Public Works CIP Project Update

 

Lake Seminole Restoration Project

Project ID# 000157A

 

Project Location

Lake Seminole

 

Project Overview

Pinellas County is implementing a programmed Capital Improvement Project (CIP) to 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. The County issued a Notice to Proceed on November 19, 2018. The contractor has completed construction of the Dredge Material Management Area (DMMA). The next step is the actual in-lake dredging; this effort began in November 2019. The contractor completed dredging of the north lobe in May 2020 and the south lobe in October 2020. The dredging goal was achieved with over 915,000 cubic yards of muck removed during dredging. The contractor will remove the dredging equipment from the lake in January 2021. The DMMA will be allowed to settle for at least twelve months, prior to final restoration of the site.

 

Project Schedule

Schedule is preliminary and will be updated as the project progresses.

• Design and Permitting: August 2018
• Begin Site Work at Dewatering Area: November 2018
• Begin In-Lake Dredging Operation: November 2019
• Complete In-Lake Dredging Operation: October 2020
• Site Restoration Complete: March 2023

 

Notice to Local Boaters

Date of Notice: Aug. 20, 2019

Effective End Date: Oct. 20, 2022

 

RESTORATION DREDGING TO BE CONDUCTED

WITHIN LAKE SEMINOLE

 

Dredging Commence Date: Nov. 26, 2019

Dredging Completion Date: Oct. 20, 2022 (anticipated)

Hours of Operation: 24 hours per day (day & night)

Days of Operation: Monday-Sunday (7 days per week)

Name of Dredge Vessel North: Miranda Joe

Name of Dredge Vessel South Lobe: Jessie Marie Dredge

VHF Channels Monitored: Channels 16 & 68

Land Contact: Richard Styron, Project Superintendent, Phone: (252) 725-7246

Secondary Land Contact: Bret Sapp, Project Manager, Phone: (727) 798-0238

Pinellas County Contact: Rob Burnes, Project Manager, Phone: (727) 453-3149

 

Mariners are urged to use extreme caution in the area of dredging equipment (booster pumps, pipeline, dredge barge, etc.), transit at their slowest safe speed to minimize wake, and proceed with caution after passing arrangements have been made. Pipeline, work vessels, dredge barge, booster pump barge(s) and buoys will be visibly lighted and marked according to Coast Guard regulations and will be in the area until all work is complete. Floating and submerged high density polyethylene (HDPE) pipeline associated with the hydraulic dredging operations of the lake will be utilized. Be aware that configuration and location of equipment can change daily.

 

Additional Information

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.

 

Lake Seminole is a 684-acre hypereutrophic shallow lake located in the west central Pinellas County. The lake receives runoff from approximately 3,500 acres of urban land. The contributing watershed is almost entirely developed with residential and commercial land use dominating the landscape. Created in the late 1940s by damming off the estuarine backwater area of the Long Bayou. Lake level is maintained by weir located on the south end of the lake along the north side of Park Blvd. The lake and adjacent Lake Seminole Park provide many recreational activities including boating, fishing, bird watching, and a variety of other water activities.

 

The dredge portion of the Lake Seminole Restoration Project will improve water quality in Lake Seminole through the removal of nutrient-enriched (phosphorus and nitrogen) sediments that are contributing to elevated nutrients in the water column and persistent algae blooms. The removal of the sediments from the lake will also improve in-lake habitats by reducing the available nutrients for algae and vegetation growth. The dredged sediments will be deposited in a 20-acre settling area called a dredge material management area (DMMA) to dewater and consolidate. The DMMA will be adjacent to the eastern edge of the lake near 98th St. and 94th Ave.

 

Project Contact

Robert Burnes -- Project Manager
Public Works Environmental Management
22211 U.S. Highway 19 N., Bldg. 10
Clearwater, FL 33765
(727) 453-3149
rburnes@pinellascounty.org