Streamlining Transportation Conformity Processes

Focus Area

Air Quality


Air Quality






2-3 years

Research Idea Scope

The transportation conformity regulation (40 CFR Parts 51 and 93) has been amended repeatedly since “Conformity provisions first appeared in the Clean Air Act Amendments [CAA] of 1977 (Pub. L. 95-135)”, to quote the historical perspective provided by the US Environmental Protection Agency (EPA) in its proposed rule for transportation conformity in 1993. There is now a critical need to undertake a comprehensive review of processes as currently implemented by state DOTs and MPOs to comply with conformity requirements, develop realistic cost estimates for those compliance activities and, most importantly, identify to the extent feasible cost-effective options for streamlining the compliance process while meeting all regulatory requirements. The need stems from two challenges: • First, the incremental changes introduced by the ongoing series of amendments have resulted in a relatively complex regulation that is increasingly challenging and costly to implement at both the regional and project-levels, i.e., marginal costs have increased while marginal benefits have decreased (or disappeared). For example, for areas that currently have a substantial margin between forecast emissions and the applicable budgets, passing the regional conformity tests is typically a foregone conclusion, so the six-to-twelve month or more period of time spent on modeling and consultation is effectively a waste of resources. Why take the time and money to do extensive modeling and consultation if the results are known in advance? There has to be a more cost-effective way to show compliance in these cases, e.g., by a programmatic approach, which is time-tested in other applications (such as for NEPA.) • Second, periodic and occasionally unpredictable court rulings have introduced significant uncertainty (if not a degree of chaos) into the conformity process. For example, the February 2018 court ruling on the revocation by EPA of the 1997 ozone NAAQS was a surprise decision that has led to a national-level conformity crisis, with federal agencies struggling to react with appropriate and timely guidance pending the results of an EPA petition for rehearing, state and local transportation agencies suffering costly impacts due to an immediate and possibly (lacking federal guidance) retroactive conformity lapse, and our customers, users of the transportation system, ultimately paying all the costs. Such periodic conformity crises are unacceptable and, if they cannot always be avoided, means to mitigate the impacts and allow for more cost-effective and realistic responses are needed. The study may be phased and include surveys of state DOTs and MPOs, as well as case studies. For example, the first phase may identify issues and potential solutions, while the second may involve the detailed cost assessments and analyses of options for streamlining. In the first phase, the study may survey State DOTs and MPOs and select a small number facing varying degrees of complexities (from simple to highly complex) in implementing conformity requirements and in their ability to respond to conformity crises (such as from unexpected court rulings). In the second phase, the study may work with the selected state DOTs and MPOs to develop case studies and assess the potential benefits of proposed options for streamlining.

Urgency and Payoff

State DOTs and MPOs would benefit from the development and implementation of options to streamline conformity compliance activities, which have become increasing time-consuming and costly, especially with unexpected court rulings causing national-level conformity crises. Contacts: Christopher Voigt, VDOT and Kevin Black, FHWA

Suggested By

Christopher Voigt Virginia DOT 804.371.6764

[email protected]