Transportation Planning:

State and Metropolitan Planning Agencies Report Using Varied Methods to Consider Ecosystem Conservation

GAO-04-536: Published: May 17, 2004. Publicly Released: Jun 10, 2004.

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The nation's roads, highways, and bridges are essential to mobility but can have negative effects on plants, animals, and the habitats that support them (collectively called ecosystems in this report). Federally funded transportation projects progress through three planning phases: long range (20 or more years), short range (3 to 5 years), and early project development, (collectively defined as planning in this report) before undergoing environmental review (which includes assessing air and water quality, ecosystems, and other impacts) required under the National Environmental Policy Act. Federal law requires planners to consider protecting and enhancing the environment in the first two phases, but does not specify how and does not require such consideration in the third phase. GAO reported on (1) the extent to which transportation planners consider ecosystem conservation in planning, (2) the effects of such consideration, and (3) the factors that encourage or discourage such consideration. GAO contacted 36 planning agencies (24 states and 12 of approximately 380 metropolitan planning organizations), as well as officials in 22 resource agencies that maintain ecological data and administer environmental laws. The Department of Transportation and U.S. Army Corps of Engineers had no comments on a draft of this report. The Department of the Interior generally agreed with the contents of our draft report.

Of the 36 transportation planning agencies that GAO contacted, 31 considered ecosystem conservation in transportation planning, using a variety of methods. For example, Colorado conducts studies that incorporate ecosystem issues to guide future transportation decisions, uses advance planning to avoid or reduce impacts, and actively involves stakeholders. New Mexico uses planning studies to identify locations where wildlife are likely to cross highways and design underpasses to allow safe crossings. In the absence of specific requirements, federal agencies encourage ecosystem consideration in planning. Planners and state resource agency officials most frequently reported reduced ecosystem impacts and improved cost and schedule estimates as positive effects. For example, planners in New York changed a planned fivelane highway to a lower-impact two-lane boulevard after weighing the area's mobility needs and the project's impact on the surrounding habitat. In Massachusetts, resource agency officials said that addressing ecological requirements in planning improved schedule certainty during the federally required environmental review. Furthermore, planners and resource agency officials reported that working together has improved relationships between their agencies, thereby allowing ecosystem concerns to be resolved in a more timely and predictable manner. Officials also listed negative effects, such as higher project costs and more work for resource agencies. Constituent support from agency staff, political appointees, or the public was the most frequently reported factor (27 instances) that encouraged planners to consider ecosystem conservation. For example, New Mexico's "pro-environment" culture reportedly encourages planners to consider ecosystem conservation. The cost in time and resources of considering ecosystem conservation was most often cited as a discouraging factor (23 instances). For example, Colorado planners cited the significant amount of time needed to collect and maintain access to ecosystem data.

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