Louisiana wildlife officials are lowering five lakes and one multi-lake complex this fall to check the spread of giant salvinia, a floating fern that has choked state waterways since the 1990s. Drawdown windows are now set at Lake Bistineau, Cheniere Lake, Henderson Lake, Lake Chicot, Grand Bayou Reservoir and the Saline-Larto Complex, with each waterbody working on its own schedule and target elevation.
The Cheniere Lake drawdown began Aug. 11 and is scheduled to end Nov. 15, lowering the 3,100-acre lake by four feet below pool stage while its six public recreation areas stay open at reduced water. Lake Chicot’s control structure opened Sept. 8, with dewatering targeted at 1.5 inches per day and a 3-foot drop below normal pool; the Chicot control gates are scheduled to close Jan. 4, 2027, and the surrounding Lake Chicot State Park covers 6,400 acres.
Henderson, a 5,000-acre lake, began drawing down Aug. 24 at 2 to 4 inches per day and will hit 3 feet below pool by Nov. 2, 2026. Grand Bayou Reservoir’s 2,700 acres began dropping Sept. 8 and will continue through Jan. 4, 2027, at 4 to 10 inches per day toward a 4-foot drop, leaving an estimated 2,100 acres in open water. Lake Bistineau, at more than 17,000 acres, has already been lowered 8 feet since its Aug. 12 drawdown began; the state Wildlife and Fisheries schedule pegs Bistineau’s maximum drawdown at 8 feet below normal pool with about 10,000 acres of water remaining, and roughly $514,000 in contracted herbicide applications across an estimated 4,900 acres of treated vegetation.
Biological control continues alongside the drawdowns. Nearly 50,000 giant salvinia weevils have been released into the Saline-Larto Complex; two separate releases totaling 48,380 weevils were spread across four parishes and five locations in the complex to establish over-winter populations. Detailed schedules, elevations and boat-launch impacts are posted on the state Wildlife and Fisheries lake pages.
