Transportation conformity is required by the Clean Air Act section 176(c) (42 U.S.C. 7506(c)) to ensure that federal funding and approval are given to highway and transit projects that are consistent with ("conform to") the air quality goals established by a state air quality implementation plan (SIP).
The intent of Transportation Conformity is to fully coordinate transportation and air quality planning to ensure that the Regional Transportation Plan (the Plan) and the Transportation Improvement Program (TIP) projects which are analyzed will not a) cause or contribute to any new violation of the National Ambient Air Quality Standards (NAAQS), b) increase the frequency or severity of any existing NAAQS violations, or c) delay timely attainment of the NAAQS or any required interim emissions reductions or other milestones in any area.
What does a Transportation Conformity Determination involve?
Through Transportation Conformity Determinations, NYMTC quantitatively demonstrates how its Plan and TIP projects impact future motor vehicle emissions budgets. In general, NYMTC conducts transportation conformity once per year. To determine transportation conformity, NYMTC:
- Forecasts mobile source emissions for a Regional Transportation Plan and Transportation Improvement Program (TIP).
- Compares mobile source emissions forecasts to emissions budgets set in the State Implementation Plan (SIP) for Air Quality.
- Establishes that emissions budgets will not be exceeded.
Nonattainment and Maintenance Areas Addressed by NYMTC
Nonattainment and maintenance areas are subject to Transportation Conformity. Areas where air quality monitoring shows a violation of the NAAQS are designated “nonattainment.” Nonattainment means that an area has monitored air quality that does not meet the NAAQS. Once a nonattainment area is shown through air quality monitoring to have met a NAAQS, USEPA will designate the area as a "maintenance area."
NYMTC’s Transportation Conformity Determinations address all nonattainment and maintenance areas that fall in whole or in part within the NYMTC planning area, including:
- The New York-Northern New Jersey-Long Island, NY-NJ-CT Ground-level Ozone (VOC, NOx) Nonattainment Area, which includes all NYMTC counties and boroughs except for Putnam County;
- The New York-Northern New Jersey-Long Island, NY-NJ-CT Fine Particulate Matter (PM2.5) Maintenance Area, which includes all NYMTC counties and boroughs except Putnam County, as well as Orange County
- The New York-Northern New Jersey-Long Island, NY-NJ-CT Carbon Monoxide Limited Maintenance Area, which includes and the five New York City boroughs and Westchester and Nassau counties.
Transportation Conformity Determination Documentation
NYMTC prepares a Transportation Conformity Determination document to demonstrate that its Regional Transportation Plan (RTP) and Transportation Improvement Program (TIP), as updated, are in compliance with the mobile source emission budgets for the air quality nonattainment and maintenance areas that fall in whole or in part within the NYMTC Planning Boundary.
For more information contact Afolabi Aiyedun