Water bodies, watersheds and storm water

Droty Spring main view

Droty Spring pool

Droty Spring run
Droty Spring
Location
Droty Spring is located in the Seminole State Forest about 3 miles northeast of Mount Plymouth and 1.7 miles south of the town of Seminole Springs. From the intersection of State Road (SR) 46 and County Road (CR) 46A, turn north onto CR 46A and drive 3.2 miles to a gate. If driving from the north, turn south onto CR 46A from SR 44 and drive 2.4 miles. Park, then cross the gate onto Seminole State Forest property. Walk about 150 feet toward the northeast to the spring at the bottom of a ravine. Access and fee information can be obtained at the Seminole State Forest south entrance.
Latitude 28°49’41.04” N, Longitude 81°30’37.30” W
NW¼ NW¼ NW¼ sec. 22, T 19 S, R 28 E
Description
Droty Spring is a fourth-magnitude spring that discharges from sand boils in a small, circular pool at the bottom of a ravine. The sandy spring run is about 4 feet wide and flows about 500 feet toward the northeast into Seminole Creek. Oak, pine, palm, and banana trees are common in the area around the spring and run.
Discharge

White bacteria growing in Droty Spring
Discharge at Droty Spring was measured by the U.S. Geological Survey in 1997 and by St. Johns River Water Management District (SJRWMD) in 2005 and 2008. The mean discharge is 0.65 cubic feet per second (see the table below).
Water quality
Droty Spring was sampled twice in 2004 by Lake County and once by SJRWMD in 2005. Summary statistics of the water quality data for selected variables are shown in the table below.
Summary statistics of water quality and discharge at Droty Spring
| Droty Spring | Min | Mean | Median | Max | Count | Period |
|---|---|---|---|---|---|---|
| Discharge, cfs | 0.59 | 0.65 | 0.65 | 0.72 | 3 | 1997–2008 |
| Alkalinity, total, mg/L as CaCO3 | 109.0 | 110.6 | 110.7 | 112.0 | 3 | 2004–2005 |
| Calcium, total, mg/L as Ca | 34.2 | 37.3 | 37.1 | 40.6 | 3 | 2004–2005 |
| Chloride, total, mg/L as Cl | 7.1 | 7.2 | 7.1 | 7.3 | 3 | 2004–2005 |
| Dissolved Oxygen | 0.56 | 0.68 | 0.68 | 0.80 | 2 | 2004 |
| Magnesium, total, mg/L as Mg | 9.5 | 10.2 | 10.0 | 11.1 | 3 | 2004–2005 |
| Nitrate + nitrite, total, mg/L as N | 0.03 | 0.03 | 0.03 | 0.03 | 1 | 2004 |
| Orthophosphate, total, mg/L as P | 0.08 | 0.08 | 0.08 | 0.08 | 1 | 2005 |
| pH, field | 7.60 | 7.79 | 7.79 | 7.97 | 3 | 2004–2005 |
| Phosphorus, total, mg/L as P | 0.08 | 0.08 | 0.08 | 0.08 | 1 | 2005 |
| Potassium, total, mg/L as K | 0.6 | 0.7 | 0.7 | 0.8 | 2 | 2004 |
| Sodium, total, mg/L as Na | 4.1 | 4.3 | 4.3 | 4.5 | 2 | 2004–2005 |
| Specific conductance, field, µmhos/cm at 25°C | 298 | 303 | 305 | 305 | 3 | 2004–2005 |
| Specific conductance, lab, µmhos/cm at 25°C | 291 | 291 | 291 | 291 | 1 | 2005 |
| Sulfate, total, mg/L as SO4 | 28.9 | 30.2 | 30.2 | 31.4 | 2 | 2004–2005 |
| Total dissolved solids, mg/L | 167 | 175 | 176 | 183 | 3 | 2004–2005 |
| Water temperature, °C | 23.8 | 24.0 | 24.0 | 24.2 | 3 | 2004–2005 |
mg/L = milligrams per liter
cfs = cubic feet per second
Age of discharge water
The age of water discharging from Droty Spring was determined by measuring the concentration of tritium, carbon-14, and carbon-13 in the spring discharge, which was measured in March 2005. Droty Spring had a tritium concentration of 0.95 tritium units and a carbon-14 concentration of 31 percent modern carbon and a delta carbon-13 value of –8.86 parts per thousand. The tritium concentration suggests that the water is less than 50 years old. The carbon-14 concentration of 31% modern carbon can result from the reaction of rainfall with calcite, dolomite, and soil organic matter.


