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SAFETEA-LU 1808: CMAQ Evaluation and Assessment Phase II Final Report


  1. Executive Summary
  2. 1. Introduction
    1. Context for the Report: CMAQ History
    2. Purpose of the Study
    3. Study Objectives
    4. Study Methodology
    5. Report Organization
  3. 2. Effective Field Practices in CMAQ Implementation
    1. Transparent Project Solicitation, Prioritization, and Selection Processes
    2. Effective Practices from the Field
    3. Standardized Approaches to Project Evaluation and Ranking
    4. Effective Practices from the Field
    5. Adaptability in Response to Evaluations and Changing Conditions
    6. Effective Practices from the Field
  4. 3. Observations from the Field: Benefits, Challenges, and Opportunities
    1. Links to the Bigger Picture
    2. State DOT Involvement
    3. Air Quality Agency Involvement
    4. Data and Analysis Requirements
  5. 4. Putting it all Together: Legislation and Guidance Translate into Projects
    1. Birmingham Truck Stop-Electrification
    2. Statewide School Bus Retrofits in Massachusetts
    3. Denver's Traffic Signal System Improvement Program (TSSIP)
    4. Fort Collins Community Bicycle Library
    5. Medford, Oregon Diesel Retrofits
    6. Pittsburgh Downtown Car-Sharing Program
    7. Bay Area Freeway Service Patrol (FSP)
  6. 5. Conclusions
  7. 6. Site-Visit Case Studies
    1. Birmingham, Alabama: Regional Planning Commission of Greater Birmingham (RPCGB)
    2. Boston, Massachusetts: Boston MPO
    3. Denver, Colorado: Denver Regional Council of Governments (DRCOG)
    4. Fort Collins, Colorado: North Front Range MPO (NFRMPO)
    5. Medford, Oregon: Rogue Valley Council of Governments (RVCOG)
    6. Pittsburgh, Pennsylvania: Southwestern Pennsylvania Commission (SPC)
    7. San Francisco, California: Metropolitan Transportation Commission (MTC)
  8. Appendix A: CMAQ Phase II Site-Visit Locations and MPO Points of Contact
  9. Appendix B: CMAQ Phase II Site Visits-Interview Guide
  10. Appendix C: Acronyms and Abbreviations

List of Tables

  1. Table 1: Summary of Quantitative Measures to Evaluate CMAQ Proposals

Executive Summary

CMAQ: Strengthening National Efforts to Meet Air Quality Standards

In 1990, Congress amended the Clean Air Act (CAA) to strengthen National efforts to attain the National air quality standards. Among other strengthening provisions, the amendments required stronger coordination and linkages between transportation and air quality planning. Shortly thereafter, in 1991, Congress passed the Intermodal Surface Transportation Efficiency Act (ISTEA), which realigned the focus of transportation planning toward a more inclusive, environmentally sensitive, and multimodal approach. This included the Congestion Mitigation and Air Quality (CMAQ) Improvement Program, which was created to help fund transportation projects that reduce emissions.

CMAQ was reauthorized in the Transportation Equity Act for the 21st Century (TEA-21) in 1998, and again in 2005 with the Safe, Accountable, Flexible, Efficient Transportation Act: A Legacy for Users (SAFETEA-LU).

In 2007, in consultation with the Federal Transit Administration (FTA) and the Environmental Protection Agency (EPA), the Federal Highway Administration (FHWA) began a two-phased study as required by SAFETEA-LU Section 1808(f). Section 1808(f) calls for an evaluation and assessment of the direct and indirect impacts of CMAQ-funded projects on air quality and congestion levels to ensure the program's effective implementation.

The following report presents results from the second phase of that study and should be read in conjunction with SAFETEA-LU 1808: CMAQ Evaluation and Assessment, Phase I Final Report1. The primary objectives of the Phase II study were to:

This report highlights effective practices and identifies benefits, challenges, and opportunities encountered by agencies as they program CMAQ funds from the information collected and analyzed at these site visits. The exploration of effective practices may be useful and instructive to other MPOs and State DOTs around the country as they build their own experience with the CMAQ program and seek to improve their project implementation.

Effective Practices–Highlights

Processes for selecting, programming, and evaluating CMAQ projects varied by site location so effectiveness was broadly defined to reflect the range of circumstances observed in the field. Effectiveness was also assessed in relation to FHWA's CMAQ program guidance and results from Phase I of the study. Effective practices were identified in the three areas highlighted below.

Transparent project solicitation, prioritization, and selection processes

Two broad types of transportation planning processes were used for evaluating and selecting CMAQ projects, and good practices were found within each. The two process types were:

Standardized approaches to project evaluation and ranking

MPOs developed a variety of methodologies for project evaluation. Effective practices were found in the following areas:

Adaptability in response to evaluations and changing conditions

One success factor to developing a good CMAQ program was found to be an organization's willingness and ability to adapt and change in response to a variety of shifting factors. Those factors included evolving local conditions, new Federal guidance/legislation, and the results of project outcome evaluations. Effective practices were found in the following areas:

Benefits, Challenges, and Opportunities

The site visits also provided a better understanding of the broader planning and funding context within which transportation agencies develop CMAQ programs. MPOs reported several benefits, challenges, and opportunities related to their CMAQ program development. For example, MPOs reported that the CMAQ program improved their capabilities to:

The CMAQ program's requirements to estimate and document project benefits presented common challenges. For example, some MPOs noted that data requirements associated with CMAQ added to project costs. On the other hand, these requirements had a positive side in that they brought a higher degree of analytical rigor and justification to the planning and programming process. Other MPOs suggested that just meeting the minimum analytical requirements did not provide accurate estimates of emissions reductions over the life of the project. Still others noted that it was a challenge to allocate the staff time required for administering CMAQ to a funding source that represents a small portion of their overall transportation budgets.

Many agencies agreed that CMAQ's additional requirements can be seen as positive at a broad level and as a model for using analysis to identify projects with clearly defined and measurable benefits.


While the CMAQ program is Federally funded, no National standard or set of regulations exists for how a CMAQ program should be structured and operated at the State or MPO level. It is intentionally left to the State or MPO to develop a process and operate a program that best responds to local or regional needs. Reflecting this, the Federal CMAQ Team found differences in structure and operations at every one of the seven sites visited.

The agencies interviewed for this study represent a very small sample of CMAQ programs across the country but allowed the Federal CMAQ Team to draw several conclusions about potential effective practices as well as benefits, challenges, and opportunities presented by the CMAQ program. These are:

To demonstrate by specific examples the range and variety of CMAQ projects that have arisen from the legislation and guidance, this report includes seven brief summaries of CMAQ-funded projects. The summaries highlight projects that the MPOs interviewed felt were successful in areas such as providing air quality benefits, strengthening interagency cooperation, increasing economic vitality, improving quality of life, and leveraging funds to maximize impact across geographic boundaries. The summaries will help readers to gain insight into the benefits, challenges, and opportunities reported by agencies involved with CMAQ project selection and evaluation.

Updated: 3/17/2015
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