Rains send sewer overflows into Milwaukee-area waterways

Don Behm in the Milwaukee Journal-Sentinel brings some news about one of the most glamorous parts of adaptation to climate change -- combined sewer overflows!: The street flooding and backups of water and sewage into basements after heavy rainfalls of up to 5 inches this week have refocused public discussion in Milwaukee on improving public and private sewers. Overflows of combined sanitary and storm sewers to local rivers and Lake Michigan in central Milwaukee and east Shorewood were expected to end Wednesday evening, Milwaukee Metropolitan Sewerage District officials said. Estimates of the volumes of those overflows were not available late Wednesday.

Earlier in the day, the Milwaukee Common Council's Public Works Committee discussed the findings of a task force - convened after catastrophic flooding in July 2010 - that extreme weather events, including torrential rains, are increasing in frequency in the upper Midwest because of climate change. Without sewer upgrades, basement backups will continue to be a problem, said Milwaukee Ald. Jim Bohl, who led the task force.

The task force recommended helping homeowners keep excessive flows of clear water from rain and melting snow out of residential sanitary sewer laterals. Laterals empty into municipal sanitary sewers, and the excess water quickly fills the pipes, causing wastewater to back up into homes along low portions of streets. Cracked or damaged laterals allow water to leak into the sewers, Bohl said. Clear water directly flows into laterals where foundation drains are connected to the pipes.

A demonstration project this summer in Bohl's west side district is focused on upgrading laterals and disconnecting foundation drains at up to 560 homes in the Cooper Park neighborhood. Basement backups have been reported in the area after heavy summer rainstorms in each of the last three years. A city official said more than 90 basement backups were reported across the city Monday and Tuesday. Completing the project, as recommended by the task force, should determine whether such work is cost effective, Bohl said….

A sewer overflow in Rhode Island, from an EPA photo