Transportation Improvement Program - Air Quality Conformity

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Air pollution doesn’t just come from factories and power plants—our transportation system contributes a sizable amount, as well. Cars, trucks, buses, trains, ships, maintenance vehicles, and construction equipment all emit pollution into the atmosphere.

The MPO works closely with member municipalities and the Massachusetts Department of Environmental Protection (MassDEP) to address air quality issues related to transportation. Read on to learn more about how we’re doing our part to clean up our region’s air.

Air Quality Conformity Determination

The MPO routinely performs air quality conformity determinations before it endorses a Long-Range Transportation Plan or Transportation Improvement Program, and at other times, as required by state and federal regulations under the Clean Air Act Amendments of 1990 (CAAA). Air quality conformity determinations are required of all metropolitan planning organizations within nonattainment areas—regions that the United States EPA has designated as not meeting certain air quality standards.

Annually, MassDEP reviews all of the MPO’s plans, programs, and projects for consistency with the State Implementation Plan (SIP) for meeting federal air quality standards—as required under both federal (40 CFR Part 93) and Massachusetts (310 CMR 60.03) regulations. The result: a conformity determination that demonstrates that federal funds are going only to those transportation activities that are consistent with air quality goals under the CAAA.

For a detailed discussion of air quality and the Transportation Improvement Program, see Chapter 4 of the TIP—Determination of Air Quality Conformity.

Congestion Mitigation and Air Quality (CMAQ) Improvement Program

The MPO’s Congestion Mitigation and Air Quality (CMAQ) Improvement Program funds transportation projects or programs in the TIP that will contribute to attaining or maintaining national ambient air quality standards for ozone, carbon monoxide, and particulate matter. The CMAQ program supports two important goals: 1) improve air quality, and 2) relieve congestion. The Boston Region MPO aims to dedicate approximately $8 million each year to CMAQ-eligible projects and programs.

For more information, please contact Anne McGahan, MPO staff, at 857.702.3676 or