Souris river should behave
The Souris River is expected to remain well within its banks this spring in the Minot area. That was the major message contained in the latest Hydrologic Outlook for the Souris issued by the National Weather Service Thursday.
It was good news for a region that experienced historic flooding along the Souris in 2011.
While the latest outlook projects a favorable runoff this spring, there are still areas of concern. For the Souris, the greatest risk of problems associated with future runoff is downstream of Minot.
“The risk of overland flooding has gone up substantially from our first outlook,” said Allen Schlag, Bismarck NWS hydrologist. “I’m talking about the Willow Creek area, out of Lake Metigoshe to Upham. That’s where I think the biggest difference is from our last issuance.”
A recent storm added up to a foot of snow in the Towner area, particularly to the north. The latest addition to the snowpack is one of the primary reasons for an expected increase in runoff reaching major tributaries of the Souris, including Willow Creek and Wintering River. As a result, the Westhope reach of the Souris is once again projected to reach flood stage. It is a situation not uncommon for that portion of the river, and generally produces little damage to an area where high water in the spring is a frequent occurrence.
Flood stage at the Westhope gauge on the Souris, which is located east of the city and within the boundaries of the J. Clark Salyer National Wildlife Refuge, is 10 feet. The latest outlook calls for a 95 percent chance the Souris will reach an elevation of 10.4 feet with a flow of nearly 1,900 cubic feet per second at the Westhope gauge. Such a flow would remain well within the river valley and not affect any buildings.
Even if the recorded flow at the Westhope gauge would reach 5,200 cfs – the approximate flow necessary to reach what is considered moderate flood stage at that location, or 14 feet – flooding would basically be limited to refuge lands. The latest outlook rates the possibility of the Souris reaching 14 feet at Westhope at 25 percent.
For the City of Minot, where major flooding occurred in 2011, a key measuring point on the Souris is Broadway Bridge. Thursday’s outlook gives the Souris a 50 percent chance of reaching 1,545 feet, well below flood stage of 1,549 feet. The flood of 2011 reached a crest of 1,561.8 feet at Broadway Bridge.
Although there was a recent snowfall of substance in the Minot region and significant amounts of snow are reported on the ground in Saskatchewan, where the Souris River originates, concerns of a repeat of the flooding in 2011 are diminished.
“Right now we don’t have as much water sitting on the ground as we did in 2011,” explained Schlag. “The snowpack is less. The location is different. It is very advantageous to North Dakota and especially Minot. The heaviest snow (in two locations) is still above the Rafferty and Alameda Reservoirs in Saskatchwan, and well downstream from Minot.”
Storage in the Canadian reservoirs and Lake Darling northwest of Minot, is at prescribed levels for this time of year and are expected to be able to handle the anticipated runoff. Still, there are reasons for river watchers to remain vigilant.
“There’s going to be plenty of water moving through the Souris River, I’m convinced of that,” said Schlag. “Even in the most gentle melt conditions there’s going to be plenty of water within easy reach of problematic flooding. Conditions to keep an eye out for are three or four days of upper 30s or low 40s combined with a reasonable chance of rain. A ripened snowpack will rapidly disappear if you get a rainstorm over it.”
Schlag defined “problematic flooding” as situations when sandbagging may begin in some low-lying areas or flooding would top some roads in rural areas. As far as the Souris though, says Schlag, “this is all stuff the Souris River can handle.”
In some years the Des Lacs River contributes a considerable amount of water that flows through the Souris in Minot. The Des Lacs flows south out of the Kenmare region and joins the Souris at Burlington. Often the Des Lacs is responsible for flooding along its path. At this time though, spring flow in the Des Lacs is expected to be limited.
“The Des Lacs does not look very problematic for us, but it has proven to be very susceptible to heavy rains,” noted Schlag. “Given the current conditions and a normal spring, the Des Lacs should be pretty quiet.”
The Souris and Red Rivers in North Dakota rank among those having the highest frequency of automated river gauges of any drainages in the U.S. They provide information of river levels throughout the runoff season. The U.S. Geological Survey, which oversees gauges along the Souris, has issued a notice that some gauges in the U.S. may become inoperable due to federal budget cuts known as sequestration.
A USGS spokesman in North Dakota said no such cuts have been ordered for gauges on the Souris and that all Souris River gauges in the network remain operational. Nationally the USGS oversees a network of approximately 8,000 river gauges. According to their website, about 375 of the gauges are in jeopardy of being discontinued.
Still to come is the latest runoff outlook from the Water Security Agency in Saskatchewan. Although information from Canadian sources figures prominently in Hydrologic Outlooks issued by the NWS, attention must still be given to runoff projections provided by the WSA. A WSA spokesman in Moose Jaw, Sask., said the latest outlook for Souris River runoff in the province of Saskatchewan is being compiled and could be ready for release as early as next week.