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

1. Introduction

Report cover image: a parking lot of trucks, a BIKE sign, a towtruck behind a broken down car, and children getting on a school bus


Context for the Report: CMAQ History

A short history of the Congestion Mitigation Air Quality (CMAQ) Improvement Program provides an important context for this report. In 1990, Congress amended the Clean Air Act (CAA)2 to strengthen National efforts to attain the National Ambient Air Quality Standards (NAAQS). The amendments required reductions in tailpipe emissions, initiated stronger control measures in areas that failed to attain the NAAQS (nonattainment areas [NAAs]), and provided for a stronger connection between transportation and air quality planning. Shortly thereafter, in 1991, the CMAQ program was created with the Intermodal Surface Transportation Efficiency Act3 (ISTEA) in order to realign the focus of transportation planning toward a more inclusive, environmentally sensitive, and multimodal approach to addressing transportation problems.

The CMAQ program was reauthorized in the Transportation Equity Act for the 21st Century (TEA-21)4 in 1998 and again in 2005 with the Safe, Accountable Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU). Each of these subsequent bills resulted in a shift of priorities within the CMAQ program at the Federal, State, and regional levels. A provision within SAFETEA-LU established priority consideration for cost-effective emissions reduction and congestion mitigation activities. Between Fiscal Years (FYs) 2005 and 2009, CMAQ represented 4.3 percent of the Federal Highway Administration's (FHWA) total authorizations Nationwide5. In October 2008, FHWA issued Final Program Guidance ( for the CMAQ program6. The guidance notes that the CMAQ program supports two important goals of the U.S. Department of Transportation (USDOT): improving air quality and relieving congestion. In addition, the guidance provides information on project eligibility, project selection, and program administration.

Purpose of the Study

This report documents the second part of a two-phased study of the CMAQ program. The study was led by FHWA in consultation with the Federal Transit Administration (FTA) and the Environmental Protection Agency (EPA). It was undertaken in response to requirements in Section 1808(f) of SAFETEA-LU (Pub. L. 109-59, Aug. 10, 2005) to evaluate and assess the CMAQ program7. The text of this legislation is as follows:

  1. (f) EVALUATION AND ASSESSMENT OF CMAQ PROJECTS.–Section 149 of such title (as amended by subsection (e)) is amended by adding at the end the following:
    1. (1) IN GENERAL.–The Secretary, in consultation with the Administrator of the Environmental Protection Agency, shall evaluate and assess a representative sample of projects funded under the congestion mitigation and air quality program to–
      1. (A) determine the direct and indirect impact of the projects on air quality and congestion levels; and
    2. (B) ensure the effective implementation of the program
    3. (2) DATABASE.–Using appropriate assessments of projects funded under the congestion mitigation and air quality program and results from other research, the Secretary shall maintain and disseminate a cumulative database describing the impacts of the projects.
    4. (3) CONSIDERATION.–The Secretary, in consultation with the Administrator, shall consider the recommendations and findings of the report submitted to Congress under section 1110(e) of the TEA-21 (112 Stat. 144), including recommendations and findings that would improve the operation and evaluation of the congestion mitigation and air quality improvement program.

This report should be read in conjunction with SAFETEA-LU 1808: CMAQ Evaluation and Assessment: Phase I Final Report8.

Study Objectives

Phase II of the CMAQ Evaluation and Assessment Study was designed to respond to Congress's direction to ensure the effective implementation of the program. It was also designed to provide important information about CMAQ implementation to Metropolitan Planning Organizations (MPOs) and State Departments of Transportation (DOTs), which can use the information highlighted to assess and improve their programs.

Study Methodology

Phase I of the study evaluated 67 CMAQ-funded projects from the FHWA database, using emissions and cost-effectiveness data in response to the SAFETEA-LU requirement to determine the impacts of a sample of CMAQ projects. The Phase I report noted a variety of good practices that States and MPOs used to analyze and program CMAQ projects. These practices included:

Phase II of the study responds to the SAFETEA-LU requirement to ensure effective implementation of the CMAQ program. The FHWA/EPA study team, referred to as the Federal CMAQ Team throughout this report, conducted Phase II by selecting MPOs that were implementing some or all of these practices and then conducting interviews and developing case studies to document effective CMAQ project selection and implementation practices in the field. The Phase II report also provides observations from the field about challenges and opportunities for improvement in CMAQ program implementation.

The Federal CMAQ Team conducted 1-day site visits to seven locations across the country between June and September 2008. The seven locations were chosen on the basis of criteria and findings from the Phase I study. The Federal CMAQ Team identified sites that (1) had relatively high obligation rates for CMAQ funds and (2) warranted deeper analysis because they were found to have one or more of the following characteristics identified as good practices during the Phase I analysis:

In choosing the locations for site visits, the Federal CMAQ Team also considered both geographic and MPO size diversity and included some locations that had experience with diesel engine retrofit projects, since this type of project was specifically encouraged under the SAFETEA-LU legislation due to its air quality benefits. The seven sites were:

Appendix A provides more detail on the points of contact for each site visit agency, along with the locations of their regional offices of FTA, FHWA, and EPA.

The Federal CMAQ Team developed and used a standard questionnaire for all site visits. The questions and agendas were sent to the State, regional, and local representatives of each MPO prior to the visit. Site-visit participants included staff from the MPOs and State DOTs as well as representatives from one or two local CMAQ project-sponsoring agencies. Where possible, participants also included representatives from the State or regional air quality/natural resource agencies. Federal staff in attendance included representatives from FHWA Headquarters and field offices, EPA Headquarters and regional offices, FTA regional offices, and USDOT's Volpe National Transportation Systems Center (Volpe Center). The questions, which can be found in Appendix B, focused on the following areas:

The seven case studies are not intended to provide a statistically significant representation of the overall CMAQ program Nationally. Rather, they provide examples of the challenges facing agencies as they program CMAQ funds as well as examples of how agencies have effectively responded to Federal legislation and guidance as they develop methods to program and evaluate projects to meet the program's goals. The MPOs served as the main points of contact for the site visits. The term MPO is used throughout the document as opposed to region, agency, or another similar descriptor.

Report Organization

The report is organized into six major sections and three appendices:

Updated: 02/24/2012
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