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Congestion Mitigation and Air Quality Improvement (CMAQ) Program

The federal Congestion Mitigation and Air Quality Improvement (CMAQ) program provides dedicated federal funding to state Departments of Transportation for projects that improve air quality and reduce congestion. The CMAQ program improves air quality by funding transportation projects and programs that reduce air emissions from cars, trucks and buses (mobile sources) in air quality nonattainment and maintenance areas, which are the only areas eligible for CMAQ funding.

Areas that do not meet National Ambient Air Quality Standards (NAAQS) for selected air pollutants (carbon monoxide, ozone, and particulate matter) are called nonattainment areas. These areas are formally designated under the federal Clean Air Act by the U.S. Environmental Protection Agency (EPA) as having air pollution levels that are at times unhealthy for human beings.

When air quality in a nonattainment area improves and meets these federal air quality health standards and is no longer designated as nonattainment, it becomes a maintenance area. Maintenance areas must continue to take actions to ensure that measured air quality does not become worse and the area continues to meet federal clean air standards.

The following counties are eligible for CMAQ projects in Tennessee: Anderson, Blount, Cocke (partial county), Davidson, Hamilton, Jefferson, Knox, Loudon, Montgomery, Roane (partial county), Rutherford, Sevier, Shelby, Sumner, Williamson and Wilson.

Congress authorizes and appropriates funding for the CMAQ program, and CMAQ funds are then distributed by the Federal Highway Administration (FHWA) to state departments of transportation based on populations living in air quality nonattainment and maintenance areas. The distribution formula takes into account the severity of regional air quality problems.

Projects Eligible for CMAQ Funding

State Departments of Transportation (DOTs), local governments, and Metropolitan Planning Organizations (MPOs) may use CMAQ funds for a variety of transportation-related measures and programs. Project types typically considered eligible for CMAQ funding include:

  • Retrofit control equipment for diesel engines (e.g., diesel retrofits, engine repowers)
  • Idling reduction projects
  • Transportation control measures (TCMs) that produce air quality benefits
  • Public-private partnerships to implement projects that reduce emissions (must have a public agency sponsor)
  • Alternative fuels infrastructure
  • Traffic flow improvements
  • Transit projects
  • Bicycle and pedestrian facilities and programs (also eligible for Transportation Alternatives funding)
  • Travel demand management (TDM) programs
  • Education and outreach programs
  • Rideshare activities
  • Transit fare subsidy programs for air quality action days
  • Intermodal freight projects
  • Vehicle inspection (I/M) programs
  • Intelligent transportation systems (ITS)
  • Experimental pilot projects

Eligible highway projects include traffic flow improvements, such as traffic signal control systems, incident management programs, high-occupancy vehicle (HOV) lanes and truck climbing lanes that do not increase capacity. Projects that increase highway capacity are not eligible for CMAQ funding as they lead to increased vehicle emissions. CMAQ funds may be used for projects that reduce congestion as long as those projects achieve reductions in air emissions. Highway rehabilitation and maintenance activities are not eligible for CMAQ funding.

Match Requirements

For most projects, CMAQ funding pays a maximum of 80 percent of eligible project costs. A minimum match of 20 percent nonfederal funds is required for those projects. Project sponsors (e.g., local governments or private sector partners) are responsible for paying the 20 percent match. A small portion of CMAQ projects, such as carpool and vanpool projects, qualify for 100 percent funding.

2014 Strategic Air Quality Initiatives

For FY 2014 CMAQ funding, TDOT is focusing on several strategic air quality initiatives. A portion of this year’s CMAQ funding is being set aside for these initiatives. TDOT will hold separate competitions for project proposals and look for pilot opportunities in these strategic air quality areas.