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Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU)

Fact Sheets on Highway Provisions


Year 2005 2006 2007 2008 2009
Authorization* $1,667M $1,694M $1,721M $1,749M $1,777M
*Authorizations shown here will be augmented by a portion of the Equity Bonus program funds

Program Purpose

The Congestion Mitigation and Air Quality Improvement Program (CMAQ) provides funding for projects and programs in air quality nonattainment and maintenance areas for ozone, carbon monoxide (CO), and particulate matter (PM-10, PM-2.5) which reduce transportation related emissions. [23 USC 149(a)]

Statutory References

SAFETEA-LU Section(s): 1101(a)(5), 1103(d), 1808

Other: 23 USC 149, 104(b)(2), 126(c)


Funded by contract authority, to remain available for 4 years. Funds are subject to the overall Federal-aid obligation limitation.

Funds are apportioned according to a formula based on population and severity of pollution in ozone and carbon monoxide areas, similar to the formula under TEA-21, but weighting factors have been revised. [1103(d), 104(b)(2)]

A State may transfer CMAQ funds to its Surface Transportation, National Highway System, Interstate Maintenance, Bridge, Highway Safety Improvement, and/or Recreational Trails apportionment. The amount that may be transferred may not exceed 50% of the amount by which the State's CMAQ apportionment for the fiscal year exceeds the amount the State would have been apportioned if the program had been funded at $1.35 billion annually. 23 USC 126(c)

States and MPOs will give priority in distributing funds for projects and programs to diesel retrofits and other cost-effective emission reduction activities, and cost-effective congestion mitigation activities that provide air quality benefits.

Eligible Use of Funds [1808(b)]

Eligibility is expanded to include projects and programs that:

  • establish or operate advanced truck stop electrification systems
  • improve transportation systems management and operations that mitigate congestion and improve air quality
  • involve the purchase of integrated, interoperable emergency communications equipment
  • involve the purchase of diesel retrofits that are for motor vehicles or non-road vehicles and non-road engines used in construction projects located in ozone or particulate matter non-attainment or maintenance areas and funded under 23 USC
  • conduct outreach activities that provide assistance to diesel equipment and vehicle owners and operators regarding the purchase and installation of diesel retrofits

The following States are provided the flexibility to use CMAQ funds for the activities listed:

  • Montana – operation of public transit activities that serve a non-attainment or maintenance area [1808(g)]
  • Michigan – operation and maintenance of intelligent transportation system strategies that serve a non-attainment or maintenance area [1808(h)]
  • Maine – operation of passenger rail service between Boston, MA and Portland, ME [1808(i)]
  • Oregon – operation of additional rail service between Eugene and Portland [1808(j)]
  • Missouri, Iowa, Minnesota, Wisconsin, Illinois, Indiana, and Ohio – purchase of alternative fuels (as defined in section 301 of the Energy Policy Act of 1992) or biodiesel [1808(k)]

The eligible use of program funds for States that receive the minimum apportionment is clarified to include projects that would be CMAQ-eligible if in a non-attainment or maintenance area or any project under the Surface Transportation Program. [1808(c)]

Program Features

SAFETEA-LU adds new requirement that States and MPOs will give priority to projects and programs to diesel retrofits and other cost-effective emission reduction activities, and cost-effective congestion mitigation activities that provide air quality benefits.

The EPA is to publish a list of approved diesel retrofit technologies and the emission reduction effectiveness and cost effectiveness of the technologies.

States and MPOs are encouraged to consult with State and local air quality agencies in non-attainment and maintenance areas on the estimated emission reductions from proposed congestion mitigation and air quality improvement programs and projects.

An evaluation and assessment of CMAQ projects and programs to determine the direct and indirect impact of the projects on air quality and congestion is required. A cumulative database describing the impacts shall be maintained and disseminated.

Federal Share

The Federal share is generally 80 percent, subject to sliding scale and 90 percent for Interstate projects. Certain other activities, including carpool/vanpool projects, priority control systems for emergency vehicles and transit vehicles and traffic control signalization receive a Federal share of 100 percent.

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