UF Researchers Looking To Alternative Sources For Tomorrow’s Water

October 28, 1996

GAINESVILLE —The old saying, “You don’t miss your water until your well runs dry,” soon could ring true in Florida, experts say, unless someone figures out where the state’s future water supplies will come from.

Researchers at the University of Florida’s Center for Applied Optimization are doing just that. They’re studying the east central Florida area that includes the burgeoning metropolis of Orlando, as well as Volusia County, which includes Daytona Beach.

“Those two areas are projecting big growth,” said Carol Demas, a research associate working on the project. “And they’re expecting public water demands to double.”

Currently, water supply for those areas is derived from wells tapping the Floridan aquifer system, a massive limestone aquifer which exists beneath all of Florida and portions of South Carolina, Georgia and Alabama. Implementing current plans to meet projected demands for the year 2010 could potentially create problems for sensitive wetlands, saltwater intrusion, and reduction in spring discharges.

Because of the concern for adequately planning for future water supplies, the state Legislature ordered the St. Johns River Water Management District and other water management districts to thoroughly evaluate water needs and sources through the year 2010 and beyond. The districts are charged with investigating problems that could arise from the expected growth and developing alternative solutions to avoid problems from occurring.

“There are too many possibilities because there are just thousands of wells and other potential water sources in the area,” Demas explained. “So, we’re developing this tool that will help the St. Johns River Water Management District evaluate water allocation schemes that minimize the cost of meeting demands, while maintaining environmental standards at some critical constrained levels.”

To assist the St. Johns district, the UF researchers are developing decision models to determine optimum water allocation strategies to satisfy future public and agricultural water demands. The models provide valuable insight as to potential water problem areas and will assist water suppliers and managers in developing appropriate future water supply alternatives.

Alternative sources include surface water from rivers, interconnects between municipalities, saline water from deep within the aquifer and reclaimed water which can be used to meet non-potable water demands. “With so many possible water allocation plans to consider, decision modeling provides a useful tool for identifying the most cost-effective water allocation scenarios that minimize environmental impact,” Demas said.

With the ability of the aquifer to transmit water varying greatly from one place to another, the placement of future wells is paramount. “All sites are not equal as far as hydrologic or environmental impacts,” Demas said. “That’s the bottom line.”

Groundwater simulation models developed by the district show how various pumping schemes affect the water pressure and quality in the Floridan aquifer system.

“The decision model will assist water resource managers in developing plans to avoid the many threats to the Floridan aquifer, including saltwater intrusion and loss of water pressure in Florida’s natural springs,” said Kirk Hatfield, UF associate professor of civil engineering.

The model will give the St. Johns River Water Management District a quantitative starting point from which to base its decisions concerning future water supplies. “If you did not have this, people would just come in and start expressing their opinion and political power would probably rule the day,” said Donald Hearn, a UF industrial & systems engineering professor and co-director of the Center for Applied Optimization.

The decision model will be capable of providing several acceptable solutions to a water supply problem, but it will ultimately be left to water suppliers to determine the water supply strategy to be implemented.