Washington State Uses AI Tool to Map Wetlands After Federal Rule Changes

Washington state agencies and researchers developed a machine learning tool to locate wetlands that may lose federal protection under a November 2025 EPA definition. The definition limits federal jurisdiction to wetlands with surface water during the local wet season or that connect to year-round flowing water bodies.

The change followed the 2023 Supreme Court decision in Sackett v. Environmental Protection Agency, which required continuous surface connections to larger waters. EPA Administrator Lee Zeldin stated the prior definition had been used to expand federal authority over farmers and landowners.

The National Wetlands Inventory relies on aerial and satellite imagery reviewed by human analysts. Researchers said the inventory misses many small or seasonally dry wetlands, especially in eastern Washington where wetlands can shrink or disappear during summer months.

Dense forest cover in western Washington also obscures wetlands from aerial views. Amy Yahnke, senior wetlands scientist at the Washington Department of Ecology, said a better method was needed to identify wetlands in forested areas before they lose potential protections.

Halabisky at the University of Washington and Dan Miller at TerrainWorks created the Wetland Intrinsic Potential tool. The system analyzes slope, concavity, and greenness data to assign a probability that any given location contains a wetland. Connor Racette, environmental and geospatial specialist at the Washington Department of Ecology, said the tool has been applied in the Puget Sound region to update wetland boundaries and in Spokane County through the Voluntary Stewardship Program since June 2025.

Jacob Taylor, who coordinates the program, said it helps farmers identify areas that may function as wetlands on smaller operations. The tool is intended to support both conservation planning and land-use decisions by agricultural and development interests.