By Erika Webb
Approval of a modified Consumptive Use Permit is expected to reduce Niagara Bottling's impact on Lake County's water resources, according to the St. Johns River Water Management District.
The SJRWMD governing board's Feb. 11 nod grants permission for Niagara to increase its daily water withdrawal from the Floridan Aquifer to nearly a million gallons per day over the next 10 years.
The shift from Upper to Lower Floridan extraction must promise a reduced hydrologic impact compared to its current Upper Floridan use, prior to implementation, the district reported in a news release.
"The governing board considered a great many factors, including the input provided by the public," said Chairman John Miklos of Orlando, according to the release. "Ultimately, we determined that this withdrawal will have a negligible impact on the environment, and there are conditions in place to ensure that there is no unacceptable harm to water resources."
Shifting withdrawals to the Lower Floridan aquifer is consistent with one of the strategies being developed in the Central Florida Water Initiative -- a collaborative regional water supply endeavor to protect, conserve and restore water resources in southern Lake, Orange, Osceola, Seminole and Polk counties, according to the release.
"CFWI goals include crafting long-term water supply solutions for the central Florida region. Niagara's permit includes language for the district to modify withdrawal quantities as appropriate to address impacts and other conditions," the release stated.
Under the terms of the 20-year CUP, Niagara agreed to begin reducing withdrawal from the Upper Floridan by 2016 while gradually increasing removal from the Lower Floridan until 2024, "when all withdrawals will be made from this source."
A semi-confining unit separates the Lower Floridan aquifer from the Upper Floridan aquifer as well as from the land surface. It is made up of softer less permeable limestone and dolomite, compared to that of the Upper and Lower levels.
Niagara's well will be on the northwest side of its property in Groveland, according to SJRWMD Public Information Coordinator Hank Largin.
So, what happens to the middle and top portions of the aquifer when water pumping is shifted to the Lower Floridan?
"Because of this semi-confining unit and the productive nature of the Lower Floridan, district staff concluded that this withdrawal will have less potential to impact the surrounding natural systems than the previously permitted withdrawal," the release stated.
"A permit condition was also included that allows the permit to be revoked or the withdrawal reduced if aquifer tests demonstrate that water use from the Lower Floridan does not provide the benefit anticipated," Mr. Largin noted in an emailed response to questions.
Dr. Kirsten Work, chair of the biology department at Stetson University, agreed Niagara "could be right that switching from upper to lower would have less impact on lakes quite close to the withdrawal site."
That layer of clay, called the intermediate confining unit, restricts water from either entering or leaving the lower aquifer in places where this clay layer is present and intact, Dr. Work explained in an email.
However, she noted, "Areas where the intermediate confining unit is thin are often discharge areas where water seeps out of the lower aquifer into lakes or rivers."
Springs tend to emerge in areas where it is relatively thick but cracked; water shoots out of the crack, forming a spring, she explained.
Dr. Work posed two questions:
How thick is the intermediate confining unit in the vicinity of the Niagara withdrawal site?
Are the lakes near the withdrawal site fed by the lower or upper aquifer?
"Even if switching to the Lower Floridan helps to protect the lakes, it contributes to the over-withdrawal of the lower Floridan aquifer," Dr. Work wrote. "When withdrawals are too high from the Lower Floridan, the pressure in the aquifer declines so that drinking water availability declines, springflows decline and sinkholes become more prevalent."
Two of the eight board members, Douglas Burnett of St. Augustine and Maryam Ghyabi of Ormond Beach, voted against the increase.
The 20 year timeframe was a major sticking point for each.