A new federal proposal from the EPA and Army Corps of Engineers aims to limit Clean Water Act protections for wetlands, potentially affecting over two-thirds of Illinois' remaining wetlands. The rule codifies a 2023 Supreme Court decision, excluding seasonal wetlands from federal safeguards. Environmental groups warn of significant habitat loss, while industry supporters praise the clarity it provides.
The Environmental Protection Agency and Army Corps of Engineers announced the proposal last week, redefining "Waters of the United States" under the 1972 Clean Water Act. This change builds on a 2023 Supreme Court ruling that restricts protections to wetlands directly connected to larger, permanent water bodies like rivers and lakes, where the boundary is indistinguishable. Under the new criteria, wetlands must hold water during the wet season and maintain a surface connection to a major water body then, effectively barring seasonal streams and dry-period wetlands from coverage.
In Illinois, where wetlands have dwindled from over 8 million acres in the 1700s to just 10 percent today due to agriculture and development, the impact could be severe. A University of Illinois Urbana-Champaign study estimates that 72 percent of the state's roughly 700,000 acres of wetlands—about 504,000 acres—would lose federal protection, with the figure possibly rising to 90 percent depending on final wetness definitions. These ecosystems provide $419 million in annual flood protection for residents and support diverse wildlife, filtering water and storing carbon to fight climate change.
"We’re looking at up to 85 percent of the country’s wetlands losing their protected status under the Clean Water Act," said Andrew Wetzler, senior vice president for nature at the Natural Resources Defense Council. A 2025 analysis by the group projects 70 million of the nation's 84 million wetland acres at risk. Without federal permits required for development, wetlands could face unchecked filling or paving, according to Wetzler.
EPA Administrator Lee Zeldin defended the proposal, stating it "protects the nation’s navigable waters from pollution, advances cooperative federalism by empowering states, and will result in economic growth across the country." Zippy Duval, president of the American Farm Bureau Federation, added, "The Supreme Court clearly ruled several years ago that the government overreached in its interpretation of what fell under federal guidelines... We are pleased that it finally addresses those concerns and takes steps to provide much-needed clarity."
Robert Hirschfeld, director of water policy at the Prairie Rivers Network, noted, "The vast majority of Illinois wetlands do not have federal protection. The loss of the federal Clean Water Act means it is open season on wetlands." Chelsea Peters, a PhD candidate in wetland ecology at the University of Illinois and lead study author, confirmed, "We determined that about 72 percent of Illinois wetlands... no longer meet that criteria for continuous surface connection to relatively permanent waters in Illinois."
The proposal enters a 45-day public comment period, with potential finalization in the first quarter of next year. States like Colorado have enacted their own protections post-Supreme Court, but Illinois efforts have stalled.