Engineers are studying the possibility of building a second outlet on Devils Lake to more quickly draw down the lake to prevent a possible spillover into the Sheyenne River.
Staff members of the North Dakota State Water Commission are working on options involving a second outlet on Devils Lake, now about 6 feet below its natural outlet.
The idea is to draw water from northwest Devils Lake, where better water quality would enable bigger controlled releases of water, engineer Bruce Engelhardt said Friday.
The analysis will be completed "as soon as possible," probably later this summer, he said.
Officials are increasingly worried about the possibility of an uncontrolled release of water from Devils Lake into the Sheyenne, which would threaten downstream cities including Valley City, Lisbon and Kindred.
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The U.S. Geological Service estimates the chances of exceeding the spillover level on Devils Lake by 2019 at 10.3 percent with no state outlet and 6 percent with an outlet. The chance of spillover increases by 2029 to 13.8 percent without a state outlet to 7.7 percent with the outlet.
Now there is no control structure on the Tolna Coulee, where Devils Lake naturally begins flowing into the Sheyenne River at an elevation of 1,458 feet above sea level. The lake was 1,451.74 feet Friday afternoon.
Meanwhile, work continues on a project to more than double pumping capacity of the existing outlet south of Minnewaukan to hasten efforts to gradually draw down the lake.
That project, which would increase the pumping capacity from 100 to 250 cubic feet per second, is expected to be completed in July.
The biggest constraint on the outlet, however, involves water quality standards that often prevent or limit releases from the outlet.
Water in Devils Lake is high in unhealthy sulfates. An emergency rule has lifted the level of allowed sulfates in the upper Sheyenne, above Baldhill Dam on Lake Ashtabula, from 450 to 750 milligrams per liter, but leaves the level below Baldhill dam at 450.
That's why engineers are looking at a second outlet on the northwest shore of the lake, where the water is lower in sulfates, Engelhardt said.
By releasing fresher water, a new outlet could be operated more frequently, and also might be able to release flows at a higher capacity, he said.
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"We aren't far enough into the process" to reach a conclusion, he added. Nor is there an estimated price tag. "It won't be cheap," Engelhardt said.
A special legislative committee will meet in Devils Lake on Monday and Tuesday to hear testimony on the economic and emotional effects of the prolonged flood, which began in 1993 and has cost, by some estimates, $1 billion.
"We want to come out of there with a plan to present to the Legislature," said Sen. Tom Fischer, R-Fargo, chairman of the Water-Related Topics Overview Committee.
Besides the continued devastation to the Devils Lake region, the possibility of a spillover into the Sheyenne River is of major concern because an estimated 40 percent of North Dakota's population lives downstream, Fischer said.
To alleviate flooding and prevent a spillover, officials would like to reduce the lake by 5 feet, he said.
Already, higher and more frequent high flows along the Sheyenne have caused problems for the West Fargo diversion. Officials want to spend $8 million to $9 million to rip-rap two stretches of the diversion to stabilize banks.
Patrick Springer is a reporter at The Forum of Fargo-Moorhead, which is owned by Forum Communications Co.
