February is a popular month for fishermen on the state’s busiest lake, 33,000-acre Barnett Reservoir near Jackson. Officials at Pearl River Valley Water Supply District, the state agency that oversees operations of the lake, urged boaters to use extreme caution on the water.
“The lake will be drawn down about 2 1/2 feet below normal all February, which will increase the number of obstacles near or at the water line,” said John Sigman, PRVWSD’s general manager. “It will also mean that only a few of our boat ramps will be open. Be careful launching and be extremely careful while running.”
Sigman said The Rez was lowered as part of the emergency action plan related to the outbreak of a sinister invasive plant species, giant salvinia. The plant was first discovered in the Pelahatchie Bay area in 2018, and PRVWSD and its partners have been battling it ever since.
Officials felt that it had eliminated most if not all of the plant in 2019 by using herbicides, burning and dropping the lake level to 296 from January to October. No Salvinia had been spotted for four months. Then, in October, the decision was made to raise the lake back to its normal elevation of 297.5, which could help expose any colonies that had survived. It was thought it would require several weeks if not months to achieve that rise.
“Unfortunately, it happened much quicker,” Sigman said. “We had an unseasonable heavy (4- to 6-inch) rain over a two-day period in October that pushed the lake all the way up basically overnight. We did not need that.”
Biologists found one surviving colony in an area where none had ever been spotted. By the time it was located, it had broken free from its base area and was being pushed by wind.
Workers succeeded in using oil booms to surround the location and contain the plant within 36 hours of its finding. The water had shot up so fast, however, that it is unknown if any of the highly mobile plant had escaped.
Sigman said actions were immediately taken to establish a new plan to fight that one area. Because the water around the island location is deeper, it was necessary to lower the lake another foot lower than in 2019 to 295.0.
“Our partners will use February at low water to fight this plant with fire and herbicide to eradicate what we can, and at the same time survey the entire Pelahatchie Bay area to see if any spread,” he said.
By deadline for this issue, no new areas of Salvinia had been discovered and the existing colony has been treated several times with herbicide.