We do lots of silly things with water. Whenever it rains, we funnel a lot of it straight into the sewers without ever using it. We take perfectly good drinking water and flush it down the toilet. And, at least in some places, we fill ponds with tap water.
At least at Chicago’s Lincoln Park Zoo, that’s starting to change.
The Lincoln Park Zoo’s new Nature Boardwalk exhibit opened on June 24. It surrounds a 14-acre pond that has been transformed into a haven for native plants and animals. Once filled with tap water, the pond is now a naturalized basin that receives and holds rainfall, known once it hits the ground as “stormwater runoff” (which is what ponds are supposed to do).
“Water no longer flows into this pond continuously from Lincoln Park Zoo,” said Senior Vice President of Conservation Programs Steve Thompson. “We estimate that saves somewhere between 70 and 100 million gallons of water a year that was previously coming from the city’s water system.” Effective stormwater management also has lessened Lincoln Park Zoo’s contribution to Chicago’s combined sewer overflows during large storm events by managing more rain where it falls.
Before the Boardwalk, the pond not only was filled with tap water, but it also was constructed for recreation, rather than to fluorish as a native ecosystem. Concrete walls and a lack of graded shoreline detracted most wildlife from taking up residence. The shallower water meant “fish were unlikely to overwinter,” meaning stay in the pond through the winter, Thompson said. “It was prone to algal blooms,” he added. “Not a good habitat for wildlife.”
The pond’s rehabilitation has changed the area tremendously. Most of the concrete was removed and the pond deepened. “Our reimagining was to create a natural ecosystem,” said Thompson. With a shoreline, natural vegetation, and deeper waters, many of the wildlife now present came to the pond naturally. “The only thing we have stocked is fish,” said Thompson. In the heart of an urban environment, visitors can now enjoy a natural environment, including 13 species of dragonflies, fat-head minnows, blue gill, and the endangered black-crowned night heron.
The Lincoln Park Zoo’s Nature Boardwalk is only the newest of the zoo’s many water saving innovations. Seven green roofs manage stormwater and help to reduce energy consumption. Native plants, which have lower watering needs, represent 40 to 50 percent of the zoo’s garden plants. Many old water systems have been replaced with filtration and recirculation systems that significantly reduce the total amount of water used.
Why go to such lengths? As one of the city’s foremost educational and cultural institutions, “We were motivated to be an example,” said Thompson.
100 million gallons saved per year
Reconditioning the Lincoln Park Zoo’s 14-acre pond created a self-sustaining ecosystem that draws far less water from Chicago’s supply
50% native species
Lincoln Park Zoo estimates about 50% of their total plants are native species. Because of their deep-rooted growth and ability to stabilize soil, native plants have many great applications for stormwater management.
32% water use reduction since 1990
The City of Chicago has reduced its water usage by about 32% in the past 20 years – an impressive feat considering the population increased by 24%.
• Choose native plants. They tend to need less water, saving you time and money – and preserving the region’s water supply.
• Reduce stormwater runoff on your property. Take what steps you can to prevent rain from running off your property into the sewer. Rain barrels are a great start, especially when managed correctly. Rain gardens, permeable pavement, and rainwater harvesting systems also can help. Use CNT’s Green Values Stormwater Toolbox as a guide.
• Encourage your local leaders to be leaders. Urge your community officials to take a similar approach to the Lincoln Park Zoo, by managing stormwater and water consumption in local ponds, parks and natural areas. A great guide for communities can be found in the Model Water Use Conservation Ordinance, from the Chicago Metropolitan Agency for Planning.