Wauwatosa’s Hart Park expanded from 20 acres to 50 acres when MMSD completed its $48 million flood management project near the city’s thriving downtown. Together, the bigger park and a series of flood levees help temporarily store floodwater that could otherwise damage homes and businesses or get into the sewer system, raising the threat of basement backups and sewage overflows.

Flood proof amenities added to Hart Park by the community

The park itself actually stores floodwater until the Menomonee River recedes to lower flow conditions after a storm. Construction crews removed one-to-three feet of earth from the storage area in the park and hauled it away. It’s important to note that the park will remain dry the vast majority of the time, except when strong storms cause flooding in the Menomonee River. Hart Park is designed to work along with three other projects on the Menomonee River to harness and protect against the one percent probability flood, commonly called the 100 year flood. Floods larger than the one percent probability can still spill over the levees and storage areas.