Flood in Olmsted County, Minnesota

Flooding occurred on most of the rivers, streams, and creeks throughout the county. Water caused at least 20 road closures throughout the county, which included U.S. Highway 52 north of Oronoco as well as County Roads 105, 14, 31, 18, 5 and 133. Seven of the roads were damaged, 3 of which saw extensive damage. Two vehicles tried driving across a water covered road in Oronoco and were swept away. The people in the vehicles were rescued safely. Across the county, 81 homes incurred major damage, while 10 homes had minor damage. Of those 91 homes with damage, 50 occurred in the city of Oronoco. In the city of Eyota, the sewer system was full and many homes had water in their basements. A small subdivision in Rochester was evacuated due to rising water, while the majority of the Meadow Lakes Golf Course in southeast Rochester was underwater. The rain began the afternoon of the 22nd, with the majority falling by 6 a.m. CST on the 23rd. Rainfall amounts across the county as of 6 a.m. CST on the 23rd included 4.68 inches in Rochester, 4.54 inches near the Rochester Airport, 3.66 inches at the Maple Valley Golf Course, 3.47 inches at Dover, and 3.24 inches near Elgin.

A stationary front set up across southern Minnesota on the evening of September 22nd. As an unusually moist air mass flowed over this boundary, heavy rain developed and fell repeatedly across the area during the evening and overnight hours. Soils were abnormally wet for this time of year, therefore the extreme rainfall amounts that fell caused widespread significant river flooding and flash flooding. Infrastructure was greatly affected with millions of dollars of damage, while private properties were also heavily damaged. Dodge, Olmsted, Wabasha, Winona, and Mower counties were included in federal disaster declarations (FEMA-1941-DR).