Tampa Bay Surface Water Treatment Plant (Design-Build), BRANDON, FL
A new and sustainable source of clean water for its customers; professional installation of various advanced ἀltration, pumping, and other systems required for efficient operation of the new plant; storage areas for keeping chemicals used in the water treatment process; significant cost savings for the client and local municipalities; multiple industry awards in recognition of the project's value.
To diversify its raw water supply resources and develop a sustainable water supply system.
SCOPE OF SERVICES
In 1995, the Tampa Bay Water Authority (TBW) embarked on the $609-million Master Water Plan Configuration I, a program designed to reduce its reliance solely on ground-water and develop new water supplies. One major component of this program was the design, construction, and operation of a new 66-million-gallon-per-day (mgd) surface water treatment plant. For the plant construction project, TBW decided on the design-build-operate (DBO) project delivery strategy.
In late 1999, TBW awarded the contract - one of the largest water treatment DBO agreements in the nation - to the team of USFilter/CDM and Clark Construction Group/Poole & Kent. Poole & Kent was responsible for all process mechanical, HVAC, and plumbing work.
P&K's work included two high-rate flocculation/sedimentation basins to remove color, dissolved organics, and turbidity from the water. These units use a proprietary high-performance microsand-ballasted flocculation/sedimentation process developed to efficiently agglomerate and quickly settle suspended solids from the raw surface water. Special settling tubes that collect the clean supernatant for additional treatment down-stream further improve the efficiency of this process. The settled solids and microsand ballast are pumped to hydrocyclones, which separate the sand from the sludge. The recovered microsand is then recycled to the flocculation/sedimentation process.
In addition, the company installed:
- Coagulant and polymer storage and feed systems for the flocculation/sedimentation process.
- Two cast-in-place serpentine ozone contactor tanks with gas dispersion system mixer/contactors installed on the inlet to each tank. The mixers premix the ozone to ensure thorough mixing in the contactor tanks for primary disinfection of the treated water. Ozone is gen-erated on site with two ozone generators.
- Two two-stage rapid mixing tanks for mixing lime slurry, caustic, and filter aid into the process upstream from the ozone contactor
- Two two-stage rapid mixing tanks for mixing lime slurry, caustic, and filter aid into the process downstream from the ozone contactor
- Eight dual-media, biologically active gravity filters with air-water backwash
- A filration system with a filered efflunt rate-of-flow controller for each filter; a fiberglass washwater trough system for each filter; two filtered water clearwells, each with two finished-water vertical turbine transfer pumps; two vertical turbine filter backwash pumps; and two multi-stage centrifugal air blowers for the air-water backwash system
- Two lime storage silos for storage of pebble quicklime, each equipped with a lime slaker, slaked lime slurry tank, and lime slurry feed pumps and piping
- Chemical bulk storage facilities and feed systems for treatment process chemicals
- Two 95-foot-in-diameter gravity lime sludge thickeners and a thickened sludge pump station.
- Four lime sludge belt filter presses and a truck loading station for dewatering and hauling lime sludge
- A washwater recycle basin and return pumping system for storing and recycling filter washwater and gravity sludge thickener supernatant.
Poole & Kent completed this project on schedule and on budget. Since water produc-tion at this facility, which exceeds both state and federal standards, costs just 53.9 cents per 1,000 gallons, TBW estimates that its partnership with the contractor under this DBO agreement will save the Southwest Florida Water Management District and local basin boards who helped fund the project approximately $85 million over the life of the contract. This savings will ultimately be passed on to the ratepayers.
The project has won numerous awards, including the Build America Award - Municipal Utility from the Associated General Contractors (AGC), the Outstanding Masonry Proj-ect Award from the Masonry Contractors Association of Florida, the Florida Gulf Coast Chapter Award of Excellence from the Associated Builders and Contractors (ABC). In 2003, TBW won the Infrastructure Award from the National Council for Public-Private Partnerships (NCPPP). The project also won the 2003 Grand Prize for Excellence in Environmental Engineering by the American Academy of Environmental Engineers.
Tampa Bay Water (TBW) is a regional water supply authority, Florida's largest public wholesale water supplier, serving 1.5 million customers in Hillsborough, Pasco, and Pinellas Counties.