TOLNA, N.D. - Engineers could begin investigating the cause of a leak in the Tolna Dam as early as Tuesday, four days after a tiny crevice in the structure on a tributary of the Sheyenne River had grown to 5 feet, prompting a temporary flash flood watch for the immediate area.
The flood watch was lifted Sunday, after the water level dropped by about 2 feet, according to Bruce Engelhardt, an engineer with the North Dakota State Water Commission.
"As the water continues to drop, we'll do a more thorough inspection," Engelhardt said.
The concrete and rock structure operated by the Nelson County Water Resource District was built in 1937, creating a 147-acre reservoir on the Tolna Coulee
The dam has been repaired several times, Engelhardt said, most recently in 2008, when crews stopped a leak. That project cost about $60,000.
ADVERTISEMENT
A 10-mile stretch of North Dakota Highway 15, downstream from the dam, was closed overnight Friday as a precaution.
He said no downstream homes were threatened and that even if the dam had failed, it likely would have had little, if any, impact on Lake Ashtabula, a reservoir north of Valley City.
