Written by John-Luc Richmond
When you think of Indiana, wetlands might not be the first thing that comes to mind, but the state was once home to one of the most extensive network wetlands in the United States. The Grand Kankakee Marsh, often called the “Everglades of the North,” covered over 500,000 acres in northwest Indiana and was renowned for its extraordinary biodiversity, supporting wildlife such as bald eagles, whooping cranes, bears, wolves, beavers, salamanders, and snapping turtles.
Unfortunately, this vast wetland—and most of the approximately 5.6 million acres that once covered about 24% of the state—was drained during the 19th and 20th centuries, primarily to make way for agriculture. While protecting the remaining wetlands in Indiana is essential, the development of constructed wetlands presents an exciting opportunity to restore some of what was lost, while also improving water quality, soil health, and agricultural resilience across Indiana.
Constructed Wetlands
A constructed wetland is a manufactured area designed to work like a natural wetland. Its main purpose is to clean water—usually from household drains, farms, or stormwater runoff—by using natural processes. As water flows through the wetland, soil, plants, and helpful microbes work together to trap dirt, break down pollutants, and absorb excess nutrients, helping to improve water quality.
To build a constructed wetland, you usually start by choosing a low-lying area where water naturally collects, such as a drainage ditch or the edge of a field. The area is dug out and shaped with gentle slopes to help water flow and prevent erosion. Then, layers of gravel, sand, or soil are added to help filter the water. Finally, native wetland plants are planted, which play a key role in soaking up nutrients and providing habitat for beneficial organisms. Constructed wetlands can fit well into farmland because they make use of unused or hard-to-farm areas, like low spots or field edges.
Benefits of Constructed Wetlands on Farmland
Constructed wetlands, dispersed within and surrounding agricultural fields, have a multitude of benefits, such as:
- Enhanced soil health and nutrient cycling by capturing nutrients from fertilizer runoff, such as nitrogen and phosphorous, which can threaten safe drinking water and cause algae blooms that can kill aquatic animals and plants.
- Reduction of soil erosion and flooding by slowing down and storing water during heavy rainfalls.
- Increased habitat for birds and pollinators, especially when native species are planted, which create a biodiverse and healthy ecosystem.
Getting Started
The following resources provide further information on examples of constructed wetlands on farmland in the Midwest:
Harnessing Nature to Filter Agriculture Runoff in Illinois | TNC
Smart Wetlands — The Wetlands Initiative
Growing Wetlands to Protect Rivers – and the Future of Agriculture
If you’re interested in building a constructed wetland on your own land, a good first step is to identify areas where water naturally collects or runs off—such as field edges, low spots, or drainage ditches. Start small, and consider working with local conservation groups, extension offices, or soil and water conservation districts, many of which offer technical assistance or funding support for these types of projects. With proper planning and native plant selection, even a small constructed wetland can make a big difference for water quality, wildlife, and the long-term health of your land.
Your local County Soil & Water Conservation District (SWCD) can help with the planning process and potential funding to assist in the construction of a wetland.
Categories: Sustainable Agriculture, Wetlands