Relentless drought boosts desal

Tampa Bay Water officials are investigating the construction of up to two more desalination plants in Pinellas County.


St. Petersburg Times,
published June 2, 2001

Construction is only beginning on the region's first seawater desalination plant, but water officials are already contemplating two more.

Galvanized by more than two years of devastating drought, the board of Tampa Bay Water decided to jump-start the next round of new water projects, which are designed to shield the region from the effect of future dry conditions, allow for regional growth and reduce ground water pumping in environmentally stressed areas.

On Friday, officials indicated a clear preference that those projects include a second desal operation and an option for a third. Most of the sites under consideration are in Pinellas County.

Instead of waiting until midsummer, when they were originally scheduled to choose projects for the second phase of water development, the board members said at a workshop Friday they would make those decisions on June 11.

"Why wait?" asked Pinellas County Commissioner Susan Latvala, a member of the TBW board, which had just been told the timetable was extremely tight for new projects scheduled to be online by 2008. "Let's give ourselves some breathing room."

The board's determination to advance with water development as quickly as possible shifted the focus immediately to more desal. It also raised the possibility that TBW could eventually abandon plans for two controversial new well fields, Cone Ranch in northeast Hillsborough County and Cypress Bridge II in central Pasco. The projects have been sources of regional friction for years.

Pasco interests object to another well field in an area already damaged by overpumping. Hillsborough residents fear pumping Cone Ranch would damage wetlands and draw down the Hillsborough River, Tampa's principal source of drinking water.

If the board votes to proceed with Desal II, two areas will be explored for possible sites. The primary area is several miles to the north and south of the Pinellas/Pasco boarder on the Gulf of Mexico around the mouth of the Anclote River. The second is along the Tampa Bay shoreline of St. Petersburg from Feather Sound south to Pinellas Point.

"Why not build both?" said Chris Hart, a Hillsborough commissioner who sits on the water board.

"That gets us the water we need out to 2014 without the well fields."

The board could choose to do that, or it could choose between Anclote and southeast Pinellas and then look at an entirely different site for Desal III.

If the board wants a desal plant that will produce more than 10-million gallons of water a day, a site in the Anclote area is the more likely. Officials don't believe they can get permits for a larger plant on the bay directly across from Desal I in the Big Bend area of Hillsborough County.

That $110-million plant, scheduled to come on line in December 2002, will start construction June 25, but faces two legal challenges.

The Anclote area was considered during site searches for Desal I. It was controversial because of nearby pollution from a federal EPA Superfund site and because of concerns over salt discharges into coastal estuaries.

Both of those problems would be eliminated if Tampa Bay Water designed a desal project to draw water and discharge brine, the salt byproduct of desal, miles off the coast in the deep water of the gulf. It could also open the option of building a plant much larger than the 25-mgd facility now envisioned.

"If your intake and discharge are offshore, the sky's the limit," said David McIntyre of Parsons Brinckerhoff, TBW's desal consultant.

"If you're out in a totally marine environment, the discharges have the highest salinity, but the impacts are minimal. If you are in an estuary, you have many more environmental considerations."

However, he added, the offshore option is by far the more expensive.

Whatever the decision on June 11, the development of new water in the region is going to cost water customers.

Projects to which Tampa Bay Water is already committed, including Desal I, a new water treatment plant and reservoir, are projected to add $7.84 to the monthly bills of homeowners who use about 8,000 gallons of water a month.

The increase will not come all at once, but in increments, as water projects come on line.

If the Tampa Bay Water board should chose the most expensive options for the future, they would add $9.04 to monthly water bills, also in increments, out to 2014.

"What we're paying for is drought-proofing the region," said Jerry Maxwell, Tampa Bay Water general manager.

"That's expensive, but we don't want to go through the last two years again."