The Illinois Natural History Survey (INHS) Wetland Science Program performs biological surveys and wetland delineations and conducts studies of mitigation wetlands, wetland soils and plant and animal communities.  

The Wetland Science Program works with state agencies to identify, protect, maintain, and restore wetlands in Illinois.  A primary partner is The Illinois Department of Transportation (IDOT), who has supported wetland surveys by INHS since 1987.  The Wetland Science Program helps IDOT remain compliant with federal and state wetland protection laws by identifying and delineating wetlands in the vicinity of proposed transportation projects. Our soil scientists, botanists and GIS specialists delineate wetlands based on features of soils, vegetation and hydrology, following procedures outlined by the U.S. Army Corps of Engineers.  Since 1987 we have investigated over 10,000 potential wetland sites in Illinois.  We maintain a long-term database of these wetlands, including site plant species lists and wetland community type.  This database has been used for investigations into such questions as long-term changes in non-native invasive plant species and increased presence of halophytes (salt tolerant plants) due to de-icing measures for seasonal highway maintenance. The Wetland Science Program also assists IDOT in locating sites that are appropriate for wetland restoration.  When impacts to wetlands are unavoidable, IDOT attempts to offset these impacts using created or restored wetlands near the impacted site. 

After restoration, we work with the Wetlands Geology Section at the Illinois State Geological Survey to monitor these sites and report on progress toward restoration objectives.  Much research has been published on these sites by faculty and students at the University of Illinois Urbana-Champaign and beyond. This research has helped improve our understanding of the processes behind wetland restoration and best practices for attaining restoration goals.

Wetlands provide recreation, flood control, and pollution reduction as well as vital food and habitat to plants and animals. The combination of dynamic water levels and high nutrients provides an enriched ecosystem that feeds many small animals, such as aquatic insects, shellfish, and small fish, some of which are food for larger predatory fish, reptiles, amphibians, birds, and mammals. About 35% of the nation’s threatened and endangered species depend on wetlands in some way.

While wetlands are some of the most important resources we have, they are also some of the most endangered habitats in the world. Illinois has lost more than 85 percent of its wetlands since the time of European settlement. Wetlands are threatened by development, pollution, and exploitation. It is imperative that we preserve, protect, and restore our remaining areas. Documenting existing wetlands, monitoring and advising on wetland mitigation measures, educational outreach, leadership and activity in professional societies are some of the ways that staff in the INHS Wetland Science Program contribute to wetlands and society.