It’s National Wetlands Month, and in celebration of these important ecosystems, we are highlighting a few of the major wetland restoration initiatives that Openlands has taken part in in the Chicago region. Wetlands are areas where water covers the soil or is present either at or near the surface of the soil all year or for varying periods of time during the year. Rivers, lakes, streams, marshes, swamps, and bogs are all categories of wetlands that play an important role in our region’s ecology, as they collect water and minimize flooding, enhance water quality, control erosion, sequester carbon, and provide a home to at least one third of all threatened and endangered species. Unfortunately, due to development and major infrastructural changes like the reversal of the Chicago River in the 1900’s, Cook County has lost 40% of its wetlands since the 20th century. Without wetlands, our region experiences increased flood and drought damage, nutrient runoff and water pollution, and shoreline erosion. The loss of wetlands has also triggered a decline in wildlife populations.
The history of the Chicago region is a history of wetlands. Before the city was built into the booming metropolis it is today, much of the region existed as wet prairie, sedge meadow, and marsh. In fact, the name Chicago is derived from the Miami-Illinois word shikaakwa (“Stinky Onion”), or Nodding Onion, which is an odorous wetland plant native to the region. Chicago was built on a wetland that has since been filled. In both the city and in rural areas, in order to allow for development and farming, water was removed by installing drain tiles, which is a series of pipes made out of clay (now pvc) that drain water. Drain tiles move soil water to streams or drainage ditches and lower the water table, turning wetlands into dry lands.
While the draining of the wetlands in the Chicago region allowed for the development of a great metropolis, we now know that in order to protect our local ecology, wetland restoration is necessary for the future sustainability of our region. Wetland restoration is a nature-based solution to climate change and an essential part of protecting wildlife.
Openlands’ part of major wetland restoration projects spans the region from Hackmatack National Wildlife Refuge down to Midewin National Tallgrass Prairie. In Cook County, Openlands partnered with the Forest Preserves of Cook County and the U.S. Army Corps of Engineers to restore wetlands and their surrounding upland habitat at Tinley Creek and Bartel Grasslands as part of the O’Hare Modernization Mitigation Account (OMMA). This project involved restoring around 900 acres of land owned by the Forest Preserves and an example of how through partnerships like this, taxpayer investments are extended for maximum impact. According to Linda Masters, Openlands’ Restoration Specialist, a majority of Openlands’ wetland restoration at these locations involved identifying where drainage tiles were installed, then disabling them in order to raise the water table and allow for the wetlands to reestablish themselves. Tinley Creek and Bartel Grasslands exist on flat geographies that used to be under a glacial lake until it drained to form lake Michigan. In order to later transform that wet land into farmland, drainage was required, meaning drainage tiles were installed under the ground .
The OMMA partners hired Huddleston McBride Land Drainage Company to assess the landscape, dig trenches to find the underground drainage tiles, then create maps of all the tiles. Valves were then installed to manipulate water levels and raise the level of the water table. According to Linda, Openlands has taken a “passive” approach to re-establishing hydrology, meaning that for the most part, nature is allowed to do most of its own work. However, the valves are occasionally manipulated if the land is too wet and is at risk of flooding, as that puts nearby development at risk. Along with disabling drainage tiles, Openlands removed introduced trees that were planted at both Tinley Creek and Bartel Grasslands post-farming. While Openlands is normally a proponent of tree planting, in this case, both landscapes were prairies before settlement , and the removal of trees allowed them to return to their natural prairie condition.
According to Linda, wetland restoration is essential for the health of both infrastructure and wildlife. Rather than creating hard surfaces like concrete that drain water quickly to rivers and cause flooding downstream, wetland restoration keeps water where it falls , making the land into a sponge. Wetlands also create habitat for animals that are adapted to living in or near water. Due to the drainage of our region’s wetlands, we have lost wading birds and waterfowl that have nowhere to go when wetlands disappear. By restoring wetlands, habitat is recreated that welcomes back the wildlife native to our region, maintaining the biodiversity of our region necessary to keep our ecosystems healthy and functional.