Early homesteaders in Iowa took advantage of the rich soil in prairies to grow their crops, plowing the tall grass and straightening and dredging creeks and rivers. Thus, many of Iowa's estimated 6 million acres of prairie wetlands was drained. The discovery of the nutrient-rich soil in the wetland basins only increased the pace of drainage activity. Drainage districts and a network of tile lines have impacted large areas of wetlands. This high level of modification in what was once a natural hydrologic system has resulted in several unintended consequences, and the loss of many wetlands benefits.
Wetlands are nature's natural water filter.
They maintain and improve water quality by intercepting runoff as it moves through the wetland system. The organisms in wetlands can use or retain agricultural nutrients and process chemical and organic wastes. The fractive surfaces of wetland plants and slow-moving or still waters also settle out sediments eroded from uplands. Research indicates that a wetland environment increases the quality of water before discharging it into streams and creeks or before it percolates through the soil. Lush vegetation and abundant microbial life are characteristic of healthy wetlands.