The Trump National Golf Course in Virginia was cited this week for cutting down trees on the banks of the Potomac River, a protected area because of its vulnerability to flooding.
The county said the golf course cleared 31,000 square feet of land along the river, almost three quarters of an acre.
Phillip Musegaas, vice president of programs and litigation for the Potomac Riverkeeper Network, said one of the reasons permits are required for work along the river is that removing trees can increase the amount of sediment and debris that flows into the river when it rains and then travel to pollute the Chesapeake Bay.
"It's actually not good for their own property to clear cut trees like that," he told ABC News.
The county says its rule requiring a permit to alter the riverbank protects property along the river, included property downstream from where the trees are removed, according to a news release announcing the violation. Any plans to remove trees or pursue other changes to the land have to be reviewed and approved to ensure it won't cause any harm to the area.
The Washington Post first reported on the trees last week and county officials confirmed the violation on Wednesday.
Officials told the golf course to discontinue all work in the area until they apply for and receive the proper permits, or face a fine of hundreds of dollars for each offense per day.
The Washington Post reported the Trump golf course ran into similar issues in 2010 when it removed more than 400 trees to create an unobstructed view of the river for guests. The county rule that requires a permit to remove trees along the river was enacted after that work was completed.
The Trump Organization did not respond to an emailed request for comment.