After nearly 10 years of discussion, Sandy Springs is set to vote on a contract for a final design to repair the “high-hazard” Lake Forrest Dam at a Sept. 17 City Council meeting.

The contract recommended by city staff is to be awarded to Schnabel Engineering for $756,800.

Two alternatives have been proposed by the engineering firm: concrete box culverts, which would construct tunnels to carry the stream under Lake Forrest Drive, and a concrete channel with a bridge. The cities of Atlanta and Sandy Springs, which are jointly working on the repair, chose the culvert option.

“At this time…the cities have requested that Schnabel proceed with design services for the concrete box culvert option and to eliminate any consideration of a bridge over the spillway,” a city document says.

The alternative would require Lake Forrest to be closed for construction, as the dam runs directly beneath it, but the timeline of the closure is unknown.

The state Safe Dams Program has ordered repairs of the dam because it is on the state’s list of “high-hazard” dams, meaning that if it failed in a worst-case scenario, the flood would likely kill people downstream.

The repair has been a slow process because of complex ownership issues involving both Atlanta and Sandy Springs governments, as well as the private Three Lakes Corporation, a homeowners association that uses the pond behind the dam.

The two cities have agreed to split the cost of the project because the dam rests on the cities’ border, but it is still unclear what financial role Three Lakes will take in the project, if any.

To read the Emergency Action Plan for the dam filed with the state, click here.

The Reporter Newspapers has published a series of articles about “high-hazard” dams in our communities. Previous installments have looked at the location and condition of the 11 local “high-hazard” dams; the cost of maintaining these dams and the long process of repairing them; concerns about the lack of emergency plans in case of a dam failure and an overview of recently filed plans; and how the state inspects the structures.

Hannah Greco

Hannah Greco is writer and media communications specialist based in Atlanta.