In this section
Pegasus Spring main view
Pegasus Spring vent
Pegasus Spring boil in run
Pegasus Spring is a third-magnitude spring. The spring head is a small pool with the vent discharging at an angle. The vent opening is approximately 1 to 2 feet wide, discharging about 2 feet below the water’s surface. A sand boil is also present approximately 200 feet down the spring run. Semitropical forests surround the spring, with Starbuck Spring less than 0.1 mile toward the northwest. Ginger Ale Springs and Palm Springs are located 0.3 and 0.4 mile, respectively, toward the south-southwest from Pegasus Spring.
Discharge from Pegasus Spring, measured in 2005 by the St. Johns River Water Management District, was 2.8 cubic feet per second.
Pegasus Spring was sampled by the district in 2005. The water quality data for selected variables are shown in the table below. Water temperature and pH were also measured in 2004.
Summary statistics of water quality and discharge
at Pegasus Spring
|Alkalinity, total, mg/L as CaCO3||108.0||2005|
|Calcium, total, mg/L as Ca||41.7||2005|
|Chloride, total, mg/L as Cl||19.8||2005|
|Magnesium, total, mg/L as Mg||10.5||2005|
|Nitrate + nitrite, total, mg/L as N||0.54||2005|
|Orthophosphate, total, mg/L as P||0.16||2005|
|Phosphorus, total, mg/L as P||0.22||2005|
|Potassium, total, mg/L as K||1.8||2005|
|Sodium, total, mg/L as Na||11.6||2005|
|Specific conductance, field, µmhos/cm at 25°C||370||2005|
|Specific conductance, lab, µmhos/cm at 25°C||361||2005|
|Sulfate, total, mg/L as SO4||43.5||2005|
|Total dissolved solids, mg/L||210||2005|
|Water temperature, °C||23.6||2004−2005|
mg/L = milligrams per liter
cfs = cubic feet per second
Age of discharge water
The age of water discharging from Pegasus Spring was determined by measuring the concentration of tritium, delta carbon-13, and carbon-14 in the spring discharge, which was measured in March 2005. Pegasus Spring had a tritium concentration of 1.09 tritium units, which suggests that the water is less than 52 years old. Pegasus Spring had a delta carbon-13 value of −11.86 parts per thousand and a carbon-14 concentration of 53% modern carbon, which results from the reaction of rainfall with calcite, dolomite, and sediment organic matter. The adjusted carbon-14 age of Pegasus Spring is recent.