Holy Perrier! Survey Reveals 200 New Springs
03By NEIL JOHNSON
TAMPA — A three-year survey of the state’s springs uncovered nearly 200 more than were known to exist and also tracked what may be a decline in their volume and water quality.
Conducted by the state Department of Environmental Protection, the survey was part census, part scientific study released in mid-October. T
eams of scientists spent two to three weeks a month during the survey locating, documenting and testing springs, and visiting 463 of the 740 known springs in the state.
“It was to get an idea of what condition the springs are currently,” said Mike Bascom, director of the DEP’s Springs Initiative. The last survey was done in 1977.
The newly documented springs ranged from one that produces more than 6.4 million gallons a day to tiny seeps that put out less than a pint of water a minute.
Most were in the Panhandle around the Suwannee River area, which has the largest concentration of Florida’s springs.
The survey also found some of the state’s largest, best-known springs may be producing less water than the average flow of the past.
Weeki Wachee, Silver and Wakulla Springs all showed a reduction in volume when measured in 2001, the year the survey started. The average flow from Weeki Wachee between 1917 and 1974 was 176 cubic feet of water a second. In 2001, it was 161 cubic feet.
The others showed a similar drop: Silver Springs was 556 cubic feet per second in 2001 compared with the average of 820 cubic feet per second. Wakulla Springs was 129 cubic feet a second in 2001, but the average is 390 cubic feet a second.
A cubic foot of water is about 7.5 gallons.
There could be several reasons for the decline in spring flow, Bascom said.
The measurements taken in 2001 were near the end of a three-year drought that started in 1998. Spring flows are highly dependent on rainfall. However, there is little doubt increasing use of groundwater to supply a growing population is having some effect.
“We can say consumption is part of it, but we can’t say how much. We know it’s a contributing factor and in Florida it’s a big one,” Bascom said.
Scientists are looking at the spring flows to determine how much of the change is related to weather and how much is linked to tapping the aquifer for drinking water.
The survey also looked at levels of nutrients in spring water such as nitrates that can act as fertilizer and spur plant and algae growth.
The amount of nutrients is generally increasing across the state, the survey showed. But scientists are examining the samples to study just how much they are increasing.
The nutrients can come from residential and golf course fertilizer that seep into groundwater, septic tanks and agriculture.
Because the water flowing from springs has been underground an average of 25 years, the nutrient levels may be more a snapshot of the past.
“What we see today may be an indication of what conditions were in 1980,” Bascom said.
Copyright (c) 2004 The Tribune Co.