All not sold on aquifer recharge

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By Mark Scohier, Staff writer

State water managers are moving forward with a project they say could help replenish dwindling portions of the Upper Floridan Aquifer, though others are questioning the logic behind the move.

The Suwannee River Water Management District, partnering with the St. Johns River Water Management District and the Florida Department of Environmental Protection, hired Atkins North America Inc. in July to undertake a study to determine the potential success of recharging the aquifer with reclaimed water and surface water.

The study, still in its early phases, is a portion of a joint effort between the three agencies known as the North Florida Aquifer Replenishment Initiative, which, according to the study thus far, would “benefit lakes, springs, rivers and wetlands, and contribute to developing a sustainable water supply for the region.”

Groundwater levels throughout the SRWMD area saw record lows earlier in the year, due to drought and groundwater withdrawal. Springs quit flowing. Residential wells dried up. Coastal communities, such as Cedar Key, saw their municipal wells flooded with saltwater as the bubble of fresh groundwater that keeps it at bay became smaller and smaller. Levels came back up with the onset of two tropical storms, though, as some predicted, levels are beginning to fall again, dropping by an average of 1 foot for the Upper Floridan Aquifer, according to a recent report from SRWMD.

And that’s why agencies would like to recharge the aquifer and use it as a large storage tank. Four conceptual approaches were outlined in the latest Atkins report on the matter, though each will need to be studied further for their likelihood of success.

The first involves using wastewater from the SJRWMD area using direct and indirect methods of recharge for portions of the aquifer in that district. Direct recharge involves injecting the water deep into wells. Indirect uses ponds, wetlands, sinkholes, mine pits and other such features to recharge the upper levels of the aquifer. The second plan involves capturing and storing water from the Upper Suwannee River for treatment and direct recharge into the aquifer. The third considers capturing flood water from floodplains on the Upper Suwannee for storage and indirect recharge, and the last calls for capture and storage of surface water in the SJRWMD area into the aquifer.

But some of these techniques have proven controversial.

Merrillee Malwitz-Jipson, president of Our Santa Fe River, has followed issues associated with aquifer recharge for years.

“I have been telling them that I have a concern about the chemicals that they cannot remove,” Malwitz-Jipson said last week in a phone interview with regard to treated wastewater sent into the aquifer.

The U.S. Environmental Protection Agency and FDEP have standards about the removal of solids and biodegradable organic compounds, but most treatment processes are not designed to remove things such as pharmaceuticals, detergents or chemicals from plastics, all of which, according to Malwitz-Jipson, act as endocrine disruptors. 

The endocrine system in animals, including humans, acts as the body’s means for communication in regulating glands, hormones and cellular receptors. A 2007 study by the U.S. Geological Survey determined that wastewater caused endocrine disruption in certain fish, causing the males to begin producing a female egg-yolk protein. Wastewater also often contains known carcinogens and drug-resistant bacteria and viruses.

But in areas where wastewater is not being considered, such as on the Upper Suwannee River, Malwitz-Jipson said there are also concerns with dissolved oxygen put into the aquifer from direct recharge methods that have been shown to release naturally occurring radioactive material in the rock and poisonous metals such as arsenic.

An early study by USGS showed that an “appreciable amount” of uranium (25 part per million) occurs in the limestone in the Floridan Aquifer and that “more than 30 percent of the uranium can be leached from the rock under oxidizing conditions in the laboratory.” The report went on to state that the data was “especially significant” to aquifer storage and recovery (ASR) in Florida because ASR areas contain more dissolved oxygen than what would naturally occur within the aquifer. Arsenic is also released, the study showed, though levels of both arsenic and uranium appear to decline as dissolved oxygen-rich water is injected and then removed over several cycles.

Still, this is no comfort to some. 

 ” It makes sense that once the exposed pyritic deposits have reacted with the oxygen and mixing occurs that levels would drop. The trick is that it is unpredictable. In our part of the world it might poison a season of a crop or a herd of cattle before any realized there was a problem,” said Annette Long, of Save Our Suwannee.

An alternative to ASR is shallow injection through the use of wetlands, she said. “We wrecked them all by draining them, but if we take treated effluent and allow it to recharge from the surface, like it’s supposed to, it solves a lot of problems.”

Cutting down on the number of millions-of-gallons-per-day consumptive use permits would be a cheaper option, she said, instead, the water management districts are spending hundreds of thousands of dollars on studies to determine if artificial groundwater recharge using wastewater, floodwater, deep aquifer water from mine wells and “plain old river water” will solve the problem.

“They are doing this because pumping ground water is the way we have always done it in Florida,” she said. “What they aren't doing is mandatory conservation.  Another thing that doesn't seem to be on the table is complete re-use of wastewater. Clean it up to drinking water standards and use it again, instead of pumping new groundwater.”

Capturing floodwaters from floodplains on the Suwannee River isn’t an answer, either, she said. Floodwaters are important, too. The water flowing down the Suwannee River, even during floods, is not “extra water,” she said. It’s important for fisheries, clams, oyster beds and sea life where the river meets the Gulf. 

“Who decides that the existing sport and commercial fishing, shellfish and tourism industry is less important than issuing new water permits for housing developments, new industrial developments and new farmland?

“It's got to stop. All you have to do is look at the lakes, look at the springs and rivers to see there is a terrible problem. The science is clear and settled — record low flows and rising salinity. For the water management district to be spending millions of taxpayer dollars to fix our water crisis with band aid projects while continuing to hand out new water use permits is illegal and wrong. We need our leaders to follow the rules and to open their eyes and see the facts.”