Friday, June 25, 2021

Big rains over the past couple of days in southeast Iowa have produced a curious anomaly: today the Des Moines River is bigger than the Iowa portion of the Mississippi River. As I write this, the flow on the Des Moines River at Keosauqua is 56,900 cubic feet per second, while the flow of the Mississippi at Clinton is 29,600 CFS. This does happen occasionally: 32 days in the last 100 years. But the magnitude of the difference today (27,300 CFS) is the second biggest ever, exceeded only during the historic Des Moines River flood of June, 1947 (35,600 CFS).

discharge on Des Moines river