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This executive summary plus thousands more available at http://www.nap.edu
Assessing and Managing the Ecological Impacts of Paved Roads
http://books.nap.edu/catalog/11535.html
1
Summary
There are 4 million miles of roads in the United States. One hundred years ago, roads were primarily unpaved and had half the number of
miles of the present U.S. road system. As the system grew, roads became wider and more complex structurally to provide for more and heavier traffic. New construction technology and greater structural stability
were needed to improve the road system.
All phases of road development—from construction and use by vehicles to maintenance—affect physical and chemical soil conditions, water flow, and air and water quality. Roads alter habitats, increase wildlife
mortality, and disperse nonnative pest species of plants and animals. At
larger scales, roads affect wildlife migration patterns. In some cases,
roads can also enhance roadside habitats for native species.
The importance of integrating environmental considerations into all
phases of transportation is emphasized in legislation. The Transportation
Equity Act for the Twenty-First Century (TEA-21) of 1998 called for
protection of the environment by initiating transportation projects that
would improve environmental quality and support fuel efficiency,
cleaner fuels, and alternative transportation. The act called for streamlining procedures to reduce red tape and paperwork in transportation project
reviews without compromising environmental protection.
Consideration of environmental issues in road development has
been an evolving process. The increasing awareness of environmental
issues, regulatory changes, and new solutions have made road development more complex and controversial. Many believe that environmental
protection can be compatible with streamlining the project approval
process through effective planning and coordination. Suggestions on
This executive summary plus thousands more available at http://www.nap.edu
Assessing and Managing the Ecological Impacts of Paved Roads
http://books.nap.edu/catalog/11535.html
1
Summary
There are 4 million miles of roads in the United States. One hundred years ago, roads were primarily unpaved and had half the number of
miles of the present U.S. road system. As the system grew, roads became wider and more complex structurally to provide for more and heavier traffic. New construction technology and greater structural stability
were needed to improve the road system.
All phases of road development—from construction and use by vehicles to maintenance—affect physical and chemical soil conditions, water flow, and air and water quality. Roads alter habitats, increase wildlife
mortality, and disperse nonnative pest species of plants and animals. At
larger scales, roads affect wildlife migration patterns. In some cases,
roads can also enhance roadside habitats for native species.
The importance of integrating environmental considerations into all
phases of transportation is emphasized in legislation. The Transportation
Equity Act for the Twenty-First Century (TEA-21) of 1998 called for
protection of the environment by initiating transportation projects that
would improve environmental quality and support fuel efficiency,
cleaner fuels, and alternative transportation. The act called for streamlining procedures to reduce red tape and paperwork in transportation project
reviews without compromising environmental protection.
Consideration of environmental issues in road development has
been an evolving process. The increasing awareness of environmental
issues, regulatory changes, and new solutions have made road development more complex and controversial. Many believe that environmental
protection can be compatible with streamlining the project approval
process through effective planning and coordination. Suggestions on