State Parks has announced these new requirements for all trailered or motorized vessels:
Effective April 14, 2025, Folsom Lake and Lake Clementine will be closed to all trailered or motorized vessels. All boats wishing to launch into Folsom Lake or Lake Clementine are required to go through a mandatory 30-day quarantine.
After May 14, 2025 all trailered or motorized vessels entering Folsom Lake or Lake Clementine will be required to have a quarantine, and/or decontamination seal intact and verified prior to entering the water.
Also from State Parks:
Rather than close Folsom Lake to recreation boating, Reclamation and State Parks are opting for a prevention program. This action is necessary as a golden mussel infestation at Folsom Lake could cause substantial damage not only to the ecosystem but could also impact the power generation and water delivery systems at Folsom Dam and Reservoir.