Report Preparation for Transportation Impact Analysis (TIA)

1. Introduction

The Transportation Impact Analysis (TIA) is a critical component in assessing the potential impacts of proposed projects on local transportation networks. This document serves as a comprehensive guide for the preparation of the TIA report, which is essential for ensuring compliance with the California Environmental Quality Act (CEQA) and local mobility standards. The TIA must present key project details, analytical parameters, assumptions, findings, and any identified mitigation measures. Furthermore, it must be prepared under the supervision of a Professional Engineer registered with the State of California in either Traffic or Civil Engineering.

1.1 Purpose of the TIA

The primary goal of the TIA is to evaluate the potential impacts of a proposed development on the surrounding transportation system. It serves several purposes, including:

Assessing the adequacy of existing transportation facilities.
Identifying necessary improvements to mitigate any adverse impacts.
Providing data to inform decision-making by local government agencies.
Ensuring compliance with CEQA and local planning requirements.

The TIA should be well-organized, clearly communicated, and backed by relevant data and analysis.

1.2 Importance of Professional Oversight

Given the technical nature of transportation impact analyses, it is imperative that the TIA be conducted under the supervision of a qualified professional. The supervising engineer must ensure that the methodologies employed are sound and that the conclusions drawn from the analyses are reliable. This not only enhances the credibility of the TIA but also assures compliance with applicable regulations and standards.

2. Contents of the TIA Report

The TIA report should follow a structured format that encompasses all necessary components. The following outlines the essential elements that must be included in the report.

2.1 Cover Page

The cover page should contain the following information:

Project name and location.
Name and contact information of the consulting firm preparing the report.
Date of report preparation.
The stamp and signature of a registered Traffic or Civil Engineer.

2.2 Table of Contents

A table of contents should be provided to guide readers through the report. It should include all relevant sections, tables, figures, and exhibits.

3. Sections of the TIA Report

The TIA report should be organized into the following key sections:

3.1 Introduction

This section should offer a concise overview of the proposed project and its location. Additionally, it should summarize the TIA's contents, including relevant CEQA metrics and local mobility considerations. A vicinity map must be included to illustrate the project area, project site location, and any study locations essential for the Local Mobility Analysis.

3.2 Project Description

The project description must be detailed and encompass the following elements:

Location and Address: Clearly state the project site’s location and address.
Land Use Information: Describe existing and proposed land uses, including the total size for each land use and any net changes.
Access and Circulation Plan: Outline existing and proposed site access and circulation, detailing the locations of driveways and on-site loading or queuing operations.
Trip Generation Forecast: Provide estimates of trips generated by the project, considering factors such as land use type and intensity.
Trip Distribution and Assignment: Detail how trips will be distributed across the transportation network.

Exhibits for Project Description

Project Site Plan: A visual representation illustrating access points, parking areas, building footprints, and loading areas.
Trip Generation Forecast Table: A table format to present trip generation estimates.
Trip Distribution Pattern Figure: A figure that shows the percentage of inbound and outbound trips assigned to study locations by turning movement.
Trip Assignment Figure: A visual representation illustrating net new project trips assigned to study locations during peak periods (e.g., weekday AM and PM hours).

3.3 Project Context

In this section, the existing transportation network context should be thoroughly described, supplemented with photographic documentation where applicable. The following aspects must be included:

Existing Land Use: Outline existing land uses and developments in the study area, identifying commercial zones and residential neighborhoods.
Pedestrian and Bicycle Network: Describe the current state of pedestrian and bicycle infrastructure, documenting existing utilization levels and identifying any missing or substandard facilities.
Transit Network: Provide a comprehensive overview of the transit services operating within the study area, including bus routes, light rail, peak headways, stop locations, and available amenities.
Roadway Network: Detail the characteristics of the roadway network, including traffic controls, lane configurations, speed limits, on-street parking conditions, and any unique roadway features (e.g., grades, curves).
Traffic Volumes: Present current traffic volumes at study locations.

Future Conditions

The report should also address anticipated future conditions, encompassing:

Cumulative Projects: Discuss related projects and their expected impacts on trip generation, distribution, and assignment.
Growth Factors: Identify any annual ambient growth factors that may affect traffic.
Transportation Improvement Projects: List any expected improvements that will be completed before the proposed development becomes operational.

Exhibits for Project Context

Active Transportation Infrastructure Inventory: Map showing the current status of active transportation facilities.
Pedestrian, Bicycle, and Transit Destination Inventory: Map identifying key destinations served by active transportation.
Existing Bicycle and Transit Routes: Maps illustrating current routes available for cyclists and transit users.
Traffic Volume Figures: Graphical representations of existing traffic volumes at study locations.
Related Projects Figure: A figure showing the relationship of related projects to the proposed project site.
Future Baseline Traffic Volumes: Forecasted traffic volumes at study locations for future conditions.

3.4 Local Mobility Analysis

Following the project and context descriptions, the report must detail the local mobility analyses conducted. The methodology, assessment criteria, and analytical assumptions used in the analysis must be clearly stated. Summaries of results for various analysis scenarios should be included, highlighting any identified negative effects on local mobility.

If necessary, corrective measures or local improvements should be proposed, along with an assessment of their effectiveness in mitigating the project's adverse impacts. Supporting calculations, data worksheets, and other documentation must be included as attachments to the report.

Exhibits for Local Mobility Analysis

Missing or Substandard Facilities: Identify and illustrate the location and type of any deficient active transportation facilities.
Operational and Queuing Analyses Summaries: Present tables summarizing Level of Service (LOS), storage capacity, and calculated queue lengths for all analyzed scenarios.
Traffic Volume Forecast Figures: Display forecasts for “Existing with Project” and “Future with Project” traffic volumes.
Residential Cut-Through Analyses: Summarize findings regarding cut-through traffic in residential neighborhoods, if applicable.
Additional Required Exhibits: Include other exhibits necessary for the Local Mobility Analysis as per guidelines.

3.5 CEQA Analysis

If a CEQA analysis is warranted, this section should detail the evaluations performed for each CEQA transportation metric. Methodology, significance thresholds, land use assumptions, and analysis parameters should be explicitly stated. The results of the impact analysis for each metric must be presented, identifying any significant impacts. Should mitigation measures be required, their feasibility and effectiveness in reducing project impacts must be evaluated.

Supporting calculations, worksheets, and other documentation should also be provided as attachments.

Exhibits for CEQA Analysis

CEQA Analysis Summaries: Tables summarizing the outcomes of CEQA analyses, where appropriate.

3.6 CEQA Mitigation and Local Mobility Improvement Measures

This section serves to summarize local mobility findings and any identified corrective measures or improvements. If applicable, it should also summarize CEQA transportation impact findings and necessary mitigation measures that have been identified.

3.7 Summary and Conclusions

A concise summary of all pertinent data presented in the previous sections is necessary. This section should restate conclusions regarding local mobility and CEQA analyses, as well as summarize any proposed improvement or mitigation measures.

3.8 Attachments and Appendices

Attachments and appendices should be included as necessary to support the TIA report. These may comprise:

Executed Memorandum of Understanding (MOU): If applicable, include any MOUs related to the project.
Traffic Count Data: Include comprehensive traffic counts, encompassing pedestrian, bicycle, and vehicle counts.
HCM Calculation Worksheets: Provide worksheets for Highway Capacity Manual (HCM) calculations, including any micro-simulation worksheets as required.
VMT and VT Mitigation Calculators: Output worksheets summarizing Vehicle Miles Traveled (VMT) and Vehicle Trip (VT) mitigation calculations.
Bicycle and Transit Network Proximity and Quality Summaries: Present summaries of proximity and quality analyses for bicycle and transit networks.
Pedestrian Accessibility Score Summary: Provide a summary of pedestrian accessibility scores based on relevant metrics.

Other attachments may be included as needed, such as supporting documentation for empirical data, collision data, traffic signal warrant worksheets, and sight distance analysis figures.

4. GIS Shapefiles

When required, a shapefile or geodatabase should be submitted that accurately includes geolocated features related to the transportation analysis, such as an active transportation inventory map. The shapefile must be properly projected and accompanied by a layer file that applies clear and comprehensible symbology and labeling for all features.

Essential metadata should be included with the shapefile, detailing:

The name of the consultant preparing the shapefile.
The date of preparation.
Minimum attributes for each feature, including:
- Type of facility.
- Location.
- Date/time the feature was field verified.
- Name of the person responsible for verifying or creating the feature.
- Any additional notes that will assist city staff in reviewing the feature, such as the adequacy of the facility.

The Transportation Impact Analysis is an essential document that plays a critical role in evaluating the effects of new development projects on local transportation networks. Through a comprehensive and structured approach, this report should effectively convey key project details, analytical findings, and necessary mitigation measures. By adhering to the outlined guidelines, the TIA will serve as a valuable tool for city planners, engineers, and decision-makers, ultimately contributing to the development of safer, more efficient transportation systems in California.

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Report Preparation for Transportation Impact Analysis (TIA) for the project in City of Pasadena