Flash Flooding in Wisconsin, July 22, 2010

Law enforcement officials reported numerous road closures and culverts damaged due to deep and rushing water over roads from near Portage to Randolph, and south to the Dane County border. Included in these reports was damage to culvert supports in the Harmony Grove subdivision and damage to roads shoulders and driveways along Cactus Acres Road in Lodi; knee-high water covering Henry Drive in Portage. Storm total rainfall reports include 3.68 inches in Lodi; 3.58 inches in Arlington; and 2.58 inches near the Wisconsin Dells, with much of the rain falling within one to two hours of time.

Emergency managers reported numerous road closures due to flash flooding in the southern half of the county. Included in the reports were washed out shoulders along roads in the Reeseville and Lowell areas. Law enforcement officials reported street flooding at the intersection of Mill Street and Grant Street, and along Maple Avenue in Beaver Dam made the streets impassable. A trained spotter reported 1.5 to 2 feet of water over the road at the intersection of CTH DJ and CTH E about 3.5 miles southeast of Clyman. Storm total rainfall reports include 3.42 inches at Hustisford; 3.24 inches in Juneau; 2.40 inches in Beaver Dam; and 2.36 in Horicon, with much of the rain falling within one to two hours of time.

Training thunderstorms produced 2.5 to 4.5 inches of rain in about two hours over mainly the northern half of the county. Street flooding stranded cars in Sun Prairie, various locations in the city of Madison, Oregon, Middleton and DeForest. Three to four feet of water covered the intersection of Commercial Avenue and Ckronke Road in Sun Prairie, stalling cars and filling some home basements and commercial buildings with water, that damaged contents.

Police officials closed Clinton Street just west of U.S. Highway 45 in Kewaskum due to flooding. Sandbagging operations were needed on Little Cedar Lake due to rapidly rising lake levels from the heavy rain. Street flooding was reported in West Bend with a trained spotter in town recording 1.77 inches of rain that fell in 25 minutes. A trained spotter in the Barton area about 1.5 miles north of West Bend reported significant flooding on area roads and 6 inches or more of standing water covering the yards of residences in his neighborhood. The floodwater damaged the contents of flooded basements in the area. He recorded 2.03 inches of rain in about 45 minutes. Storm total rainfall amounts include 4.60 inches in Richfield; 4.51 inches at Holy Hill; and Germantown 3.13 inches.

A trained spotter reported 3 feet of water over South Business Drive between Riverdale Avenue and Stahl Road in the town of Wilson 5 miles south-southwest of Sheboygan. Another trained spotter reported street flooding on the south side of the city of Sheboygan near the intersection of Weeden Creek road and 10th Street. The flooding damaged the contents of flooded basements and washed out gravel shoulders of roads.

Police reported runoff from heavy rains caused a few sewer backups in homes causing damage to contents in Mequon. Police also reported water over roads in Cedarburg, draining with enough force to pop off a manhole cover near the high school. Law enforcement also closed I-43 at both Mequon Road and County Line Road, mainly due to impassable conditions due to flooding just over the county line in Milwaukee. Thiensville officials reported 2.85 inches of rain in less than 2 hours, while Mequon received 2.84 inches.

Thunderstorms training over the region produced flooding rains over all of Milwaukee County...causing massive flooding, shutting down streets and the freeway system at rush hour with up to 4 feet of rushing water.

There was one fatality - the body of a 19-year-old male was found in Lincoln Creek near N. 32nd St. and W. Hampton Ave. in Milwaukee. He was swept from his vehicle when Lincoln Creek flooded.

County Executive Scott Walker issued a Declaration of a Major Disaster for Milwaukee County since more than 7 inches of rain fell around the county, and an estimated $24.1 million in damage in the private sector, and nearly $11.6 million in public sector costs, which includes protective measures and clean-up costs.

The private sector damage costs include: $22,396,790 dollars to residential buildings and $1,686,752 dollars to businesses. The public sector costs include: $2,003,010 dollars of damage to public buildings and equipment; $2,385,760 dollars of damage to public utility systems; $2,774,400 dollars or damage to road systems; $310,000 dollars of damage to water control facilities and another $1,326,100 dollars in damage to other public property for a total of $8,799,270. In addition, another $1,946,100 dollars were spent in debris clearance and $894,988 dollars were spent for overtime. These costs are not directly related to the flood damage.

The Milwaukee Fire Department logged 50 rescues from homes and streets.

The Milwaukee Metropolitan Sewerage District (MMSD) reported that the storm resulted in a combined sewer overflow of around 2 billion gallons. All Lake Michigan beaches in Milwaukee were closed through the following weekend of July 24th and 25th due to sewer contamination. The City of Milwaukee received at least 2000 calls for sewer backups into basements of homes. It appeared that the northern half of the city of Milwaukee was hardest hit.

The flooding rains created a massive sink hole 20 feet deep and some 20 to 40 feet wide at the intersection of Oakland and North in the city of Milwaukee around 830 pm. It swallowed a Sport Utility Vehicle and a street light. The driver of the SUV was injured and treated at a hospital. Electrical power cables and other cable lines were damaged by the sink hole.

Milwaukee Mitchell International Airport was closed late Thursday night (July 22nd) through 2 pm Friday (July 23rd) due to flooded runways. One runway was opened at 2 pm Friday, however there were additional delays.

In Milwaukee County, over 4,400 homes reported water-filled basements in the city of Milwaukee alone.

11,764 homes received some sort of impact from the flooding, with 6 homes destroyed; 57 homes receiving major damage; 1,859 home receiving minor damage; and an additional 9,842 homes minimally affected by the flood waters. Sixty-eight businesses were affected, with 9 having major damage and 59 having minor damage.

The north side of the city received the heaviest downpours with 7 to 8 inches of rain falling in 2 to 3 hours. WTMJ-TV4 on Milwaukee's northeast side measured 6.73 inches of rain in 1 hour, between 5:15 pm and 6:15 pm. The twenty-four hour rainfall (midnight to midnight July 22nd) was 8.31 inches. They also received another inch of rain after midnight on July 23rd, so the two-day total was 9.31 inches.

The Milwaukee Fire Department logged 50 rescues from homes and streets.

Nicolet High School in the north suburban community of Glendale had a completely flooded basement and 16 of water on the main floor.

Hourly rainfall amounts of 2 to 4 inches were reported, and WTMJ TV-4 on Milwaukee's northeast side measured 7 inches of rain in about 2.5 hours ending at 745 pm Thursday evening. The one-hour rainfall was 6.73 inches between 5:15 PM and 6:15 PM CDT in the late afternoon/evening. The twenty-four hour rainfall (midnight to midnight July 22nd) was 8.31 inches, with another inch after midnight on July 23rd, so the two day total was 9.31 inches.

Mitchell Field recorded 5.61 inches for the day, breaking a record for the date. The previous record was 1.26 set in 1948. This also is the second highest daily rainfall total on record for Milwaukee. The greatest one-day precipitation record was the 6.81 inches which fell on August 6, 1986.

Training thunderstorms produced 2.5 to 4.5 inches of rain in about two hours over mainly the northern half of the county. Street flooding stranded cars in Sun Prairie, various locations in the city of Madison, Oregon, Middleton and DeForest. Three to four feet of water covered the intersection of Commercial Avenue and Ckronke Road in Sun Prairie, stalling cars and filling some home basements and commercial buildings with water, damaging their contents.

Thunderstorms training over the region produced 4 to 7 inches of rain over Waukesha County. While many sections of the county experienced flash flooding, the north and northeast sections were hardest hit, with numerous roads flooded and basements flooded in Brookfield, Menomonee Falls and Sussex. A trained spotter reported 4 inches of rain in one hour in Menomonee Falls where the heavy rains caused a sink hole to form on Campbell Drive. Rushing water flooded roads in Delafield near U.S. Highway 18, closed STH 59 at STH 164 south of Waukesha, and covered sections of CTH Z, west of Eagle in western Waukesha County. Flooded roads were also reported in Muskego, New Berlin and Oconomowoc.

Training thunderstorms produced 3 to 5 inches of rain in two hours or less across mainly the northern two-thirds of the county. Many roads were rendered impassable for a time due to the heavy downpours. Localized flooding of roads and some basements, with damage to contents, were reported by the county emergency manager in Waterloo, Watertown, Lake Mills, Jefferson, Ixonia and Johnson Creek. STH 19 was closed east of Watertown due to high water over the road. Some storm total rainfall reports include 5.45 inches at Palmyra; 4.97 inches in Milford; 4.70 inches at the National Weather Service office in Sullivan; and 4.59 inches in Waterloo.

The southern edge of a line of training thunderstorms pushed across northern portions of Racine County, producing between 3 and 4 inches of rain in two hours or less. water covering area roads made them impassable, including CTH G at I-94, with the flood waters washing out gravel shoulders. Basements flooded, causing damage to contents, including the basement of a home on Spring Street on the northwest side of the city of Racine, flooded with water from the swollen Root River.