Living in the southeastern part of Sioux Falls I have seen the Big Sioux River Flood at Spencer and Tuthill Park probably a dozen times. I've never seen it with icing on top until now.
An incident at the Smithfield Foods wastewater treatment plant resulted in higher that allowed limits of ammonia, which were discharged into the Big Sioux River.
A couple weeks ago I wrote about how the City of Sioux Falls lets the grass grow tall along the Big Sioux River and some other parks in order to filter storm run-off.