Lake Apopka water quality project will use a 2,000-foot-wide, lake-bottom sump
The St. Johns River Water Management District has recently completed dredging to create a 2,000-foot-wide sump, or depression, on the bottom of Lake Apopka. The sump is designed to help collect nutrient-laden sediment and improve water quality in the lake.
“Our focus remains centered on projects that bring us closer to our goal of restoring the lake’s ecosystem,” said St. Johns River Water Management District Executive Director Dr. Ann Shortelle. “Improved water quality provides conditions that are allowing native submerged plants to recolonize the lake’s bottom. As these plants expand, they will provide the habitat necessary for the recovery of the lake’s historic bass fishery.”
This is the first time a sump has been dredged in Lake Apopka. The sump, which is about 2,000 feet wide with a maximum depth of about 5 feet, is expected to collect about 500,000 cubic yards of nutrient-laden sediment. That amount of sediment would be enough to cover a 100-acre area at 3 feet high.
The project is unique from previous dredging projects because the lake-bottom sump will collect sediment over time. District staff will monitor the accumulation in the sump, and maintenance may be scheduled to remove newly accumulated sediment from the sump. Collecting and eventually removing the material is expected to reduce turbidity in Lake Apopka and help improve water quality.