Monroe County and two environmental groups filed a lawsuit to stop the implementation of a forest management plan for Hoosier National Forest they believe will pollute Lake Monroe, a major drinking water source for the area.

Monroe County’s Board of Commissioners and Environmental Commission, along with the Hoosier Environmental Council and the Indiana Forest Alliance filed the suit to stop the U.S. Forest Service’s Houston South Vegetation Management and Restoration Project until alternative plans are considered.

The plan calls for the harvest of thousands of acres of trees and herbicide treatment in a part of the Hoosier National Forest located in the northwest corner of Jackson County near Houston, Indiana.

In the lawsuit filed in U.S. District Court in New Albany, county officials and the groups said many of the activities called for in the plan will take place on “steep slopes with highly erodible soils,” that would pollute streams that flow into Lake Monroe, the water source for more than 145,000 people.

The Monroe County officials said they repeatedly raised the issue in comments and objections and requested alternatives that would better protect the environment, but the Forest Service denied the plan would adversely affect the environment and Monroe County residents.

“After nearly 18 months of commenting, asking for key reports, and objecting to this project and the U.S. Forest Service’s dismissal of all the important concerns, Monroe County and the plaintiffs were left with no other recourse but to file this suit,” said Monroe County District 2 commissioner Julie Thomas in a press release.

Thomas and other county officials submitted comments about the plan, saying they were concerned about degradation to the lake’s already threatened water quality due to algae caused by sedimentation and other factors.

Some algae can release toxins that have harmful effects on humans, kill pets and livestock and impair drinking water supplies.

The Forest Service’s responded to the commissioners’ concerns about runoff pollution contributing to algae growth by stating that site-specific soil and water effects were already analyzed in a 2019 report.

The report concluded the project could directly affect water quality through local erosion and sedimentation and cause point-source contamination from equipment fluids and herbicide spray. However, it was restricted to the boundary of the South Fork of Salt Creek, one of four watersheds feeding into Lake Monroe and did not analyze the management plan’s effect outside that boundary, or any alternatives presented by Monroe County officials.

The report said the South Fork Salt Creek watershed was set as the boundary because it would be impossible to distinguish the project’s impact from the effects of other land-use activities in the other watersheds.

The lawsuit said the omission of the impact on the other watersheds feeding into Lake Monroe violates the National Environmental Policy Act, a federal law that requires federal agencies to assess the environmental effects of proposed federal actions prior to making decisions.

“The U.S. Forest Service has seemed hell-bent on doing this project regardless of its dramatic impact on people, wildlife and the forest ecosystem in general,” said Jeff Stant, executive director of the Indiana Forest Alliance. “We’re taking a stand to show that refusing to consider alternatives is against the law.”