In 2004, multiple storms in Milwaukee caused a series of overflows that sent untreated sewage into waterways that empty into Lake Michigan. While the area sewerage district’s “deep tunnel” inline storage system helped keep the number of overflows down, it was impossible to eliminate them.Inflow and infiltration of stormwater runoff into the sanitary sewer was a big contributor to the problem. In response, the 28 communities that comprise the Milwaukee Metropolitan Sewerage District (MMSD) are looking at ways to curtail I&I.For the district’s biggest member, the City of Milwaukee, manholes have been a big area of focus. As part of
