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Highway and Transit Program Reauthorization: An Analysis of Environmental Protection Issues

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Balancing public needs for surface transportation infrastructure with protecting the environment has been a long-standing issue among states and local communities. These two objectives can often conflict due to the rise in pollution that typically results when new highways or roadways are constructed, or a highway is expanded, to provide greater traffic capacity. Expanding highway capacity can be especially challenging for states, if the resulting rise in pollution would be great enough to make compliance with federal air quality standards more difficult. In order to receive federal highway funds, the Clean Air Act requires states with air quality problems to demonstrate that their transportation plans conform to their plans to control emissions, referred to as "transportation conformity."

To help reduce potential conflicts between highway capacity needs and environmental requirements, Congress has authorized the use of federal highway funds to alleviate some of the pollution resulting from highway construction and travel. The most recent multi-year funding authorization for these activities was provided in the Transportation Equity Act for the 21st Century (TEA-21, P.L. 105- 178), which expired at the end of FY2003. How to meet state needs for highway infrastructure, while ensuring compliance with environmental requirements, is among the key issues for reauthorization.

TEA-21 authorized a total of $218 billion for federal highway and transit programs from FY1998 to FY2003. It set aside $9 billion for air quality projects, including $8 billion for the Congestion Mitigation and Air Quality Improvement Program (CMAQ) to offset some of the emissions from highway travel, as a means to assist states in complying with federal air quality standards. The other $1 billion was authorized for the purchase of clean fuel transit buses. TEA-21 also expanded funding eligibility to allow states to use federal highway funds for mitigating water pollution from highway runoff. The law also authorized funding for environmental research and the development of advanced vehicle technologies, and it included several other provisions related to environmental protection.

The use of federal highway funds to address environmental needs has focused mostly on air quality projects, due primarily to requirements for states to demonstrate conformity as a condition for receiving federal highway funds. Most of this funding has been provided under the CMAQ program. While the program's effectiveness has been questioned, there is broad support for increasing its funding in response to an upcoming rise in air quality needs among the states. Other air quality issues involve the use of transit funding for the purchase of clean fuel buses, offering tax benefits for cleaner-burning alcohol-based fuels, and exempting certain low-emission vehicles from High Occupancy Vehicle (HOV) lane requirements. The extent to which water pollution mitigation projects and environmental research and development activities should be eligible for federal highway funds are issues as well.

This report provides background information and analysis of key issues to serve as a resource document for the reauthorization debate. It will not be updated.


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