§ 13. TRAFFIC STUDY STANDARDS AND SUBMITTAL REQUIREMENTS  


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  • A.

    Traffic Impact Studies. This section applies to any proposed site plan or subdivision plan required to submit traffic impact study and those generating 100 or more trips in the peak hour. A focused traffic study shall be required for any development that involves a drive-thru, queuing, modifications to existing access points, removing/adding access points, changing the type of traffic control at a location, or other special circumstances, unless otherwise determined by the Director. Where conflicts between this Technical Manual and the Development Code exist, the Development Code shall govern.

    B.

    Scope. The scope of the traffic impact study shall be established by the Director. Prior to beginning a traffic study, a Letter of Understanding must be drafted by the developer and agreed upon by the Director. It shall outline the study's intent, minimum scope, methodology, and any stipulations. Additional expectations of the Study may be required while it is underway, submitted, or under review. Once the Traffic Study has been accepted by the City, no further changes will be required unless the scope, size, function, or design of the project changes. The changes may be addressed through an addendum or modification of the original Study, per the discretion of the Director. No traffic study will be accepted without a Letter of Understanding.

    C.

    Submittal Requirements. Traffic impact studies should be organized as follows:

    1.

    Introduction. This would include land use, site, and study boundaries; existing and proposed site uses; existing and proposed uses in the vicinity of the site; and the existing and proposed roadways and intersections. All of these sections should have maps as appropriate.

    2.

    Existing traffic volumes. This would involve the collection of peak hour turn movement volumes at the adjacent and impacted intersections as designated by the public works department. Traffic engineering consultants should coordinate with the public works department prior to commissioning studies so that all the intersections can be identified in advance.

    3.

    Trip distribution. Develop trip distribution in conformance with the guidelines set forth in the Trip Generation Handbook and provide a figure and a verbal description of the methodology.

    4.

    Trip generation. All trip generation should be calculated using the most recent edition of ITE's Trip Generation Manual. The methodology used for the trip generation, as well as the pass-by and internal capture reductions, should conform to the guidelines set forth in ITE's Trip Generation Handbook. Maximum pass-by and internal capture reductions will conform to those set by GRTA and ARC with the DRI process. Provide justification for any trip reductions due to alternate modes. Provide a figure showing the site-generated a.m., p.m., and any other peak volumes on the same map.

    5.

    Proposed traffic volumes. Provide a figure showing the existing plus the site-generated a.m., p.m., and any other peak volumes on the same map. Include any background growth factors as appropriate. A chart and figure must be provided showing proposed traffic volumes with and without background growth rates.

    6.

    Capacity analysis. Provide existing and proposed levels of service for the roadways and intersections in the study area.

    7.

    Safety and Crash analysis (if requested). Provide historic crashes in the vicinity along with collision diagrams and summary of identified trends.

    8.

    Parking study (if applicable). Provide justification for requested parking size, typically in the form of a parking analysis, utilization, and/or accumulation study. A shared parking analysis may be required if shared parking is proposed.

    9.

    Queuing analysis (if applicable). Provide analysis showing that the proposed queues will not interfere with traffic operations or pose a safety concern.

    10.

    Recommendations. Provide a list of all proposed improvements, provide sketches, and justify whether they are project or system improvements.

    11.

    Additional items. Additional items may be required based on the type of project being analyzed, the location, surrounding land use and other considerations such as: Circulation Analysis, ADA Accessibility Analysis, Multimodal Analysis, Cut Through Traffic Analysis, Weaving Analysis, Signal Warrant Analysis, Intersection Control Evaluation, etc.

    12.

    Appendices should be provided containing all the calculations and traffic data in the formats. Appendices may be provided in electronic format only (no hard copy required) on a CD-ROM labeled appropriately for the study.

    D.

    Travel Demand Management. A Travel Demand Management Strategy shall be required of any development based on the results of the Traffic Impact Study. This may also include stipulations for continual performance monitoring and reporting.