Environmental Impact of Paving and Road-building

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11-28-07, 9:23 am



EARTH TALK From the Editors of E/The Environmental Magazine Dear EarthTalk: The impacts of all the paving that is done for new roads and parking lots must be considerable. Other than Joni Mitchell’s “They paved paradise and put up a parking lot” issue, what else is this activity doing that will come back to haunt us? -- Libby Morse, via e-mail

The history of paving dates back to Roman times if not earlier, but our modern society has taken the practice to the extreme. Originally conceived as a way to make dirt- and mud-covered thoroughfares passable, roads (and parking lots) now cover the majority of urban and suburban areas around the world. In the U.S. alone, pavement covers some 60,000 square miles, or about two percent of the nation’s total surface area. One out of every 10 acres of arable land is paved over.


Beyond larger issues like urban sprawl and the loss of farmland, paving itself is an environmental scourge, preventing the natural seepage of rainwater at the soil surface, and increasing the volume and speed of water run-off. The result is often severe soil erosion on adjacent unpaved areas. Also, paving reduces the total area through which the soil absorbs rainwater, forcing pollutant-laden run-off quickly to lower ground, increasing the risk of flooding accordingly.

Another environmental problem created by our overzealous application of asphalt is that, because the soil underneath paved areas absorbs very little water, natural aquifers below can dry up, reducing the overall amount of potable water available to people, wildlife and the larger ecosystem. Paving also prevents the growth of plant life and destroys wildlife habitat.

According to the nonprofit American Farmland Trust, which works to preserve farmland and promote healthier farming practices, Americans lose three acres of productive farmland to new paving every single minute of every day. The group reports that since the first Earth Day in 1970, the U.S. has lost more than 40 million acres of farmland to development. With Americans now spending upwards of $200 million a day building and rebuilding roads, such problems are only getting worse.

In response to such concerns, a diverse coalition of 170 community groups, individuals and businesses came together in 1990 as the Alliance for a Paving Moratorium (APM), with the goal of addressing the “tremendous environmental, social and economic damage caused by endless road building.” The group charges that our society’s obsession with paving and road-building draws public funds away from alternative transportation projects in service to the automobile, destroys inner cities as it promotes sprawl, fouls the air and water, contributes to global warming and—because most asphalt is a product of fossil fuels—plays into ongoing conflicts in the Middle East.

Jan Lundberg, a former oil-industry insider and transportation policy analyst who helped create APM, sees a bright future in putting less emphasis on paving and roads: “Money would immediately become available for public transportation and making cities more walkable. It could also go toward refurbishing existing downtown buildings so that people could live in them. Parking lots could be de-paved to make gardens and parks. Cities can be pleasant places, you know.”

CONTACTS: American Farmland Trust, www.farmland.org; “The High Costs of Paving,” www.culturechange.org/issue19/high_costs.htm.

GOT AN ENVIRONMENTAL QUESTION? Send it to: EarthTalk, c/o E/The Environmental Magazine, P.O. Box 5098, Westport, CT 06881; submit it at: www.emagazine.com/earthtalk/thisweek/, or e-mail: earthtalk@emagazine.com. Read past columns at: www.emagazine.com/earthtalk/archives.php.