Skip to content

Vacant Lots Create Cleaner Water

By converting abandoned properties into bioretention gardens, Detroit is turning urban blight into attractive, all-natural water-filtration systems

Community leaders, residents and students celebrate the transformation of a vacant lot into a biorention garden in Detroit, Michigan

Photo courtesy University of Michigan School of Natural Resources and Environment

Garden project partners, community leaders, neighborhood residents and students celebrated the transformation in 2016 of a vacant lot into a garden specially designed to capture rainwater and runoff.

More than one in three Detroit properties, nearly 140,000 in total, were foreclosed in the decade leading up to 2015, The Detroit News has reported. That's the equivalent of more empty, abandoned or torn-down homes in Detroit than there are houses in all of Buffalo, New York. It's an eerie streetscape, popular with horror filmmakers and macabre tour guides.

But some residents and advocates for Detroit's renewal are seeing green — not red — in their altered landscape. More specifically, through a partnership between the University of Michigan and the city, four Bioretention Gardens have been built in vacant lots on Detroit's west side. While beautifying the neighborhood, the gardens improve water quality in the region. 

"The fact that the city needs to demolish thousands of properties turns out to be an opportunity for the city to also clean storm water."

— Joan Nassauer, professor, University of Michigan School for Environment and Sustainability

Benefiting the bioretention recipe are the gaping holes produced when the city digs out the basements of abandoned homes. By filling those pits with a 2-foot layer of gravel, then 30 inches of engineered soil, followed by flowering shrubs and perennials, landscape architects have created natural water filtration systems that can invisibly capture and gently percolate up to 1.2 million gallons of storm water each year.

The neighborhood looks brighter, but the benefits go beyond the block.

In Detroit, untreated water from residential toilets flows through the same pipes as rain or storm water to the city's treatment plant. In downpours, the system can get overwhelmed, and untreated sewage can enter the River Rouge, which flows into the Detroit River, which empties into Lake Erie. By decreasing street runoff, the new gardens lessen the chance of a sewage spill into the lake.

"Projects like these are going to be extremely important as we move forward in the city," says Palencia Mobley, deputy director and chief engineer at the Detroit Water and Sewerage Department (DSWD). "They allow us to make use of vacant land and make it more productive, while at the same time eradicating blight."

The construction of the gardens, which depended on $500,000 from the DWSD and $285,000 from the University of Michigan Water Center, is only a start. Over the next years, researchers will assess how well the gardens work. By 2025, says Nassauer, there will be most likely be "hundreds of gardens."

This article is an excerpt from the "Public Places and Outdoor Spaces" chapter of the AARP book Where We Live: Communities for All Ages — 100+ Inspiring Ideas From America’s Community Leaders. Download or order your free copy.

Reporting by Mary Ellen Flannery | Page published October 2017 

You May Also Like

Our Free Publications!

See the complete list at

Follow Us

Contact Us

  • Email AARP Livable Communities at

  • Ask about the AARP Livability Index by completing this online form.

  • AARP Members: For questions about your benefits, AARP The Magazine or the AARP Bulletin, visit the AARP Contact Us page or call 1-888-OUR-AARP (1-888-687-2277).