Road Design -- A Turn Ahead
by Edward McMahon

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Too often new roadways have been designed to be wider and straighter, without much consideration being given to the character of the surrounding community. In recent years, however, there has been a gradual turn towards more thoughtful, "context sensitive" roadway design. Edward McMahon looks at what's behind this change in direction.


From PCJ #40, Fall 2000
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photo by Edward McMahon
A familiar scene: widening a road. But a growing number of planners are claiming that wider & straighter roads are too often the wrong solution. Edward McMahon looks at current issues in roadway design.

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Has your local government ever been notified that the state highway department is planning to "improve" a rural scenic road, reconfigure a congested suburban intersection, or replace a historic bridge in your community?

Each year American communities are presented with plans to expand or rebuild streets, roads, and bridges. Whether the community is rural or suburban, in Eastern Oregon or Northern Virginia, the explanation is almost always the same. A road that local people are accustomed to is said to be deficient. It does not conform to the latest standards. It is not wide enough or it has too many curves. Unless something is done, motorists will experience delays or unsafe conditions.

Plans are presented that call for a road that is straighter, flatter, and above all, wider than before. The highway department calls the project a road "improvement," but many local citizens are opposed to the project. Why? Because conventional road widening and bridge reconstruction projects often damage scenery, natural resources, and community character for little or no real benefit.

The conventional approach to road design aims to move more traffic faster, at the expense of everything else. In her book, The Living City, author Roberta Gratz tells the story of a small town that seeks help with repairs to an aging bridge, only to be told that repairing the bridge is "not cost efficient." Only by widening the two-lane bridge to four lanes would federal funds be available. Adding two lanes, however, will require widening and straightening the road that provides access to the bridge. This will, in turn, require using adjacent parkland, cutting down a row of 100-year-old trees, and demolishing several historic buildings. When local residents oppose the out-of-scale solution they are accused of opposing progress and are told federal rules "require" the new wider bridge.

Does this sound familiar? Well it should because this scenario, in one form or another, has been repeated through America. Over-scaled, over-priced highway projects are imposed, where smaller, less expensive, equally useful and more environmentally benign solutions would do.

While environmentally harmful, oversized, highway projects are familiar to us all, the good news is that this all-too-common way of designing roads and bridges is being challenged. A growing number of citizens, planners, and local officials are demanding that local transportation improvements incorporate "context-sensitive" highway design (also known as "place sensitive" or "flexible" highway design) to preserve community character and environmental resources. ...

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