Tu-Uyen Tran, Forum Communications, Published June 26 2011
Souris crests in Minot; uncertainty heads downstream to Velva, Sawyer
“The key here is control; that’s what we want,” said Lt. Col. Kendall Bergmann, deputy district engineer for the U.S. Army Corps of Engineers’ St. Paul district.
The corps controls the flood-control dam at Lake Darling upstream of Minot, and it’s been able to reduce the flow of water headed for the city and slowly bring down the level of water at the lake. This results in more capacity in case more rain water comes down the river from Canada.
For the next several days, it appears the Souris River Valley can expect a lot less water, both from the sky and in the river itself.
That means Minot’s Flood of 2011 reached a record level of 1,561.7 feet above sea level, as measured from the Broadway bridge gauge, according to the National Weather Service. It beats the previous record holder, the flood of 1881, by 3.7 feet, and the devastating flood of 1969 that folks here are still talking about by 6.3 feet.
But now that the crest has passed Minot, the state’s fourth largest city with a population of 41,000, the uncertainty that it brings heads downstream to Sawyer, population 360, and Velva, population 1,100.
Both those cities declared mandatory evacuations Saturday night, emptying the streets for workers to bring in clay, and by the end of the day Sunday were able to finish their temporary levees, according to Bergmann. Now they wait for the projected crest, expected today, and watch to make sure the fast-moving water doesn’t erode dikes.
The city of Velva reported that it had to halt levee construction Saturday night when the levees on the west side of town were dangerously eroded. All resources, including a North Dakota National Guard “quick response team” were mobilized to patch the levee with clay and sandbags. Plastic and rocks were used to armor the levee against the rushing waters.
The same levee reinforcement efforts were ongoing in Minot.
Mayor Curt Zimbelman reported close calls at several spots along the levees there.
In one spot, crews had to build a new ring dike to contain the leakage, according to Shannon Bauer, a spokeswoman with the corps.
Efforts of this kind will likely continue for days until the river level drops.
In Minot, the Broadway bridge, the only direct link between the two halves of the city that’s been bisected by the swollen river remains closed to traffic other than flood fighters and emergency vehicles. The mayor said he expects it will stay that way at least another week. The city doesn’t want a lot of traffic that could block clay-bearing dump trucks should an emergency occur.
The end of the flood is increasingly in sight, however.
Upstream near the Canadian border, the Souris River gauge near Sherwood shows a significant drop in the river level since the crest of 27.9 feet Thursday night. As of 3:30 p.m. Sunday, the river was at 26.2 feet. That’s a lot less water coming out of Canada.
Zimbelman said Canadian reservoirs are reducing the flow of water into the Souris River system. They’d earlier had to increase the flow to avoid overtaxing the dams when a large thunderstorm dumped large amounts of rain in southern Saskatchewan.
Knowing that Lake Darling won’t be seeing a lot more water from up north has allowed the corps to throttle back the flow of water out of the reservoir. On Saturday morning, 25,000 cubic feet per second was coming out of the dam. On Sunday, it was down to 23,000 cfs, and, according to the mayor, the corps will reduce that amount by 1,000 to 2,000 cfs a day for the next two weeks.
No significant chance of rain is in the National Weather Service for the next seven days, except for the 40 percent chance of thunder storms Thursday night, long after the crest has passed most of the towns on the U.S. side of the Souris River valley.
Canada’s Weather Office forecasted a thunderstorm over southern Saskatchewan Sunday night and early this morning and showers on Thursday.
Tu-Uyen Tran writes for the Grand Forks Herald