Continuing their long-standing collaboration to enhance the overall health of Henderson Lake, and based on the Louisiana Department of Wildlife and Fisheries recommendations, the St. Martin Parish Government has scheduled a drawdown for Henderson Lake in St. Martin Parish to help manage invasive aquatic vegetation and improve fisheries habitat.
Due to the recent record-setting rainfalls in St. Landry and Avoyelles Parishes, and the resulting floodwater that was diverted into Henderson Lake through the Bayou Courtableau Drainage structure, water levels in the lake are still high, according to the Department of Wildlife and Fisheries. Because of these high water levels, the start date for the drawdown will not occur at the beginning of August as it has in the past, but will begin once the lake has reached pool stage, or 9.0 feet above mean sea level (MSL) at the US Geologic Survey (USGS) Lake Pelba gauge (https://waterdata.usgs.gov/monitoring-location/USGS-302020091435700).
Once the southern control structure gates are open, the lake will dewater at a rate of two to four inches per day until it reaches 3.0 feet below pool stage, or 6.0 feet MSL at the USGS Lake Pelba gauge. The drawdown will conclude on Monday, November 2, 2026, at which time the lake will be allowed to refill.
Houseboat owners are encouraged to take any necessary precautions as soon as possible. During the drawdown, boaters will be able to access the lake from the private ramps along the southern levee. Boaters should use caution as numerous obstructions will be exposed or may be present just under the water's surface. Boaters should also be cautious about potential interactions with Silver Carp as the lower water levels are conducive to those fish jumping around moving vessels.
In addition to the control of overabundant aquatic vegetation, the drawdown will benefit the lake's fish population by promoting a balanced predator-prey relationship, where forage fish are more available to predator species. The dewatering will improve the spawning habitat by promoting the decomposition, drying, and compaction of organic materials such as leaf litter and submerged vegetation.
Appropriate herbicide applications will continue during the drawdown period.
The Henderson Lake Waterbody Management Plan can be viewed at: www.wlf.louisiana.gov/resources/category/freshwater-inland-fish/inland-waterbody-management-plans.
