Modeling the Mouse: Future Flood Risk for the Souris River

Release Date:

The Souris, or Mouse, River Basin is currently in a wet climate period and will be at high flood risk for some time, according to a scientific model published today by the U.S. Geological Survey.

The Souris, or Mouse, River Basin is currently in a wet climate period and will be at high flood risk for some time, according to a scientific model published today by the U.S. Geological Survey.

 

“This new tool can help managers and citizens better prepare for and mitigate hazards along the Souris for protection of life and property during floods and drought,” said USGS scientist Kelsey Kolars, the lead author of the report.

Kolars and her colleagues with the USGS and the North Dakota State Water Commission developed a model of potential future streamflow for the Souris River of North Dakota and Canada. The model estimates the likelihood of future severe flooding on the Souris.

The scientists based the model on historical meteorological and streamflow data for the Souris River Basin, as well as tree ring records dating back to the early 1700s. The data showed several extreme wet and dry periods and a significant climate transition in 1970, with 1912 – 1969 representing a dry climate state and 1970 – 2011 representing a wet climate state.

Flood risk is considerably higher for the wet state compared to the dry state. For example, during the wet state, the annual volume of water flowing into Rafferty Reservoir in Saskatchewan, Canada, has about a three percent chance per year of exceeding 513,000 acre-feet, or 633 million cubic meters – the maximum storage capacity of the reservoir. For the dry climate state, the chance is only about 0.5 percent per year.

According to the model, the 1970 – 2011 wet state continues to persist. The model does not specify precisely how long the wet period will last.

“Future flood risk will remain high until the wet climate state ends, and for several years after that, as there may be a long lag-time between the return of drier conditions and drying out of soil and surface water storage,” Kolars said.           

The Souris River flows from the southeast corner of Saskatchewan into North Dakota and continues northward into Manitoba, Canada. During the spring of 2011, record-setting flooding along the Souris caused devastating damage to numerous downstream communities, including over 4,000 flooded homes in Minot, North Dakota.

For more information about streamflow on the Souris River, please visit the USGS Streamgages in the Souris River Basin in U.S. and Canada webpage.