The Milwaukee Metropolitan Sewerage District (MMSD) is using green stormwater infrastructure (GSI) to meet an ambitious goal to capture, absorb and store 740 Million Gallons of water EVERY TIME IT RAINS. The project is called Fresh Coast 740.
The goal is to prevent flooding by slowing down the flow, prevent the damage caused by the force of water running off impervious surfaces and allow water to be reabsorbed onsite, remove pollutants, reduce water volume in the sanitary sewer system, and harvest rain to use where treated drinking water is not required (such as landscape irrigation).
Here’s an interesting comparison–Seattle’s program is called the 700 Million Gallons project and the goal is to capture 700M gallons of polluted runoff per YEAR. The MMSD plans to do more than that with every single rain event.
Manage Water Where It Falls
How will they do it? By managing water where it falls through the creation and use of green stormwater infrastructure. These GSI techniques will cover a variety of methods including bioswales, permeable pavement, green roofs, new trees, rain gardens, downspout disconnection and rainwater harvesting through the use of cisterns and rain barrels.
While 740 million gallons may seem like a large number, it’s actually small considering the actual rainfall volume. The MMSD website tells us that “one inch of rain in their service area equals 7.1 billion gallons of water.”
Implementation of successful GSI program’s throughout the district is imperative to hit that goal. In order to recognize and congratulate successful participants, MMSD has created the “Green Luminaries” award and is giving out awards monthy to recognize leadership and implementation of green stormwater infrastructure.