The Tampa Bay Seawater Desalination Plant provides a drought-proof, environmentally sound drinking water supply to the region.
Tampa Bay Water bought out the private developer and took over operations of the Tampa Bay Seawater Desalination Plant in 2002. In March 2003, the facility began using seawater to provide a sustainable, environmentally friendly, drought-proof supply of drinking water for Tampa Bay Water member governments’ utility customers. It is the largest seawater desalination facility in North America. Although the plant produced some water from March 2003 to May 2005, deficiencies in the plant design required Tampa Bay Water to shut down the plant in June 2005 and select a contractor to fix the deficiencies and operate the plant long-term.
Seawater Desalination Process Trains
In November 2004, Tampa Bay Water’s Board selected American Water-Pridesa to remediate the facility and operate it long-term. The plant went offline in June 2005; remediation construction began in November 2005. American Water-Pridesa completed construction in Spring 2007, after which the plant went through started up, tested and refinement of various processes. Additional work was conducted to improve sand filter and diatomaceous earth filter effectiveness and efficiency.
The remediated plant has passed an extensive acceptance test, which concluded Nov. 7. During the test, the plant ran for 14 days to prove performance at 25 million gallons per day (mgd) and at maximum capacity of 28.75 mgd.
- The Tampa Bay Seawater Desalination Plant is designed to produce up to 25 million gallons per day, and can accommodate an expansion to produce up to 35 mgd in the future.
- Plant modifications included overhauling the pretreatment process to correct inadequate screening and filtration as well as deficiencies in the reverse osmosis and post-treatment processes.
- At full capacity, the Tampa Bay Seawater Desalination Plant provides the Tampa Bay region with nearly 10 percent of its drinking water supply, making it the largest reverse osmosis (RO) seawater desalination facility in North America.
- The cost of water produced at the plant is expected to be competitive with other similar-sized plants operating around the world.
- The desalinated water is blended with water from other, less expensive water supply sources such as groundwater, making this alternative supply more affordable for member governments and consumers.
- The 30,000 square-foot seawater desalination plant is located on 8.5 acres of Tampa Electric’s Big Bend power plant in Apollo Beach. The facility uses reverse osmosis to extract high-quality drinking water from the saltwater in Tampa Bay.
- The concentrated seawater left over from the desalination process will not significantly increase Tampa Bay’s salinity because it is diluted in up to 1.4 billion gallons per day of power plant cooling water, a 70-to-1 dilution ratio. Monitoring during the plant's first year of operations showed no measurable changes in salinity, even when the plant was operating at maximum capacity.
- The
initial cost to build the reverse osmosis plant and a nearly 15-mile pipeline was approximately $110 million. However, the plant required significant remediation throughout, which brought the total capital cost of the project to approximately $158 million, including membrane replacement.
- Under the Partnership Agreement, the Southwest Florida Water Management District will reimburse Tampa Bay Water $85 million of the plant’s eligible capital costs in installments over the next 18 months. The Partnership Agreement earmarks locally collected ad valorem taxes to offset the cost of alternative water supply development.
