Beaches on the brink

Saving incredible shrinking shorelines among top environmental concerns

Tropical storm Francis caused extensive damage along the Texas coast in 1998. States bordering the Gulf of Mexico lose about 6 feet a year to erosion

September 20, 2000
Web posted at: 6:30 PM EDT (2230 GMT)

In this story: Coastal concerns The danger of global warming Shoring up strategies LESSON PLAN RELATED SITES

By Christy Oglesby
CNNfyi Senior Writer

The country is shrinking.

This time last year the United States was about 5 feet wider and 7 feet longer. Erosion -- gradual land loss -- has claimed at least that much of the coastline.

Since the United States stretches 9.6 million square miles and has more than 12,000 miles of coastline, loosing a few feet of beach here and there might not seem significant. But it is.

Click below to see facts about erosion in the United States
Source: The H. John Heinz III Center for Science, Economics and the Environment

That land loss is cumulative. And a government study released in the spring shows that during the next 60 years, one-fourth of houses within 500 feet of the U.S. shoreline could be destroyed. Property loss, which runs about $500 million a year in coastal areas, certainly concerns land-owning adults. But the flooding and threats to ecosystems that erosion brings affects everyone.

"The ecological concerns crop up because of the scarcity of wetlands," explained Philip Keillor of the University of Wisconsin Sea Grant Institute, which offers advice about coastal construction. "We have filled in so many wetlands that when the ocean takes (or destroys) a wetland, then it's significant because we don't have that many left."

Shores along the Atlantic Coast shrink by 2 to 3 feet a year, according to an erosion study conducted by the H. John Heinz III Center for Science, Economics and the Environment in Washington. The Heinz Center is a nonprofit institution dedicated to improving the scientific and economic foundation for environmental policy.

States bordering the Gulf of Mexico lose about 6 feet a year to erosion and have the nation's highest annual land loss.

	MAP
View the average erosion rates across the country

Erosion rates vary widely along the Pacific Ocean. Steep cliffs line that body of water. And because they are made up of crumbly rock, the cliffs can lose tens of feet at one time in one spot while losing nothing 50 feet away, the study says.

Erosion along the Great Lakes also varies greatly. Because of changes in lake levels there could be no land loss at all or shoreline losses as great as 10 feet.

Hay bales are used as the core of artificial dunes on Galveston Island, Texas. The bales are an economical way of rebuilding dunes and encouraging the regrowth of dune vegetation

"Nobody can control or prevent erosion," said Stuart Stevens, chief of ecological services with the Georgia Department of Natural Resources. "All you can do is manage it."

Erosion is closely linked to sea levels. As the climate heats up, polar ice caps melt, and seas go up. Depending on which expert you ask, the seas have risen somewhere between 6 inches to 3 feet in the last century. The higher they go, the less land you have.

"There are some expectations that rise might accelerate during the next 50 to 100 years because of global warming," said Bob Friedman, one of the researchers who conducted an erosion study for the Federal Emergency Management Agency.

Storms, hurricanes and the way rivers empty also wear away the shore. While erosion is a natural, unpreventable phenomenon, humans make it worse.

Harbors, seawalls, dredging, manmade inlets, jetties and bulkheads all contribute to erosion. They affect natural water currents and prevent sand from shifting down coastlines to replenish beaches, Stevens said.

People have three choices when erosion poses a threat. Leave, renourish or build.

Years ago, people moved when land started to disappear, Stevens said. But beachfront lots can cost as much as $1 million, so not many people would likely abandon their homes.

Last year the National Park Service moved the Cape Hattaras, North Carolina, lighthouse back 2,900 feet to a more stable position

When erosion threatened to destroy the Cape Hatteras lighthouse in North Carolina, the National Park Service spent $9.8 million to move the beacon back 2,900 feet. In 1870, that lighthouse was 1,500 feet from the shore. In 1987, it was 160 feet from the water.

In Glynn County, Georgia, where Stevens works, the beach loses 1 to 2 feet of shore each year. The county is starting a beach renourishment project. The Georgia Department of Natural Resources will take sand from underwater sandbars and heap it onto the shore, making the beach 15 feet higher and 300 to 400 feet wider.

There is not a uniform approach to managing erosion, and each county, city and municipality has the liberty to choose its own solution.

Other solutions include erecting vertical walls, pouring sloping concrete along the coast or heaping rocks at the edge of the shoreline.

"The reason erosion gets so much attention is our large financial investment along the coastline," said Keillor of the University of Wisconsin Sea Grant Institute. "Erosion has always been going on. It wouldn't be a problem except that we build too close to the coast. . . . Our approach is to advise people to stay back."

Great Lakes
Heinz Center
National Ocean Service
Coastal erosion
Losses from coastal erosion

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