Lake Seminole is popular destination for recreational activities. It is the county’s second largest freshwater lake.
CLEARWATER – Pinellas County Commissioners approved two items of business July 18 that moves forward work aimed at improving the water quality in Lake Seminole.
Considered as an “impaired waterbody” due to elevated levels phosphorous and nitrogen in the lake, the county has been working to improve the water quality since it began to decline in the late-1980s.
Millions of dollars have already been spent and millions more are needed to pay for the upcoming Lake Seminole Hydraulic Dredging Restoration Project. Dredging is expected to remove of 416 tons of nitrogen and 77 tons of phosphorus.
Commissioners approved a bid award of $668,670 to Waterfront Property Services for permit modification and other professional services for the project. In addition, they said yes to a funding agreement with Southwest Florida Water Management District, which has agreed to pay $8 million of the more than $18.66 million of the two-phase project.
Phase 1 is the time for permit amendments and design work, which will be done by Waterfront Property Services. Phase 2 is the actual dredging, plus dewatering and disposal of sediments from the lake.
Funding includes $8 million of Penny for Pinellas tax revenue, $8 million from SWFWMD, $5.2 million in RESTORE Act money, as well as other grant or funding opportunities, which staff is currently exploring.
Work on the project isn’t expected to start until Aug. 31 with modifications of permits scheduled to be complete by July 31, 2018. The actual dredging at the lake should begin by Aug. 31, 2018, and work won’t be complete until the end of 2023.
Lake Seminole is a described as a highly eutrophic waterbody, which means it is rich in nutrients and supports a dense plant population. When the plants decompose, it takes the oxygen out of the water and animal life dies. Dredging of the 684-acre lake would remove the decomposed plant materials.
Lake Seminole was created in the 1940s when a decision was made to build a dam on an arm of Long Bayou, a brackish water segment of Boca Ciega Bay. It is the second largest fresh-water lake in the county and a popular recreational destination.
However, it has been a constant battle to keep the water clean, keep the fish stocked and combat the growth of nuisance aquatic plants. In 1991, the county completed a diagnostic feasibility study ahead of a Watershed Management Plan adopted in 2004.
In 2005, the lake was lowered and the muck removed. Over the years, the county has built regional stormwater treatment facilities, implemented bypass canal treatment and diversion, done shoreline restoration, restored priority wetlands and installed a gauging station.
County officials say that the water quality of the lake is improving. Nitrogen and phosphorous levels are going down. Chlorophyll is decreasing. Water clarity is improving. But, the nutrient levels are still too high.
The dredging project is the No. 1 recommended method to try to reduce the levels and continue improving water quality.