By Wauwatosa (WI) Mayor Theresa M. Estness
March 24, 2008

As the mayor of Wauwatosa (WI), board member of the Milwaukee Metropolitan Sewerage District (MMSD), and member of the Conference of Mayors Water Council, I have been deeply involved with water quality improvement efforts over the last several years. In our metropolitan region, we have taken aggressive action to reduce fecal coliform loadings to comply with environmental regulations and to protect human health. We turned a significant corner in 1994 through a combination of traditional and green infrastructure investment, including innovative programs aimed at reducing pollution from point and non-point sources urban runoff. The measurement data has consistently demonstrated that these efforts have had a positive impact.

Wauwatosa and 27 other cities in metropolitan Milwaukee are serviced by MMSD. There are two wastewater treatment plants: Jones Island and South Shore. The wastewater system is comprised of 300 miles of MMSD sewer lines, with another 3,000 miles of community sewer lines feeding into the system. An additional 3,000 miles of sewer lines from private property owners also feed into the system.

Wet weather overflows, a substantial regulatory compliance concern, had to be addressed in order to reduce the fecal coliform loadings into Lake Michigan. Unfortunately, the only way to prevent sewage from backing up into the basements of area homes is to provide relief to the overburdened sewer line with a sewer overflow. To reduce the risk of both undesirable actions, area communities contributed to a traditional infrastructure investment approach called the “Deep Tunnel System.” It was designed to reduce overflows from 50 to 60 each year down to one or two. Wet weather conditions are natural phenomenon (uncontrollable circumstances), and urban development patterns over the years have added to the intensity and volume of water that flows into sewers.

The Tunnel was built 300 feet below ground, and is 17 to 32 feet in diameter extending some 19.4 miles. The Tunnel is capable of sequestering 405 million gallons of water from sewer lines. The Tunnel system was enhanced in 2006 with an additional seven-mile extension that added another 89 million gallons of storage. Another deep tunnel is currently under construction, and will hold an additional 27 million gallons of wastewater. It has dramatically reduced overflow volumes into Lake Michigan.

Yet, the Tunnel system is not perfect, and we still experience beach closings when bacteria levels climb above safe levels. Think about this however: we will still have beach closings even if we do not have any sewer overflows. There’s a lot more out there polluting our waterways than just sewer overflows. We recently finished the most intensive scientific research ever conducted on our watersheds. It found that 89 percent of the fecal coliform bacteria getting into our waterways comes from polluted stormwater runoff. Surprising to some, the largest source of this particular pollution is coming from urban areas. Rural, agricultural lands come in a close second place.

Many have had polluted runoff on their radar screens for years, but aggressive efforts to tackle the issue are complex, despite some simple, low cost techniques. At MMSD, we have sold more than 7,000 rain barrels to residents for $30 a piece. That’s 385,000 gallons of water we’re keeping out of the sewers and from becoming polluted runoff each time it rains. Demand for the barrels is growing with little advertising, but rain barrels alone will not solve the problem. Cleaning up polluted runoff requires many different tools and the understanding by everyone that almost everything we do in our watersheds impacts the quality of our waterways. That includes policy and decision-making on land use.

That is why we have invested in green infrastructure approaches as well as innovative programs to reduce the volume of urban runoff. Some of those efforts have yielded impressive results, both for protecting water quality and reducing flooding risks. Lincoln Creek experienced frequent flooding. It was redesigned by removing the concrete channel and maximizing the recharge capacity of the immediate flood plain. Now it is less prone to flooding and has attracted more wildlife. The design has transformed from concrete eyesore to pastoral eye candy for our residents.

“Green Seams” have been introduced over the last decade to increase pervious surfaces and wetlands areas. In 2006, 454 acres of Green Seams were protected. Working with nearly a million dollars in grants since 2001, we have converted over 1,600 acres into Green Seams. This has had a substantial impact on reduced flooding, and has vastly improved standing wetlands and water recharge that filters contaminants from runoff. This green infrastructure approach prevents runoff from contaminating Lake Michigan and it reduces treatment and energy use/expense at the treatment plants.

Another innovative initiative is the 28-community stormwater ordinance implemented in 2002. All land development is subject to a limiting standard (applied to impervious areas greater than one-half acre). Two standards were adopted. The 100-year runoff release rate is limited to 0.5 cfs/acre of new impervious surface. The two-year runoff release rate is limited to 0.15 cfs/acre of new impervious surface.

The communities, in conjunction with MMSD, kickeoff a public education campaign to help citizens reduce runoff. Property owners are encouraged to engage in a variety of activities that reduce runoff and promote water conservation. For example, homeowners are encouraged to disconnect downspouts that feed into sanitary sewers. Instead, they can build rain gardens and/or use rain barrels that can serve to irrigate lawns and shrubs. Tree planting is encouraged to capture water flow, reduce flooding and avoid soil erosion that can clog storm drains and contaminate water bodies. Businesses and institutions are encouraged to install green roofs that can reduce runoff and cool buildings during the high temperature months.

While these innovative approaches at the local level have had positive impacts on water supply and conservation, one of the crowning achievements is a 50 percent reduction in fecal coliform loadings from 1975 to 2000. The traditional and innovative actions taken by the MMSD communities have had a demonstrably positive effect. It proves that focusing on abating stormwater runoff can yield substantial benefits and can generally improve the quality of life and sustainability of our cities.