• E-mail
• Print
• Comment
• Font Size
• Digg
• del.icio.us
• Discuss article

Water Storage Plan Approved As Part of Everglades Restoration

Posted on: Thursday, 14 July 2005, 21:00 CDT

Jul. 14--South Florida water managers agreed Wednesday to finish building a water-banking well west of Boca Raton to help fully investigate a controversial, costly and still uncertain pillar of their Everglades rescue plan.

The South Florida Water Management District board approved spending $2.24 million to complete the project, which would pump water from the adjacent Hillsboro Canal 1,225 feet below the ground for storage.

The water would be closeted in myriad cubbyholes and larger voids that comprise a limestone formation called the upper Floridan aquifer. Theoretically, much of it would stay put and could be pumped back out to meet the needs of people or wildlife.

This subsurface reservoir of sorts would be the first of four contemplated pilot projects to explore the viability of building up to 333 such "aquifer storage and recovery" wells, including 30 near the west end of Lox Road, others west of U.S. 441 in Palm Beach County and 200 around Lake Okeechobee. Combined, the wells could squirrel away 1.7 billion gallons of storm water otherwise jettisoned to the sea to prevent flooding but at a price that accounts for one-fifth of the $8.4 billion Everglades restoration tab.

Cities already have employed the idea to build back-up water storehouses. They've built similar but smaller-volume, deep-storage wells, 1 to 2 million gallons a day versus the 5 million gallons a day per well called for under the Everglades project.

But in a 2002 study, the U.S. Geological Survey looked at 25 such systems and found a "spotty" track record at that time, according to agency hydrologist Ronald Reese. In fairness, a lot of those had only a few tests completed then and it was hard to tell how well they'd ultimately work, Reese said.

One well dug by Boynton Beach has been held out as a model of success, recovering 90-plus percent of the water it pumps underground, but others have had much lower recovery rates, or have developed glitches that include pumps disabled from siphoning in too much sand, he said.

One hope is that Everglades wells could store the fresh water for multiple years, but there's not a lot of proof to support that yet, said Robert Renken, another geological survey hydrologist.

"We really don't know how well they're going to store water over the long term," Renken said.

Environmental groups have differing opinions on the well idea, which eliminates water loss from evaporation and avoids the purchase of expansive pieces of floodable land.

Audubon of Florida supports conducting deep-well pilot projects.

Adamantly opposed, though, is the Florida Sierra Club, which sees the well idea as a technological gamble and another unnatural plumbing fixture for the Everglades, which already is reliant on pumps, gates and levees to function. It also could pose an environmental threat by harming Floridan water, a backup drinking source for the region, Sierra contends.

"We should not pursue a very questionable scheme," Sierra spokesman Jonathan Ullman said. "We know how to build reservoirs, there's a higher degree of safety and certainty with [those]."

Scientists have raised potential problems and issues to investigate, a key purpose of the pilot projects, water managers said. Among those: Will the fresh water pumped into the porous rock stay put long for a good recovery rate? Will the water sent into the wells liberate subterranean contaminants, such as arsenic, that could render the stored water useless? Will the pumping pressure fracture the aquifer rock, or shift patterns of ground water flow vital for other wellfields?

Peter Kwiatkowski, a lead project manager for the water district, said his agency shares some of the same concerns, but said "the best way to answer those questions is to put in the pilot projects and the let the data speak for itself."

The Hillsboro Canal well is partly in place. A 24-inch wide pipe was installed there in 1999, along with outer protective casings, during exploratory drilling to check the suitability of that location's geology.

New work would add a canal-bank inlet to pull water from the Hillsboro, filters and ultraviolet light to neutralize coliform bacteria and treat the water to primary drinking water standards, and a pump to shove it down into a containment area with clay roof to help seal it in place. The construction could be done in 9 to 10 months, and a two-year testing period would ensue, said water district senior hydrogeologist Richard Nevulis.

"It's definitely going to provide a lot of good information," Nevulis said of the well.

-----

To see more of the South Florida Sun-Sentinel -- including its homes, jobs, cars and other classified listings -- or to subscribe to the newspaper, go to http://www.sun-sentinel.com.

Copyright (c) 2005, South Florida Sun-Sentinel

Distributed by Knight Ridder/Tribune Business News.

For information on republishing this content, contact us at (800) 661-2511 (U.S.), (213) 237-4914 (worldwide), fax (213) 237-6515, or e-mail reprints@krtinfo.com.

Source: South Florida Sun-Sentinel

More News in this Category