17.2 Analysis Documentation

17.2.1 Reports

Reports are developed to support traffic and safety analysis assumptions, conclusions, and recommendations. Analysis reports typically include:
  • Traffic Analysis Report
    . The project traffic analysis report includes analysis assumptions and approach, data collection, analysis results, and recommendations. The traffic analysis report, at a minimum, includes content detailed in the outline in
    Appendix R, Section 1 – Traffic Analysis Report.
  • Safety Analysis Report
    . This report documents any safety analysis related to the study area, including data collection, approach, findings, and recommendations. The safety analysis report, at a minimum, includes content detailed in the outline in
    Appendix R, Section 2 – Safety Analysis Report.
  • Model Development Report.
     The model development report documents analysis performed on projects using microsimulation (microscopic) tools. The model report usually provides information on the model to review and verify accuracy when compared to real-world conditions. This report also includes assumptions, methodology, data collection, results, and any critical lessons learned and best practices to benefit future uses of the model. This report may include the calibration and validation process and consequential modifications to the base model. Changes to default values and parameters are supported by adequate justification, including supportive statistics comparing field measures and calibration parameters. The model development report, at a minimum, includes content detailed in the outline in
    Appendix N, Section 2 – Model Development Report.
     The report deliverable includes all scenario datasets, with sufficient information for TxDOT staff to replicate results. See
    Chapter 13
     for additional information on performing microsimulation (microscopic) traffic analysis. Users can coordinate with the TxDOT project manager to provide raw analysis files and data, if needed.
  • Traffic Impact Analysis (TIA) Report
    . This report introduces the existing conditions (e.g., project area, access management, existing conditions), outlines trip generation as derived from the latest version of the
    Institute of Transportation Engineers (ITE) Trip Generation Manual
    , describes the determination of trip distribution and trip assignment, summarizes future operations and LOS, and provides recommendations if mitigation measures are necessary. A recommended outline for the TIA report is found in
    Appendix Q, Section 2 – TIA Report Outline.

17.2.2 Technical Memorandums

Technical memorandums are documents that give reviewers the opportunity to examine and provide feedback on study results before they are compiled into a final report. The type and complexity of the analysis will determine the contents of the technical memorandums. Technical memorandums vary in scope but are often individual topics found in reports. It is recommended that content of the technical memorandums be reviewed and approved before proceeding to development of alternative scenarios. Technical memorandums typically include:
  • Methodology Technical Memorandum.
    This serves as a summary of the Scoping Form (introductions, project description, preliminary data review, preliminary alternative identification, analysis tool considerations, initial MOE selection, traffic forecasting, and undetermined or unresolved project scoping elements). A recommended outline for the methodology technical memorandum is available in
    Appendix B, Section 2 – Methodology Technical Memorandum.
  • Traffic Projections Methodology Technical Memorandum.
     Future year traffic projections are critical for the accurate evaluation of alternatives. This technical memorandum includes traffic projections methodology, assumptions, and recommendations. The memorandum contains a description of the historical growth rate TDM growth rate, and US census growth rates for the study area. Explanations of traffic projections for the alternatives are incorporated into the traffic projections methodology technical memorandum. Traffic projections can be approved prior to analyzing alternatives. A recommended outline for the traffic projections methodology technical memorandum is included in
    Appendix D, Section 2 – Traffic Projections Methodology Memorandum Outline.
  • Alternatives Analysis Technical Memorandum.
     This technical memorandum documents the decision-making process where multiple alternatives are evaluated and a preferred alternative is selected. It provides context for the project and discusses tier 1 evaluation, tier 2 evaluation, and preferred alternative selection. A recommended outline for the alternatives analysis technical memorandum is available in
    Appendix I, Section 1 – Alternatives Analysis Tech Memo Sample Outline.
  • Model Development Technical Memorandum.
     This technical memorandum documents the model development process, including data requirements, microsimulation network development, calibration and validation, alternatives analysis, and an appendix with raw traffic data, calibration calculations, and model outputs. A recommended outline for the model development technical memorandum is included in
    Appendix N, Section 2 – Model Development Report.
Technical memorandum deliverables can be accompanied by respective model datasets for TxDOT to replicate, as needed.