determine the type and scope of the study jointly during a meeting with the applicant. The
may also involve representatives of other agencies or departments. The elements to be determined during the scoping session shall include:
a. Type of Study. A letter report, full traffic impact analysis report, or special report (such as a sight distance survey) may be required.
b. Definition of Impact Area. The points of access and key streets and intersections that may be affected by of the subject tract constitute the impact area. Traffic recorder and turning movement assessment locations shall also be determined.
c. Period of Analysis. The period of analysis shall be for both the morning and afternoon peak hour.
d. Analysis Scenarios. Scenarios for analysis shall include existing conditions, and opening year with and without , and shall include increments of five years after opening until the expected completion of the project, with or without .
e. Assumptions. Trip generation and distribution assumptions including trip generation categories, diversion assumptions and distribution assumptions. Assumed rate of growth in background traffic, and developments in the area that have been approved or are under review shall also be included.
f. Duration of Study. The duration of traffic studies (the time period for which they are considered a valid basis for approvals) for large projects, particularly Planned Developments, will be evaluated on a case-by-case basis as part of the application review process.
2. Study Elements.
a. The following details shall be required as determined in the scoping meeting:
i. Existing Conditions Survey.
(a) Street System Description. The system shall be described, including geometric features, lane usage, traffic control, signage, sight distances, and adjacent uses and curb cuts.
(b) Traffic Volumes. Existing traffic volumes shall be provided for the impact area, including both average annual daily traffic (AADT) and peak hour volumes. AADT may be derived from current counts of the North Carolina Department of Transportation (NCDOT), where available, and peak hour volumes shall be provided from field counts. Data shall be adjusted for daily and seasonal variations. Turning movement counts for peak hour shall be provided for critical intersections.
(c) Capacity Analysis. Existing capacity of signalized and unsignalized intersections.
(d) Other Details. Other details may be required at the discretion of the Town Engineer or depending upon the type and scale of the project. These may include, but are not limited to, queue length analysis, pedestrian counts, accident data, traffic speeds (both 50th and 85th percentile), and stopping distances.
ii. Future without Development. Capacity analysis shall be based on the Highway Capacity Manual or other methodology approved in advance by the Town Engineer.
iii. Future with Development.
(a) Projections of peak hour traffic generation shall be made using the latest edition of the Institute of Transportation Engineers (ITE) Trip Generation Manual, unless the Town Engineer determines that locally derived data will provide more accurate forecasts. Data from similar facilities may be used where the information is not available from ITE.
(b) Special analysis may be required to determine the need for signalization, minimum safe sight distances, gap analysis, turning radius requirements, queue length analysis, turning lane length analysis, curb cut locations or similar requirements.
iv. Mitigation Plan. Where the analysis indicates that the project will create deficiencies in the impact area, improvements shall be recommended, along with projected cost estimates. The design of improvements shall be in accordance with the Town of Garner or the North Carolina Department of Transportation (NCDOT), as appropriate. Where a mitigation plan is not adequate to address the traffic impacts of the project, it may serve as a basis for denial of the rezoning, preliminary plat, site plan or Planned request.
v. Consultants. The or the Town Engineer shall require that an independent consultant be hired by the Town to perform the required studies, or to review all or part of a study prepared by the applicant's consultant. The or Town Engineer are authorized to administer the contract for any such consultant.
(a) The Town shall determine the scope of services to be performed by the independent consultant and receive a cost estimate of such services.
(b) The applicant shall provide an amount equal to the estimate to the Town, who shall deposit the amount in an escrow or other special account set up for this purpose. Any funds not used shall be returned to the applicant in a timely manner, without interest.
(c) The Town may require additional funds for independent review where a decision-making body expands the scope of the required review; the applicant substantially amends the application; additional meetings involving the consultant are requested by the applicant; or the consultant's appearance is requested at public or affected agency meetings beyond those anticipated in the original scope of services.
(Ord., 3-16-21)