US Department of Transportation

FHWA PlanWorks: Better Planning, Better Projects

US Department of Transportation

FHWA Planworks: Better Planning, Better Projects

Transportation Conformity


Areas designated as air quality nonattainment or maintenance areas for the transportation-related pollutants have special meaning to transportation professionals. Transportation improvement projects in these areas must undergo a rigorous analytical process to demonstrate that they do not negatively impact air quality. In addition, there is a collaborative interagency consultation partnership between Federal agencies, the State DOT, and local government representatives that supports conformity analysis.

Transportation conformity ("conformity") is a way to ensure that Federal funding and approval goes to those transportation activities that are consistent with air quality goals. Conformity applies to transportation plans, transportation improvement programs (TIPs), and projects funded or approved by the Federal Highway Administration (FHWA) or the Federal Transit Administration (FTA) in areas that do not meet or previously have not met air quality standards for ozone, carbon monoxide, particulate matter, or nitrogen dioxide. These areas are known as "nonattainment areas" or "maintenance areas," respectively. Regulations governing transportation conformity are found in Title 40 of the Code of Federal Regulations (40 CFR Parts 51 and 93).

Hover over the highlighted Key Decisions to understand the specific relationship of transportation conformity to the decision. Click on any highlighted Key Decision for more information about questions, data, and relationships that support this interface. Key Decisions that are greyed-out have no specific relevance to the individual application or topic area but are still accessible from this graphic.

LRP-1
https://fhwaapps.fhwa.dot.gov/planworkst/DecisionGuide/Step/LRP-1

Collect information on conformity deadline and emissions budget, as well as available technical data related to conformity.
LRP-2
This Key Decision is not associated with application
LRP-3
https://fhwaapps.fhwa.dot.gov/planworkst/DecisionGuide/Step/LRP-3

Consider target emissions levels in the development of criteria, methods and measures.
LRP-4
This Key Decision is not associated with application
LRP-5
This Key Decision is not associated with application
LRP-6
This Key Decision is not associated with application
LRP-7
This Key Decision is not associated with application
LRP-8
This Key Decision is not associated with application
LRP-9
https://fhwaapps.fhwa.dot.gov/planworkst/DecisionGuide/Step/LRP-9

In nonattainment and maintenance areas for the transportation-related pollutants, review and approve the conformity analysis to determine that the preferred scenario meets all Federal requirements, including current conformity requirements.
LRP-10
This Key Decision is not associated with application
LRP-11
https://fhwaapps.fhwa.dot.gov/planworkst/DecisionGuide/Step/LRP-11

In nonattainment and maintenance areas for the transportation-related pollutants, FHWA/FTA must make a Federal conformity determination.

PRO-1
This Key Decision is not associated with application
PRO-2
This Key Decision is not associated with application
PRO-3
This Key Decision is not associated with application
PRO-4
This Key Decision is not associated with application
PRO-5
This Key Decision is not associated with application
PRO-6
https://fhwaapps.fhwa.dot.gov/planworkst/DecisionGuide/Step/PRO-6

In nonattainment and maintenance areas for the transportation-related pollutants, make conformity determination for the TIP.
PRO-7
This Key Decision is not associated with application
PRO-8
This Key Decision is not associated with application
PRO-9
https://fhwaapps.fhwa.dot.gov/planworkst/DecisionGuide/Step/PRO-9

In nonattainment and maintenance areas for the transportation-related pollutants, FHWA/FTA must make conformity determinations.

COR-1
This Key Decision is not associated with application
COR-2
This Key Decision is not associated with application
COR-3
This Key Decision is not associated with application
COR-4
This Key Decision is not associated with application
COR-5
This Key Decision is not associated with application
COR-6
This Key Decision is not associated with application
COR-7
This Key Decision is not associated with application
COR-8
This Key Decision is not associated with application
COR-9
https://fhwaapps.fhwa.dot.gov/planworkst/DecisionGuide/Step/COR-9

In non-attainment and maintenance areas, consider air quality conformity impacts of the various projects or strategies in the corridor plan during prioritization for consistency with the long-range transportation, TIP and/or STIP.

ENV-1
https://fhwaapps.fhwa.dot.gov/planworkst/DecisionGuide/Step/ENV-1

Collect relevant data about air quality, including emissions budgets and potential partnerships.
ENV-2
This Key Decision is not associated with application
ENV-3
https://fhwaapps.fhwa.dot.gov/planworkst/DecisionGuide/Step/ENV-3

Gather information about the air quality context for the region, including the status of conformity, to inform the definition of purpose and need.
ENV-4
This Key Decision is not associated with application
ENV-5
https://fhwaapps.fhwa.dot.gov/planworkst/DecisionGuide/Step/ENV-5

Consult with interagency partners on project-level analysis, where applicable.
ENV-6
This Key Decision is not associated with application
ENV-7
This Key Decision is not associated with application
ENV-8
This Key Decision is not associated with application
ENV-9
This Key Decision is not associated with application
ENV-10
This Key Decision is not associated with application
ENV-11
This Key Decision is not associated with application
ENV-12
This Key Decision is not associated with application
ENV-13
https://fhwaapps.fhwa.dot.gov/planworkst/DecisionGuide/Step/ENV-13

For non-attainment and maintenance areas, approve and document the project-level conformity determination.
ENV-14
This Key Decision is not associated with application