Very dry spring expected, extremely low runoff outlook
The indicators continue to point toward a very dry spring. Soil moisture conditions are very low. Wetlands are well below capacity and there’s little snow on the landscape. Those conditions highlight the latest Flood and Water Resources Outlook issued by the National Weather Service for the Souris River Basin.
“The risk of widespread flooding in the Souris River Basin remains well below normal due to a combination of continued below normal snowfall and dry soils,” reads the Outlook. “In fact, based on current conditions, the chance of even minor flooding is less than 10 percent throughout the entire basin.”
It adds, “the stretch of dry weather dates back to last year.”
The Souris River at Westhope, the last reporting point on the Souris before it re-enters Canada and where high water is a near certainty every spring, is given only a six percent chance of reaching minor flood stage. Other reporting points – Sherwood, Foxholm, Boy Scout Bridge, Minot’s Broadway Bridge, Logan and Velva are given a less than five percent chance of reaching minor flood stage.
In short, unless conditions change dramatically with heavy snowfall or torrential rainfall, it will be drought conditions and not floodwater that will be of the greatest concern come spring. The latest moisture total recorded for the year at the Minot International Airport is a mere .11 inch, nearly a full inch below long-term expectations. The possibility is that similar weather patterns, namely a lack of moisture, will continue to prevail in the coming months.
A winter storm is forecast to enter North Dakota this weekend and continue into Monday. However, even in areas where up to four inches of snow is expected, it won’t carry enough moisture to alleviate drought conditions. The NWS puts it this way, “Despite the short-term hazards associated with this event, the moisture it brings will be viewed as more beneficial than threatening.”
As for spring flooding on the Souris or its tributaries, barring record rainfall, the only risk at this point is the possibility of high water due to unpredictable ice jams. Even that scenario, says the NWS, is limited.
“While ice jams and the high water they can cause are not mathematically predictable, a lack of strong runoff due to melting snow minimizes the risk of ice jams.”
Lake Darling northwest of Minot and two reservoirs on the Souris in Saskatchewan, Rafferty near Estevan and Grant Devine at Oxbow, are all at or below prescribed levels at this time. While all three reservoirs are poised to protect against excessive spring runoff, the greater concern at this time is whether or not there will be enough snowmelt runoff to lift the impoundments to their preferred summer operating levels.
Water being released into the Souris River continues to be minimal at 10 cubic feet per second. It is an effort to maintain the dissolved oxygen content in the Souris and, possibly, prevent a fish kill if dry conditions persist.