Get In Touch
The Traffic Impact Study (TIS) report should be submitted in PDF format, including SYNCHRO Level of Service (LOS) files, to the City of Walnut Creek staff. The study should be formatted in a clear and organized manner to facilitate review and decision-making. Below is the required structure of the TIS report:
Executive Summary
Introduction
Existing Conditions
Project Description
Trip Generation and Trip Distribution
Performance Measure Analysis
Near-Term (Existing Plus Approved and Pending Projects) Conditions
Near-Term Plus Proposed Project Conditions
Pedestrians/Bicycles and Transit
Site Access and Circulation
Other Analyses
Cumulative Year 2035 and Cumulative Year 2035 Plus Project Conditions
Mitigation Measures
Conclusions
Appendices
Each report must contain an executive summary that provides a concise overview of the study. This section should include:
A brief summary of the Traffic Impact Study (TIS)
Project location and size
Intersections analyzed
Study scenarios considered
Identified impacts and proposed mitigations
Key recommendations summarized in both figure and table format
The executive summary should focus on presenting key findings without including a detailed discussion of the methodologies used in the impact analysis.
This section should also document the results of the LOS analysis for intersections and other applicable performance measures for roadway segments. Additionally, it should provide a summary of site access and circulation evaluation. The executive summary should separate findings related to vehicular traffic, pedestrians, bicycles, and transit to highlight their respective impacts and considerations.
The results of the LOS analysis should be presented in a table format similar to the one below for both near-term and cumulative scenarios:
Summary of Intersection Level of Service
Intersection | Existing | Near Term (Existing Plus Approved and Pending) | Near Term Plus Proposed Project |
---|---|---|---|
Delay | LOS | Delay | LOS |
Delay | LOS | Delay | LOS |
This section introduces the purpose of the TIS, outlines the scope of work, and identifies the study area. It should summarize the objectives of the analysis, including the evaluation of transportation impacts due to the proposed project and the identification of necessary mitigation measures. Additionally, the introduction should mention any relevant City of Walnut Creek transportation policies and guidelines governing the study.
The existing conditions section should provide a comprehensive assessment of the current transportation network within the study area. This includes:
Roadway classifications and characteristics
Traffic volumes and LOS for intersections and roadway segments
Existing pedestrian and bicycle facilities
Public transit routes and ridership data
Parking availability and utilization
Any existing congestion, safety, or operational concerns
This section serves as the baseline for evaluating the impact of the proposed project on transportation infrastructure.
A detailed description of the proposed project should be included, outlining:
Project location and land use
Proposed site plan
Development phasing and timeline
Expected occupancy and operational characteristics
Any planned transportation improvements associated with the project
This section must estimate the number of trips the project will generate, distribute these trips across the transportation network, and assign them to specific roadways and intersections. Key components include:
Trip generation rates based on the Institute of Transportation Engineers (ITE) Trip Generation Manual or local data
Mode share assumptions (automobile, bicycle, pedestrian, transit)
Trip distribution and assignment methodology
Peak-hour trip estimates for AM and PM conditions
Performance measures should be analyzed using methodologies consistent with the Highway Capacity Manual (HCM) and City of Walnut Creek standards. These include:
Intersection LOS analysis
Roadway segment analysis
Queuing analysis
Multimodal performance evaluations
This section analyzes transportation conditions with the addition of approved and pending developments in the study area. It assesses how these projects will impact traffic operations, congestion levels, and multimodal infrastructure.
This analysis evaluates transportation conditions by incorporating the proposed project into the near-term scenario. The study should identify any degradation in LOS, queuing issues, or multimodal accessibility challenges due to the project.
A detailed assessment of the project’s impact on pedestrian, bicycle, and transit facilities should be included. This analysis should:
Identify existing deficiencies in pedestrian, bicycle, and transit infrastructure
Assess project-related changes in pedestrian and bicycle volumes
Analyze transit stop boardings and passenger load factors
Evaluate accessibility to transit stops and safety at pedestrian crossings
Provide recommendations to mitigate potential multimodal impacts
This section should evaluate the adequacy of site access and internal circulation for vehicles, pedestrians, and bicyclists. Components include:
Location and design of driveways, curb cuts, and access points
Internal vehicular circulation patterns
Pedestrian and bicycle pathways within the site
Sight distance analysis at access points
Compliance with City parking and loading space requirements
Signal warrant analysis (if applicable)
Any additional studies required by City staff, such as:
Emergency vehicle access analysis
Traffic calming assessments
School transportation impacts
Special event traffic management plans
This section projects long-term transportation conditions by incorporating regional growth, planned infrastructure improvements, and anticipated development trends. The analysis should consider:
Future traffic volumes based on regional forecasting models
Expected changes in LOS and congestion levels
Long-term pedestrian, bicycle, and transit infrastructure plans
If the project results in significant impacts, appropriate mitigation measures must be proposed. These may include:
Intersection improvements (signal timing adjustments, turn lane additions)
Roadway widening or reconfigurations
Bicycle and pedestrian enhancements
Transit service improvements
Transportation Demand Management (TDM) strategies
Each mitigation measure should include an estimate of its effectiveness and feasibility, along with implementation timing and potential funding sources.
This section summarizes the key findings of the TIS, restating:
Projected transportation impacts
Recommended mitigation measures
Any remaining significant impacts that cannot be mitigated
Compliance with City transportation policies
Supporting data, calculations, and supplementary materials should be included in the appendices. This may include:
Raw traffic count data
SYNCHRO analysis reports
Technical documentation of trip generation calculations
Maps and diagrams of study intersections and proposed site access
By adhering to this structured format, the TIS will provide a comprehensive and systematic evaluation of the transportation impacts associated with the proposed project, ensuring that the City of Walnut Creek has the necessary information to make informed planning and development decisions.
Our Services are available throughout City of Walnut Creek with Zipcodes 94595, 94596