Environmental Progress - Fall 2004

IEPA Works With Other Agencies to Rally Preservation and Management of Ancient Lake Chicago Shoreline Remnant in Calumet City

Bureau of Water staffer conducts tours at Superior Street Land and Water Reserve

Prompted by a request to the Agency for authorization to fill in a wet prairie in early 1995, Rob Sulski of the Bureau of Water in Illinois EPA's Des Plaines Regional Office, made the first of what would be many subsequent visits to the Superior Street Land and Water Reserve (formerly the Thornton Fractional High School Prairie) in Calumet City.

Sulski discovered what only a handful of earnest plant ecologists and native flora experts and enthusiasts had been privileged to enjoy before him - an ancient and breathtakingly significant Lake Chicago dune and swale remnant specific to Lake Calumet and only a smattering of Lake Michigan area sites.

Lake Chicago was formed 14,000 years ago, after the retreat of the Wisconsin glacier. As the glacier melted, water was dammed by the Tinley Moraine, forming a lake 45 miles long and up to 15 miles wide. The floor of this lake was very flat because of repeated wave action.

Thousands of years later, 90 percent of the Lake plain developed into Chicago and its surrounding suburbs. The lake water level lowered in two distinct steps. After the second lowering, the beach was located at the present day site of the Superior site. The repeated wave action created beaches and spits near the lake shore, which later, when the Lake completely disappeared, became ridges separated by shallow marshes. This ridge-marsh formation is the basis of Superior's dune and swale ecosystem.

Today, Superior contains one of the most diverse arrays of ecological communities in the Midwest, including wetland, sedge meadow, black oak savannah and wet, mesic, and dry prairie elements. It supports nearly 400 species of plants, shrubs, and trees; three Illinois endangered and 30 extremely rare species; and countless other wildlife in this single 34-acre site.

Not only is the Superior Street Reserve a diverse ecological terrain but also, of equal importance, a critical link in a larger complex of Greater Calumet habitats. It is contiguous with some high quality Commonwealth Edison property, the Sand Ridge Nature Preserve, and the Wentworth Prairie. It is also situated along the Burnham Green Way Trail corridor, linking Superior with the Burnham Prairie, the Calumet City Prairie, and the Shabbona-Green Lake Woods.

Unfortunately, the Superior Street Land and Water Reserve continues to remain a site at risk. Although the Illinois Department of Natural Resources (IDNR), with the assistance of some small grants, performs management work, and its "reserve" status protects it from development; other factors, such as off-road recreational vehicles and non-native invasive plants, continue to destroy and diminish Superior's quality.

The site is also an "orphan" — meaning it lacks a dedicated citizen steward group willing to rally and coordinate necessary site-preservation and management-work activities and this compounds the problem.

Hoping to plant seeds of volunteerism, Sulski has been giving tours of Superior for the past seven years to all who were interested, especially local residents.

Illinois EPA Governor's Environmental Corps interns, past and present IEPA and IDNR employees, Southeast Environmental Task Force members, and other groups have a growing appreciation for the significance of Superior. Over the last few years, based on a request from the City of Chicago's Department of Environment (DOE), more extensive annual weekend tours have been given in conjunction with DOE's Calumet Family Saturdays, a program that was conceived to attract broader attention to the Lake Calumet area's natural parcels.

At this point no one has taken on the site-stewardship position, but there are a number of residents making repeat group and unaccompanied visits. Sulski is optimistic there is someone with the same vision as the late, prominent Chicago area plant ecologist Floyd Swink, who considered Superior one of his favorite sites. Swink was able to grasp the significance of the Superior Street Reserve, and there are others who will discover that around every corner of the site, a myriad of worlds is giving glimpses of the region's rich land heritage.