Midewin collects surface water from four perennial streams that flow in a west-southwesterly direction: Prairie Creek, Grant Creek, Jackson Creek and Jordan Creek. These creeks drain an area totaling about 126 square miles of the Upper Illinois River Basin. This area, called the Midewin watershed, lies entirely within Will County, Illinois.

Biologists use the abundance, distribution, and productivity of aquatic organisms as indicators of the health and biodiversity of a creek. These organisms are affected by variables such as competition, predation, siltation, water chemistry, nutrient supplies, impoundments, and flow characteristics. Physical and biological data were collected for the streams of the Midewin watershed during at least five different studies in the last four decades (Larimore et al. 1960-1964, Brigham et al. 1978, Illinois Natural History Survey 1993, Glass 1994, Ragusa 1996).

The following tables and excerpts from The Streams and Watersheds of the Midewin National Tallgrass Prairie - Planning, Restoration, and Management Strategies describe the streams of Midewin, their local watershed conditions, and provides a preliminary basis for stream management decisions.

The following tables are Adobe Acrobat files. If you do not have Adobe Acrobat Reader, you may download it for free from Adobe Site.

Table 1. Streams of the Midewin Watershed.
Table 2. Summary of Estimated Land Uses of the Midewin Watershed: 1997.
Table 3. Macroinvertebrates of Prairie, Jackson, and Grant Creeks.*
Table 4. Fish Species Recorded for Prairie, Jackson, and Grant Creeks*
Table 5. Results of Fish Surveys and IBI ratings for Prairie Creek.