Flood — Waukesha, Wisconsin

2025-08-10 to 2025-08-13 · near Menomonee Falls, Waukesha, Wisconsin

Event narrative

Widespread flooding of streets, creeks, rivers, and low lying neighborhoods and homes continued over the eastern half of the county and was aggravated by additional showers and storms. The greatest concentration of flooding was in New Berlin, Brookfield, Butler, Menomonee Falls, Waukesha, Pewaukee, Merton, and Muskego. Some of the more notable creeks or rivers that flooded were the Fox River, Menomonee River, Jewel Creek, Butler Ditch, Root River, and their tributaries, as well as some lake flooding. Some flood damage occurred to homes especially near Linnie Lac toward Little Muskego Lake. These damages were from a variety of 1st floor flooding, basement flooding, and foundation collapse. Residential sewage backups, and raw sewage released into rivers by many municipalities were common. A small number of complete road washouts and swift water rescues occurred, in addition to dozens of people stranded in their vehicles in deep, still water in low lying areas. More specifically, one lane of Gold Dr. washed out due to the flash flooding of Jewel Creek in Muskego. Large sections of Barker Road in Brookfield and other nearby roads were closed due to the flash flooding of the Fox River, including the Fox River overtopping the Barker Rd. bridge. A partial road washout occurred on Lily Road in Menomonee Falls due to the flash flooding of a tributary of the Menomonee River. The large collapse of a Y-shaped intersection at Campbell Dr. and Campbell Ct. in Menomonee Falls also occurred due to the flash flooding of Butler Ditch. 130 St. in New Berlin was partially washed out from the flash flooding of a tributary of the Root River. Dozens of people were evacuated or relocated from their flooded homes and neighborhoods, which included the Deer Path Subdivision near Minooka Park and homes near Linnie Lac. A sidewall of the Merton Millpond Dam was damaged but quickly repaired. Many other dams in eastern Waukesha County were at or exceeding their maximum flow capacity, but no dam failures occurred. River flooding along the Lower Fox River in Waukesha peaks during the evening of August 11, with a 8.62 foot crest in moderate flood stage occurring at 5:15 PM local time. Moderate river flooding continues along Lower Fox River in Waukesha through the morning hours of August 13. In moderate flood stage, water from the Lower Fox River approaches the base of the Bastow St and Bank St Bridges in downtown Waukesha, in addition to some homes in the Bethesda Court area about one half mile south of downtown Waukesha. Water also inundates the Frame Park area, with waters at least 3 feet deep on land near the shoreline of the Lower Fox River. Water approaches Corrina Blvd and Union St to the south of downtown Waukesha.

Wider weather episode

A historic flash flood and record rainfall occurred over portions of the Milwaukee Metropolitan Area and Southeast WI resulting in damages in the $100s Millions. Warm, moist, and unstable air rose along a stalled front to produce numerous thunderstorms and more than 10 inches of rain in many locations. Widespread flash flooding of streets, creeks, rivers, and low lying neighborhoods occurred. A homeless camp in Milwaukee underneath 1st Street Bridge adjacent to the surge of record flooding on the Kinnickinnic River was swept away. One or two deaths may be a result of this flash flooding with a couple others missing. Thousands of residential homes or businesses sustained major flood damage with dozens classified as destroyed due to 1st floor flooding, basement flooding or foundation collapse. Residential sewage backups, and raw sewage released into rivers and Lake MI by many municipalities was common. A small number of complete road washouts and swift water rescues occurred, in addition to dozens of people stranded in their vehicles in deep, still water in low lying areas. First responders had difficulty getting to their 911 calls including stranded motorists and flooded neighborhoods, due to the numerous flooded roads. Dozens of people were evacuated or relocated from their flooded homes and neighborhoods. Longer duration areal flooding and river flooding, which ranged from moderate flooding to record flooding, then continued for a couple more days. In addition to the flash flooding, a couple hikers were struck by lightning, via a ground current from a nearby strike on a tree, on the Ice Age Trail near Palmyra. They were initially rendered unconscious but did survive.

View location on OpenStreetMap → (43.1921, -88.0635)

Source: NOAA Storm Events Database, event_id 1282399. Narrative written by the NWS forecast office that issued the report.