ATLANTA — The Chattahoochee River is back on the top 10 list of endangered rivers in the country for the first time in more than a decade.

Officials with the American Rivers organization, which compiles the list, cited a proposal to dam Flat Creek in north Hall, as he reason for the river’s reappearance on the list. Hall County officials want to impound the creek to create an 850-acre reservoir.

American Rivers officials say the proposal to build Bear Creek Reservoir in South Fulton County is also a “significant threat” to the river.

Hall County officials say the construction of a reservoir is critical to ensure the county’s future water supply.

But the U.S. Army Corps of Engineers must approve the project and corps officials are awaiting the results of an impact study before approving the reservoir. That decision likely will be made some time next year.

Jenny Hoffner, the director of water supply for American Rivers, said the group hopes to draw attention to the proposals to dam the Chattahoochee and what she says is a larger trend across the country to build reservoirs.

She says stronger conservation measures would be preferable to building reservoirs. But a number of state officials including Lt. Gov. Casey Cagle say there is no way to conserve enough water to ensure an adequate water

supply.