Compensating for Development

About the author: Emily Sievers is staff ecologist for Applied Ecological Services Inc. Sievers can be reached at 608.712.3585 or by e-mail at [email protected]. Lars Higdon is a UW-Madison graduate student in the Department of Landscape and lead steward at the university’s Lakeshore Nature Preserve. Higdon can be reached by e-mail at [email protected].

Emily Sievers & Lars Higdon

With its campus situated along the southern shoreline of Lake Mendota, the first and largest in a chain of five lakes along Wisconsin’s Yahara River, UW-Madison would be remiss not to manage its storm water runoff in an innovative and environmentally responsible manner. Faculty, staff and students have been eager to research and design effective new strategies for storm water management on the UW-Madison campus, hoping to set an example for a basin-wide initiative to protect the Yahara lakes as urban development expands.

A New Policy

The Campus Planning Committee officially adopted a new campus storm water policy on Oct. 2, 2003, with the goal of mitigating additional runoff from newly developed and redeveloped sites with compensatory storm water management practices. Ken Potter, civil and environmental engineering professor, emphasized that the amount of runoff from developed sites “be no greater than the amount that occurred under native conditions.”

UW-Madison has launched various storm water projects.

The new accounting system has led to a holistic approach to storm water management on the UW-Madison campus, where mitigation measures are implemented on site and off site to ensure the most effective and practical runoff control strategies. For accuracy, the campus uses the Wisconsin Stormwater Planner to predict development impacts on regional surface and groundwater systems and plan appropriate best management practices (BMPs).

Upon the adoption of the new storm water management resolution, graduate students in the 2003 Water Resources Management Workshop prioritized potential storm water management projects and identified opportunities for increased on-campus infiltration, erosion control and compaction remediation. UW-Facilities Planning and Management has implemented a number of suggestions and installed innovative BMPs in an effort to meet the new storm water management standards.

Here are three examples that illustrate UW-Madison’s commitment to protecting and enhancing the quality of area lakes, streams, wetlands and groundwater:

1. Parking Lot Upgrade
   After years of continual use, a 300-stall campus parking lot near the shores of Lake Mendota had to be replaced. With the assistance of a $150,000 Department of Natural Resources Urban Nonpoint Source and Storm Water Management Grant—plus other funds—the university constructed a new lot. One quarter of the area was repaved with storm water-absorbing permeable pavement, and a 6,250-sq-ft bioswale retention basin was constructed with native planting borders to absorb excess runoff.
2. Runoff Separation
   With crews constructing many new buildings on the west end of campus, storm water runoff has been a major concern in this area. To mitigate the problem, runoff from the newly built Interdisciplinary Research Center and the American Family Children’s Hospital has been managed so that relatively clean roof water is kept separate from the gray runoff of storm sewers, parking lots and drainage gutters. The clean roof water is directed into the nearby Class of 1918 Marsh, which acts as a detention basin, before entering Lake Mendota. All gray water from development is being diverted to a separate settling pond, reducing the amount of suspended solids entering the marsh and lake.
3. Infiltration Aides
   In 2005, three large rain gardens, totaling more than 40,000 sq ft in surface area, were installed adjacent to Willow Creek to absorb runoff from impervious surfaces, including streets, parking lots and roofs. The basins feature a variety of emergent sedges and rushes in their bottoms and an assortment of deep-rooted prairie plants along edges. During heavy rainfall, an overflow pipe directs water into a series of perforated pipes called infiltration laterals. In this process, runoff is cooled down in the pipes before being absorbed into the ground or entering the lake.

Leading the Way to Cleaner Waters

Looking ahead, UW-Madison plans to continue taking its commitment to storm water management seriously. In the future, a new artificial-turf marching band practice field will be equipped with 3-ft, stone-filled retention trenches running along its edges. The trenches will interrupt overland flow before it can enter the lake.

This is just one example of many new projects just over the horizon. UW is proud to be taking a leadership role in the preservation of local waters and setting an example for change.