The Louisiana Department of Wildlife and Fisheries (LDWF), in conjunction with the Grand Bayou Reservoir District, has scheduled a drawdown of Grand Bayou Reservoir (Red River Parish) for aquatic vegetation control, organic reduction, habitat improvement and structural maintenance along the shoreline. The drawdown is designed to reduce nuisance vegetation, improve habitat along the lake’s littoral edge during the fall and winter, and provide enough time for physical repairs.
The water control structure is scheduled to open on October 5, 2020, and the lake should dewater at a rate of 4-10 inches per day depending on inflow. The water level will be lowered to a maximum drawdown level of 7 feet below normal pool stage to a target level of 131.5 Mean Sea Level. The Grand Bayou Reservoir control gates are scheduled for closure on January 29, 2021, to allow the lake to refill for early-spring recreational activities.
During the drawdown, an estimated 2,000 acres of water will remain in open areas of Grand Bayou Reservoir. Boaters may still access the lake from Grand Bayou Resort, located on the Southwest side of the Hwy 784 Bridge. Caution is advised when on the water, as numerous obstructions that are normally not seen are present. Vessels will likely have to idle several hundred yards from the Grand Bayou Resort ramp before accessing deeper water.
This action is a necessary component of LDWF’s integrated management plan to control overabundant aquatic vegetation growth and to improve access for recreational activities. Periodic reservoir drawdowns have many benefits, including the recycling of nutrients and shoreline terrestrial plant growth that results in increased habitat. Also, phytoplankton and zooplankton abundances increase, resulting in better growth of young of the year fish. Reduced organic layers improve areas for spawning activity and spawning success of nesting fishes. Additionally, the lower water levels can concentrate forage fish, which in turn makes them more available and can increase the weight and health of game fish before spawning.