Flood in Codington County, South Dakota

The Big Sioux River at Watertown Broadway Avenue stream gauge would report flooding during the late morning of August 22nd, peaking on the evening of the 22nd at 10.90 or 0.90 feet above flood stage. The river would remain in flood at this section through the early morning of August 24th.

Storms moved over portions of northeast South Dakota that had really no extra room for moisture from the preceding months of nearly constant rainfall. Thus, this moisture went straight into the Big Sioux and tributaries from the Watertown area down south to Castlewood. The COOP observer in Rauville would record 1.51 inches of rainfall pushing their monthly total up to 5.73 and a 3 month total of 23.32. The Watertown COOP would likewise come up with 1.86 inches, putting the monthly total at 5.85 and 20.1 for the preceding 3 months. Even Castlewood, while only topping out at 0.31 inches, would see their monthly total top out at 4.99 inches with a 3 month total of 22 inches.