St. Johns River Water Management District St. Johns River Water Management District St. Johns River Water Management District St. Johns River Water Management District St. Johns River Water Management District St. Johns River Water Management District
St. Johns River Water Management District - floridaswater.com

Contact us

In this section
Highlights
More about
Contact us

Next Governing Board meeting April 13, 1 p.m.

Next permitting public meeting March 29, 1:30 p.m.

By accessing this site, you agree to accept terms and conditions of the District’s liability disclaimer.

Go to MyFlorida.com
Water bodies, watersheds and storm water
Silver Glen Springs Aerial View

Silver Glen Springs Aerial View

Silver Glen Springs






Location

Silver Glen Springs Pool

Silver Glen Springs Pool

Silver Glen Springs is located in the Silver Glen Springs Recreational Area of the Ocala National Forest, about 11 miles south of the town of Salt Springs. From the intersection of State Roads (SR) 19 and 40, drive north on SR 19 for 6 miles to the entrance of the recreational area on the east (right) side of the road; the spring is situated south of the parking area.

Latitude 29°14'45.04" N, Longitude 81°38'36.50" W
SE¼ NE¼ SE¼ sec. 25, T 14 S, R 26 E

Mapquest location map of Silver Glen Springs

Description

Silver Glen Springs Main Vent

Silver Glen Springs Main Vent

Silver Glen Springs is a 1st magnitude spring with a large, semicircular pool that measures 200 feet north to south and 175 feet east to west. Most of the strong flow emerges from two cavern openings in the rock at the bottom of the pool, with large boils at the water's surface over the vents. The vertical cave opening called the Natural Well in the southwestern edge of the pool is about 12 to 15 feet in diameter and 40 feet deep. The vent in the east part of the pool is a conical depression about 18 feet deep. Most of the spring pool has sand and limestone on the pool bottom, with areas of aquatic grasses. Large fresh and salt water fish are common in the pool and around the vents. Additional flow is from sand boils in the bottom of the spring run downstream from the head of the springs. Water from the springs flows eastward down a run about 200 feet wide for 0.75 mile to Lake George.

The spring is part of the USDA Forest Service's Silver Glen Springs Recreation Area. The recreation area is used for swimming, snorkeling, picnicking, fishing, and boating. Boating is not allowed in the spring pool, but the spring run is a popular spot for recreational boaters.

Discharge

Silver Glen Springs Run Outlet into Lake George

Silver Glen Springs Run Outlet into Lake George

Discharge at Silver Glen Springs was measured by the U.S. Geological Survey 57 times from 1931 to 2003. St. Johns River Water Management District (SJRWMD) measured discharge 118 times from 1983 to 2005, and currently measures discharge 12 times per year. The difference between the minimum and maximum discharges is 207 cubic feet per second (cfs) over the period. The maximum measured discharge of 245 cfs occurred in April 1983; the minimum discharge of 38.2 cfs occurred in October 2004. The mean and median discharges for the period from 1931 to 2005 are 104 cfs and 100 cfs, respectively (Table 1).

Silver Glen Springs Discharge Graph
Discharge Graph

Water quality

Silver Glen Springs Underwater View of Pool

Silver Glen Springs Underwater View of Pool

Silver Glen Springs was sampled by the U.S. Geological Survey 8 times from 1972 to 1997, with additional field measurement at other times through 1999. SJRWMD sampled Silver Glen Springs 56 times from 1984 to 2005, and currently samples the spring four times per year. Summary statistics of the water quality data for selected variables are shown in Table 1.

Silver Glen Springs Water Quality Graph
Water Quality Graph

Table 1. Summary statistics of water quality and discharge at Silver Glen Springs

Silver Glen Springs Min Mean Median Max Count Period
Water temperature, °C 20.5 23.2 23.1 26.0 78 1972-2005
Specific conductance, field, µmhos/cm at 25 °C 956 1882 1938 2184 45 1984-2005
Specific conductance, lab, µmhos/cm at 25 °C 1640 1990 1990 2400 47 1972-2005
pH, field 6.20 7.76 7.80 8.57 69 1972-2005
Discharge, cfs 38.2 104 100 245 175 1931-2005
Calcium, dissolved, mg/L as Ca 55.0 71.1 72.0 83.0 20 1972-2001
Calcium, total, mg/L as Ca 64.0 71.6 71.5 77.6 47 1992-2005
Magnesium, dissolved, mg/L as Mg 23.0 35.9 36.0 52.0 20 1972-2001
Magnesium, total, mg/L as Mg 30.3 35.0 35.0 38.0 47 1992-2005
Sodium, dissolved, mg/L as Na 230.0 271.5 269.0 412.0 20 1972-2001
Sodium, total, mg/L as Na 220.7 251.7 251.7 287.0 46 1992-2005
Potassium, dissolved, mg/L as K 8.2 10.1 9.3 21.6 19 1972-2001
Potassium, total, mg/L as K 7.1 8.8 8.7 12.3 47 1992-2005
Chloride, total, mg/L as Cl 394.0 463.5 456.6 707.0 58 1972-2005
Sulfate, total, mg/L as SO4 154.0 179.6 179.4 214.0 57 1972-2005
Fluoride, dissolved, mg/L as F 0.00 0.16 0.12 0.50 13 1972-1997
Fluoride, total, mg/L as F 0.10 0.12 0.12 0.14 38 1994-2003
Nitrate + nitrite, total, mg/L as N 0.02 0.05 0.04 0.37 51 1984-2005
Nitrate + nitrite, dissolved, mg/L as N 0.03 0.04 0.04 0.05 2 1996-2001
Phosphorus, total, mg/L as P 0.02 0.02 0.02 0.03 11 1972-2005
Orthophosphate, total, mg/L as P 0.01 0.02 0.02 0.04 45 1972-2005
Alkalinity, total, mg/L as CaCO3 62.0 67.6 67.4 80.0 56 1972-2005
Total dissolved solids, mg/L 993 1094 1085 1250 52 1981-2005
Total organic carbon, mg/L as C 0.0 0.4 0.5 0.6 3 1972-1991
Units: µmhos/cm = micromhos per centimeter
         mg/L = milligrams per liter
         cfs = cubic feet per second

Age of discharge water

Large Cave at Silver Glen Springs

Large Cave at Silver Glen Springs

The age of water discharging from Silver Glen Springs was determined by measuring the concentration of tritium, delta carbon-13, and carbon-14 in the spring discharge in April 1996 and the concentration of tritium and helium-3 in the discharge in March 2001. Silver Glen Springs had a tritium concentration of 2.4 tritium units, which suggests that the water is less than 43 years old. The tritium/helium-3 age was 26 years. Silver Glen Springs had a delta carbon-13 value of –7.70 parts per thousand and a carbon-14 concentration of 20% modern carbon, which results from the mixing of Upper and Lower Floridan aquifer water. The adjusted carbon-14 age is recent.

Go to Top