Several Chattanooga streets wend their way up ridge lines or straddle the edges of deep creeks. Every day, these same roads risk rocks falling on them or the streets washing away entirely, city officials said.

"The roads are falling off the side of the hill," Lee Norris, deputy administrator for the city's Department of Public Works, said. "That's what's happening."

At least four city roads risk "slope failures," the same types of rock slides that closed U.S. 64 in the Ocoee Gorge for about five months between November and April and squeezed Signal Mountain Boulevard down to one lane for about two weeks in December, city officials said.

In a valley shaped by glaciers thousands of years ago, the terrain still is changing.

"We're trying to fight Mother Nature," said Eddie Tate, the city's pavement supervisor.

There is not much that can be done right now except monitor the areas and patch roads to extend their lives, he said.

"You can kind of patch it," he said. "That's a short-term fix."

The cost for fixing these roads, which include Hamill Road, Lake Resort Drive, Main Street near Missionary Ridge and an area along Interstate 24 between Old Ringgold Road and South Crest Road, would be about $1 million each, he said.

Councilwoman Pam Ladd, chairwoman of the Public Works Committee and the person who represents the areas of Hamill Road and Lake Resort Drive, said the city's hands are tied when it comes to fixing the roads.

"It's going to take a lot of money and (is) not something we can put in the budget this year," she said. "All we can do is monitor."

An additional problem with Lake Resort Drive and Hamill Road is that they lie next to bodies of water, Mr. Tate said. The portion of Lake Resort Drive that could wash away lies next to Chickamauga Lake. A section of Hamill Road lies just 15 feet away from North Chicka-mauga Creek.

Parts of Missionary Ridge are falling toward Main Street, Mr. Tate said. On Interstate 24, there are portions of the hillside falling toward the busy road at the ridge cut, which the state maintains, he said.

Bob Niswonger, who lives on Northshore Drive off Lake Resort Drive, said if anything happened to Lake Resort it would be an inconvenience.

"I would just have to take the other way on Hamill Road," he said.

Told that portions of Hamill Road also are a risk, he said that would be even more of an inconvenience. He would have to travel all the way down Gann Store Road to Hixson Pike to get to the city, he said.

Michael Porter, general manager of Lakeshore Marina on Lake Resort Terrace, said there's no doubt his business would drop if Lake Resort Drive slid away. He said many of the marina's customers come off busy Highway 153 onto Lake Resort Drive because they are from out of town and see

advertisements for the marina.

Many local residents could take Hamill Road to get to the boat docks because they know of the alternate route, he said, but if both roads went out there would be problems.

Phillip Grimes, executive director of Outdoor Chattanooga, said his organization takes trips up and down North Chickamauga Creek from Greenway Farms, located on Hamill Road. If the road fell into the creek, Outdoor Chattanooga would change its trips, he said.

"It would affect us more traffic-wise," he said.

Fewer people would want to try to figure out a way to get to Greenway Farm, he said.

He mentioned people could come in from Gann Store Road off Lake Resort Drive or Hixson Pike. But both roads sliding off into the water could be devastating, Mr. Grimes said.

"If we got boxed in, it would definitely affect us," he said.

Interactive graphic: Slope failures