Rainstorms are a challenge to clean water. They can cause flooding and potentially damaging runoff . But utilities, landscape architects and others are finding solutions — visible everywhere from the county grounds to your neighborhood ice cream shop. In 2011, MMSD built a large basin on the Milwaukee County Grounds. It's a 17-foot-deep sunken pool with grassy walls that, when full, looks like two connected natural lagoons. The basin can hold up to 315 million gallons of water. » See More