A proposed federal change to which waterways and wetlands qualify for protection under the Clean Water Act could affect communities across western North Carolina, including Charlotte, Lake Wylie, Gastonia and parts of the High Country. The Environmental Protection Agency and U.S. Army Corps of Engineers opened a public input period in September on a revised definition of “waters of the United States,” or WOTUS. The agencies said the proposal is intended to align federal rules with the U.S. Supreme Court’s 2023 decision in *Sackett v. Environmental Protection Agency*. The comment deadline is Friday, Oct. 9. EPA Administrator Lee Zeldin said the administration wants a definition that follows the law and reduces regulatory uncertainty. Environmental advocates argue the proposed approach could remove too many wetlands and streams from federal oversight, leaving decisions increasingly to states. Erin Carey, deputy director of the North Carolina Sierra Club, said the proposed changes could put more than 80% of the nation’s wetlands at risk of pollution or destruction. She contends the proposal goes beyond what the Supreme Court ruling requires. The potential local consequences extend beyond habitat. Wetlands can absorb and slow stormwater, and Carey said their loss amid Charlotte-area development may contribute to flooding in neighborhoods such as Oakhurst and to road closures during heavy rain. She also pointed to wetlands and other natural systems upstream of the Catawba River, a source of Charlotte-area drinking water, as important to water quality. Wetlands also support fish populations, Carey said, because many fish begin their life cycles in those habitats. That makes the proposal a concern for anglers and outdoor businesses as well as residents worried about flooding and clean water. A Natural Resources Defense Council map estimates that potential losses of federal protections could reach areas including Charlotte, Lake Wylie, Gastonia, Lincolnton, Morganton, Hickory, Old Fort, Pineola and Blowing Rock. The organization’s maps show both lower- and higher-impact scenarios; they are estimates, not a final determination of which specific waters would lose protection. Environmental and outdoor groups, including the Sierra Club, are gathering public comments ahead of the federal deadline. The agencies will consider input as they develop a final rule.