Asea Brown Boveri (ABB) Desalination plant under construction in Perth, Australia
By Deirdre Conner Story updated at 12:09 PM on Friday, Apr. 24, 2009 EMAIL PRINT
No longer the land of unlimited water, Florida is setting its sights on drinking from the sea.
With one desalination plant operating in Tampa Bay and another in the works for Flagler County, the practice of turning seawater into fresh drinking water is drawing increasing attention. And this week, the St. Johns River Water Management District declared that a desalination plant has an almost-certain future in Jacksonville, too.
The water we use to drink and water our lawns currently comes from an underground aquifer - that's the case in almost all parts of Florida. But levels in the aquifer are declining as utilities pump more and more to meet growing demand.
For that reason, Central Florida communities are looking to tap the St. Johns River as a water supply, enraging downstream communities in Northeast Florida.
The strategy of de-salting seawater is often mentioned as an alternative. But although ocean water is plentiful, transforming it to tap water it isn't easy.
High-cost procedure
Desalinating and treating seawater can cost triple or more what it costs to treat fresh groundwater. And desalination poses its own environmental threats, something acknowledged even by activists concerned about taking water from the St. Johns River.
Although the water management district's executive director, Kirby Green, said it's almost inevitable that Jacksonville will need a desalination plant in the next 20 years, managers at JEA don't appear to agree.
Karl Hankin, JEA's water/sewer system manager, said Tuesday the company will use all other options before considering desalination, including searching for brackish groundwater to pump and treat, and increasing the number of people who use reclaimed wastewater on their lawns.
Most wastewater in Jacksonville is dumped into the St. Johns River, unlike in other parts of the state where more wastewater is reused.
"The ones we're really counting on for sustainable water supply is reclaimed water use and conservation," Hankin said. "Those yield tremendous opportunity with the lowest cost."
JEA also is considering the possibility of running another pipe under the St. Johns River to tap wells in the north and west part of the county to move water to the more populated south and east parts of the region.
But some counties that already make heavy use of reclaimed water and have used up their available groundwater have found themselves forced to consider desalination.
With dwindling groundwater resources, Flagler County is one. Cost estimates showed it would be potentially less expensive than piping water from the St. Johns River, miles away from the rapidly growing coastal community of Palm Coast.
The Coquina Coast Desalination Plant is only in the very early planning phases but has attracted a lot of partners, including St. Johns County. It has a vote on the Coquina Coast board, and county tax dollars have helped fund a study that is examining whether the plant should be land- or ship-based.
St. Johns County's utility department has a water rate structure that encourages conservation and recently started pumping brackish groundwater - which must be treated through a reverse osmosis process - to supplement limited supplies of fresh groundwater.
"We're not in a dire situation, but we may need it to augment our current plan," said Bill Young, St. Johns County's utility director. "It makes sense to be at the table early on."
Environmentalists such as Carl Matthaei of St. Augustine want to see as much scrutiny of desalination as there has been on withdrawing river water. Desalination requires a lot of energy, which gives the plants a big carbon footprint, and discharges millions of gallons of a briny concentrate that some call toxic.
The Coquina Coast project has been open to public comment, Matthaei said, but he worries it could threaten endangered species such as right whales and sea turtles.
St. Johns Riverkeeper Neil Armingeon, who has led the fight to stop withdrawals from the St. Johns River, said people are frequently asking him: What about desalination?
"Everyone's always looking for the panacea," Armingeon said. "The issues that we clearly have to talk about in relationship with desal is energy cost and what to do with the discharge."
Before looking to the sea, Armingeon said, utilities should do more to conserve.
"Reducing consumption is the only way we're going to make it work," he said.
An example in Tampa Bay
Nearly everyone who's anyone in water planning appears to have toured the Tampa Bay Desalination Plant, which touts itself as the largest seawater desalination plant in North America and provider of close to 10 percent of the area's drinking water. The plant takes seawater first used to cool an adjacent power plant, then desalinates it.
It also has been in a fishbowl. The Tampa Bay plant has been part model, part cautionary tale for other water managers interested in desalination. First conceived in the 1990s, the project was plagued with financial problems and delays. It only went to continuous operation in 2007.
Today, even at full operation, it is producing between 16 million and 20 million gallons a day, below its 25-million- gallons-a-day capacity. Still, it's a needed relief for the area, which is experiencing a drought so severe that homeowners have been ordered to stop watering lawns and the local water authority is facing hefty fines for over-pumping groundwater wells.
Water managers there have said they are considering expanding the desalination plant or building another one in the next 10 years, said Chuck Carden, director of operation and facilities.
Supporters of the Coquina Coast proposal aren't scared off by Tampa Bay's experience.
"We hope to learn from their mistakes," Young said. "Desalination would just be one part of a water supply plan. We think we're doing a responsible thing."
deirdre.conner@jacksonville.com, (904) 359-4504
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