JAMESTOWN, N.D. — Less water is being released from Pipestem Dam and more from the Jamestown Dam as the water levels at both reservoirs are approaching the target elevations, according to James Dixon, dam manager at Pipestem Dam for the U.S. Army Corps of Engineers.
"Pipestem Dam has just a half foot to go," he said. "As the release from the Pipestem Dam is reduced, we went from 450 cubic feet per second to 500 cfs at Jamestown Dam."
Dixon said the intent was to keep the downstream flow of water consistent to prevent the collapse and breakup of river ice that could then form ice jams and cause flooding.
Jessica Batterman, hydraulic engineer for the Corps of Engineers, said the goal is to have both reservoirs at the target elevations by March 1. While the Pipestem Reservoir only has about 6 inches of excess water at this point, the Jamestown Reservoir is about 2 feet above its target.
"The most recent forecast is that we should be right near that date," she said. "The plan is to drop a couple of feet below the usual winter water levels."
The Corps of Engineers controls releases when the reservoirs are above flood control levels. Once the level falls below that, probably on or about March 1, releases will be controlled by the U.S. Bureau of Reclamation, the owner of Jamestown Dam.
"Our advice to the Bureau has been to maintain releases for ice stability," Batterman said. "We should have more information by the end of the week."
Batterman said unless the amount of snow on the ground in the upper basin, areas above the Jamestown and Pipestem dams, increases drastically in the next weeks, the Jamestown area should have little problems with river flooding.
Forecasts by the Corps of Engineers show that combined releases from Jamestown and Pipestem dams should not exceed 1,800 cfs this spring unless a lot more moisture is added to the basin above the dams, she said.
If possible, releases will be lower than 1,800 cfs in order to ease flooding concerns in downstream communities such as LaMoure or into South Dakota, Batterman said.
Sandbags placed by the city of Jamestown last fall were designed to protect the city to releases of 2,400 cfs and are still in place, said Jerry Bergquist, Stutsman County emergency manager and 911 coordinator.
"What is forecast now doesn't cause any issues in Jamestown," he said.
Bergquist said the recent days with above-freezing temperatures have not caused any runoff into local streams and there have been no reports of rising water in the sloughs outside the James River.
"Two things are potentially happening," he said, regarding the snow that is disappearing with the warmer temperatures. "Some might be going into the soil; some might be evaporating. Either is a good thing."
Batterman cautioned that a few days of high temperatures above freezing does not mean we are into spring weather.
"We look at the forecasts going out about two weeks because they are the most accurate," she said. "The forecasts indicate no significant snowmelt in that period."