In this section
Sweetwater Springs main view
Sweetwater Springs (and Little Sweetwater Spring)
Sweetwater Springs is a second-magnitude spring with a picturesque spring pool about 70 feet long by 60 feet wide. Clear, light blue water flows from two oval-shaped vents about 4 to 5 feet long, with exposed limestone around the vents. Boils are visible over the vents. The discharge flows southward about 80 feet to Juniper Creek.
Discharge at Sweetwater Springs was measured by the U.S. Geological Survey (USGS) 40 times from 1980 to 2002. St. Johns River Water Management District measured discharge 182 times from 1985 to 2010 and currently measures discharge six times per year. The difference between the minimum and maximum discharges is 15.88 cubic feet per second (cfs) over the period. The maximum measured discharge of 23.0 cfs occurred in June 1987; the minimum discharge of 7.12 cfs occurred in November 1987. The mean and median discharges for the period from 1980 to 2010 are 13.06 cfs and 13.00 cfs, respectively (see the table below).
Sweetwater Springs was sampled by USGS in 1980, with additional field measurement at other times through 1999. The district sampled Sweetwater Springs 77 times, from 1985 to 2010, and currently samples the spring four times per year. Summary statistics of the water quality data for selected variables for Sweetwater Spring are shown in the table below.
The field-specific conductance of Little Sweetwater Spring is 5,590 µmhos/cm, at 25°C. The pH is 7.5. No other water quality or discharge data are available for Little Sweetwater Spring.
Summary statistics of water quality and discharge at Sweetwater Springs
|Alkalinity, total, mg/L as CaCO3||64.0||71.6||71.3||80.1||75||1985−2010|
|Calcium, total, mg/L as Ca||87.7||100.6||100.8||116.0||71||1992−2010|
|Chloride, total, mg/L as Cl||824.0||1019.4||1019.0||1420.0||76||1980−2010|
|Fluoride, total, mg/L as F||0.09||0.12||0.12||0.14||39||1994−2003|
|Magnesium, total, mg/L as Mg||51.2||58.1||58.0||67.1||69||1992−2010|
|Nitrate + nitrite, total, mg/L as N||0.01||0.05||0.04||0.27||75||1989−2010|
|Orthophosphate, total, mg/L as P||0.01||0.03||0.02||0.24||62||1994−2010|
|Phosphorus, total, mg/L as P||0.01||0.02||0.02||0.04||26||1996−2010|
|Potassium, total, mg/L as K||12.9||17.5||17.4||22.9||70||1992−2010|
|Sodium, total, mg/L as Na||450.0||537.2||540.0||622.0||69||1992−2010|
|Specific conductance, field, µmhos/cm at 25°C||2142||3488||3670||4322||68||1985−2010|
|Specific conductance, lab, µmhos/cm at 25°C||2610||3729||3720||4350||57||1980−2010|
|Sulfate, total, mg/L as SO4||197.0||250.4||251.8||296.0||78||1980−2010|
|Total dissolved solids, mg/L||1620||2081||2065||2510||76||1980−2010|
|Water temperature, °C||20.7||23.1||23.2||24.5||93||1980−2010|
mg/L = milligrams per liter
cfs = cubic feet per second
Age of discharge water
Sweetwater Springs Run
The age of water discharging from Sweetwater Springs was determined by measuring the concentration of tritium, delta carbon-13, and carbon-14 in the spring discharge, which was measured in May 1996. Sweetwater Springs had a tritium concentration of 1.2 tritium units, which suggests that the water is less than 70 years old. Sweetwater Springs had a delta carbon-13 value of −8.10 parts per thousand and a carbon-14 concentration of 16% modern carbon, which results from the mixing of Upper and Lower Floridan aquifer water. The adjusted carbon-14 age is recent.