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CMAQ and MAP-21

CMAQ in Tennessee

State DOTs use a range of approaches to developing and implementing Congestion Mitigation and Air Quality Improvement (CMAQ) projects. TDOT selects CMAQ projects through a competitive project proposal process. TDOT develops and publishes project evaluation criteria and assigns numerical scores to each criterion. These numerical scores vary depending on the criterion. Proposals that better address each criterion are awarded higher scores.

Project sponsors (e.g., local governments or nonprofit organizations) prepare project proposals, including air emission reduction analyses, and submit them to the respective Metropolitan Planning Organization (MPO) or Transportation Planning Organization (TPO) that includes a non-attainment/maintenance county within its boundaries. The MPO/TPO submits a package of proposals from that region to TDOT. TDOT reviews, evaluates and scores the proposals that are received. Based on that review, staff recommends selected projects be funded. The Commissioner reviews those recommendations and makes the final selection of projects for funding.

All CMAQ projects must be included in a local transportation improvement program (TIP) developed by the MPO/TPO or in the statewide transportation improvement program (STIP) developed by TDOT. All CMAQ projects must also comply with National Environmental Policy Act (NEPA) requirements.

CMAQ and MAP-21

In July 2012, Congress passed the Moving Ahead for Progress in the 21st Century (MAP-21) and re-authorized the CMAQ program for federal fiscal years 2013 and 2014. While project eligibility remains basically the same, the legislation places considerable emphasis on diesel engine retrofits and other efforts that underscore a new priority on reducing fine particle pollution (PM 2.5).

Under MAP-21, states (including Tennessee) with PM 2.5 non-attainment areas must use a portion of their CMAQ funds to address PM 2.5 emissions. Eligible projects to mitigate PM 2.5 include diesel retrofits. Other project categories identified as priorities for CMAQ funding under MAP-21 include transit operating assistance and facilities serving electric or natural gas-fueled vehicles.

The CMAQ program also has new performance-based features. The Secretary of Transportation will establish measures for states to assess traffic congestion and on-road mobile source emissions. Each Metropolitan Planning Organization (MPO) with a transportation management area of more than one million in population representing a non-attainment or maintenance area is required to develop and update biennially a performance plan to achieve air quality and congestion reduction targets. In Tennessee, this will include the Nashville Area and Memphis MPOs. A CMAQ outcomes assessment study for the program is also required.

Legislative Authorizations

Jointly administered by FHWA and the Federal Transit Administration (FTA), the CMAQ program was established in 1991 as part of the Intermodal Surface Transportation Efficiency Act (ISTEA). Continuation of the program was re-authorized by the Transportation Equity Act for the 21st Century (TEA-21) in June 1998; by the Safe, Accountable, Flexible, and Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) in August 2005; and most recently by the Moving Ahead for Progress in the 21st Century Act (MAP-21) in July 2012.