The main goals of the Lake Seminole Restoration Project are to reduce nutrient inputs into the lake, remove existing in-lake nutrients, and restore wetland and upland areas adjacent to the lake to improve in-lake water quality, ensure healthy fish and wildlife populations, and maintain recreational uses.
The project’s design and permitting process began in August 2018. Pinellas County issued a Notice to Proceed on November 19, 2018 and work commenced on the dredge material management area (DMMA). The DMMA is located adjacent to the eastern edge of the lake near 98th St. and 94th Ave N., across from Osceola Middle School.
Lake Seminole, the second largest lake located in Pinellas County, is a 684-acre shallow lake that receives runoff from approximately 3,500 acres of urban land. The lake was created in the late 1940s by damming off the estuarine backwater area of the Long Bayou. The water level is maintained by the spillover located on the south end of the lake along the north side of Park Blvd.
The runoff of nutrients, from the surrounding watershed area, has led to excessive quantities of organic sediments. The dredged sediments will be deposited in the 20-acre DMMA settling area. The in-lake dredging is anticipated to begin in August 2019
This Capital Improvement Project (CIP), costing in excess of $18 million, will remove approximately 900,000 cubic yards of accumulated organic sediment causing water quality and habitat degradation. The removal of the organic sediments, based on pre-construction sediment sampling, is expected to eliminate 54 tons of total phosphorus and 311 tons of total nitrogen from the lake and reduce nitrogen loads by an estimated 56% to Long Bayou and Boca Ciega Bay.
Material from the lake will be hydraulically dredged with a Ellicott swinging cutterhead dredge. At the longest length, the sediment will be pumped through 11,000 feet of temporary pipeline to shore where the material will be dewatered and disposed. The cleaned water will be returned to the lake.
The hydraulic dredging will begin in the north part of the lake progressing south toward Park Boulevard. The dredging is expected to complete around December 2021.
The sediment will eventually form a 15-foot high berm that will be topped with sand and be made available for new uses.
Over $8 million for the project came from the Penny for Pinellas and another $8 million came from the Southwest Florida Water Management District. The State of Florida contributed $1.5 million and the reminder, approximately $900,000, from the Restore Act.
Gator Dredging, headquartered in Clearwater, Florida was contracted for the dredging project.
The project is slated to be fully complete in March of 2023.