Monday, July 15, 2002

Reservoirs losing longtime appeal
States seek other options to ensure water supply

By Dave Williams
Times-Union staff writer

ATLANTA -- Last year, Georgia hired a reservoirs coordinator to oversee a system of regional reservoirs in the northern half of the state.

To Alison Keefer, that job title is a misnomer.

"The implication is the only option on the table is building reservoirs,'' she said. "Reservoirs were the obvious first choice 10 years ago. ... But there's really a multiple menu of options for water supply.

"Reservoirs are the last option because they're so expensive and cause environmental problems.''

Historically, reservoirs have been the water supply of choice for areas that rely on surface water in Georgia, North Carolina and Texas, three of the four most populous and fastest-growing states in the South.

They're even used in swampy Florida, which depends mostly on groundwater.

But as increasing demand for water has begun to outstrip available supplies in rapidly developing parts of the four states, water planners have begun looking to alternatives, including newer technologies.

Among the emerging options are:

Inter-basin transfers, a supply-and-demand concept that moves water from less populous areas where it's abundant to growing communities struggling to keep up with rising demand.

Aquifer storage and recovery, a technology roughly equivalent to putting reservoirs underground. As practiced in many areas, treated water is pumped into an aquifer during the rainy season, to be recovered during dry periods.

Desalinization, the capturing and conversion of salt water into a potable water supply. In the United States, most desalinization involves brackish water -- including water from bays and other inlets -- because of the costs of treating saltier water taken directly from an ocean or the Gulf of Mexico.

The reservoir option

Texas is moving away from relying on reservoirs. The latest regional water plans there call for adding only eight new major reservoirs to the existing 211 during the next half century.

Still, reservoirs remain the major strategy for water planners in portions of Georgia and North Carolina that depend on surface water.

Both states' largest population centers -- except for Charlotte, N.C. -- are located in regions without large natural water sources, near the headwaters of river systems.

"We're at the upper end of all of the watersheds,'' said Joel Cowan, chairman of the Atlanta-based Metropolitan North Georgia Water Planning District. "All we can do is catch water at a point and use it.''

The place where Atlanta catches water is 38,000-acre Lake Lanier, a reservoir built by the U.S. Army Corps of Engineers in the 1950s.

The lake has allowed the burgeoning region to withstand periodic droughts, including the persistent dry spell that began in May 1998.

"By having that lake, it's like having something in the bank,'' said Cowan. "We can take it out in wet times and save it for dry times.''

But reservoirs don't come cheap. The new 500-acre Bear Creek Reservoir in Northeast Georgia, for example, cost the four counties cooperating in the venture $36 million.

The Georgia Board of Natural Resources recently approved nearly $50 million in bonds for a 2,300-acre reservoir in western Georgia near the Alabama line.

Reservoirs also have become a target of environmental advocates. According to a recent study conducted by the University of Georgia, damming major rivers or even their tributaries to form reservoirs makes it difficult to maintain downstream channels capable of handling periods of high water flow.

The study said the interruption of natural stream flows also harms fish and other aquatic species, contributing to the depletion of coastal Georgia's commercial fisheries.

"For Georgia to be stuck in that old-school mind-set that we have to be building reservoirs is ridiculous,'' said Alice Miller Keyes, an environmental policy analyst for The Georgia Conservancy and contributor to the study.

Moving water around

Both Georgia and North Carolina are supplementing reservoirs with limited inter-basin transfers. The North Carolina legislature passed a law in 1993 to protect so-called "donor'' river basins.

Applicants for inter-basin permits involving two million gallons per day or more must perform detailed environmental assessments showing how the transfer would affect both the river basin getting the water and the basin giving up the supply. They also must demonstrate that they've looked at alternatives and have adequate water-conservation and drought-management plans.

With all of those hurdles to clear, state regulators have approved only two major inter-basin transfers in North Carolina, in the Charlotte area and in the Research Triangle region near Raleigh.

Tom Fransen, water allocation chief of the North Carolina Division of Water Resources, said the process also is fraught with political controversy.

"A lot of times, the source of water is in a poor, less-populated area going into a wealthier, faster-growing area,'' he said.

The same dynamic is at work in Georgia, where fear that Atlanta-area politicians will use inter-basin transfers to grab water from less-populous communities prompted the legislature last year to ban transfers from outside metro Atlanta into the thirsty region.

New technology

Technology-based water-supply options also have been received warily in Georgia. When a private business sought permission to bring aquifer storage and recovery (ASR) to the Savannah area several years ago, state lawmakers slapped a moratorium on the project.

Coastal environmentalists argue that not enough is known about the effects of injecting treated surface water into the nearly pristine Floridan aquifer.

But ASR has been a water-supply mainstay in parts of Florida for a decade. The city of Cocoa was among the first, drilling ASR wells in the early 1990s to keep up with demand fueled by the nearby Kennedy Space Center. Today, the city stores about 500 million gallons of water underground, enough to meet its average water consumption of 17 million gallons of day for a long, dry spell.

"It's like a savings account,'' said Ed Wegerif, Cocoa's water resources manager, using an analogy similar to Cowan's description of reservoirs. "It makes the system more reliable.''

However, there are limits where Florida will not go. Last year, state lawmakers rejected legislation that would have allowed raw water to go into ASR wells, after an outcry from environmental advocates.

Wegerif said testing is under way to measure the effects of injecting underground the contaminants found in raw water.

Florida also has been a national leader in exploring desalinization. While there are only three small desalinization plants operating in northeast Florida -- the largest, with a capacity of 2.2 million gallons a day, is in Palm Coast -- Tampa Bay Water is building the largest in the nation. At 25 million gallons a day, it's being designed to complement the 15-billion-gallon reservoir the utility is building south of Tampa.

The Southwest Florida Water Management District is kicking in $183 million to support the two projects in exchange for a commitment by Tampa Bay Water to reduce its groundwater pumping, which dries up fragile wetlands.

Costly technique

Desalinization, long in use in arid parts of the world, has been slow to catch on in this country because of the expense. But the costs have come down in recent years with the development of less-expensive membranes used to filter out salt.

Ken Herd, engineering and projects manager for Tampa Bay Water, said the utility is keeping its costs down by taking advantage of the availability of water from the bay that gave the region its name.

"What made our project economical is the salinity in the bay,'' he said. "The salt levels aren't as high as in the Gulf of Mexico.''

But the salinity challenge is not stopping Texas from moving forward with a pilot project to take 25 million gallons of water a day directly from the Gulf.

Bill Mullican, deputy executive administrator for planning for the state's Water Development Board, puts the price tag at $250 million to $300 million, depending on whether project planners can find a site near a power plant. That would allow them to use an existing network of pipelines.

The trade-off, said Mullican, is a dependable source of water in a state that has been plagued by periodic severe droughts.

"Gulf water is drought-proof,'' he said. "It doesn't matter how long a drought lasts. It's going to be there.''

Keefer said Georgia, too, must be willing to consider such trade-offs.

"Most people understand that we're in a water-supply crunch,'' she said. "But I don't think they appreciate what the challenges are.

"They say, 'We don't want reservoirs.' But when you look at the alternatives, people don't want to go there. ... We're going to have to embrace some of these new technologies.''

Staff writer Dave Williams can be reached at (404) 589-8424 or via e-mail at davemns@mindspring.com.