In 2001, The Conservation Fund and the Milwaukee Metropolitan Sewerage District (MMSD) launched a pioneering flood management program, Greenseams®, to protect important open spaces in the metropolitan area. Greenseams purchases land and conservation easements from willing landowners in the Milwaukee, Menomonee, Oak Creek, and Root River watersheds where major suburban growth is expected to occur. Properties are chosen for their proximity to water, their water-absorbing soils, floodplain and wetland features, environmental corridor and natural area designations, and their connection to public spaces.

Our Accomplishments

Since the program’s inception, we have protected nearly 150 properties, preserving roughly 5,000 acres of flood-prone land within greater Milwaukee. This area includes 28 communities and 1.57 million people.

In 2017, Greenseams protected a 78-acre property that connected formerly preserved lands as part of the program, providing 270 acres of wetlands, wooded swamps, and upland buffer surrounding Lake Twelve for public use. The Lake Twelve complex is part of a larger Wisconsin Department of Natural Resources prioritized project area and includes a 13-acre property with a public boat launch on the lake provided by Ozaukee Washington Land Trust.

As identified by the Southeastern Wisconsin Regional Planning Commission, this natural area provides some of the most significant pre-European settlement open space in southeastern Wisconsin. By permanently protecting the Lake Twelve complex, 270 acres of continuous habitat is available to endangered, threatened, and rare plant and animal species in the region. The protected lands along Lake Twelve also provide natural storage for rain and snow melt, protecting communities downstream.

A partnership with the U.S. Fish and Wildlife Service Partners in Wildlife, the Wisconsin Coastal Management Program and the North American Conservation Wetlands Act is also helping restore many of the Greenseams properties to their native wetland, prairie and forest habitats. To date, the partners have planted 113,537 trees and restored over 760 acres of previously unproductive agricultural lands. Once restored, these properties absorb more rain and snow melt, which slows water flow into the City of Milwaukee. They also act as buffers which filter out pollutants and increase water quality.

Why This Project Matters

Back-to-back storms in 1997 and 1998 resulted in millions of dollars in property damage throughout the region. The Greenseams program was created to ensure that kind of devastation doesn’t happen again. By protecting and restoring wetlands—nature’s sponges—we are creating an area that can hold an estimated 1.3 billion gallons of water (about 1,970 Olympic-sized swimming pools). With the Greenseams properties open to the public, we are providing residents and visitors with the experience of being outdoors in natural settings, creating a sense of community, and improving public health and happiness.

Learn More


Greenseams photo gallery



Greenseams: Green Infrastructure In Milwaukee, St. Nikolas 




Success Of Greenseams

This video—featuring the Fund's Peg Kohring—explains how this innovative program is on the cutting edge of the green infrastructure movement. Video produced by Milwaukee Metropolitan Sewerage District.



What Is Green Infrastructure?

Do you know what green infrastructure is, really? Watch our video to find out what people think of green infrastructure and learn from the Fund's Will Allen exactly what we mean when we use the term. Video by The Conservation Fund.