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Mosquito Springs Run main view
Mosquito Springs Run
Mosquito Springs Run is a third-magnitude spring with a series of vents in the main pool and run (labeled 1, 2, 3, 4, and 5). The spring head is at the bottom of a steep ravine and has two main vents (1 and 2) in a pool about 20 feet long by 10 feet wide. Vent 1 is in the south part of the pool, and vent 2 is in the north part. Green algae and white sulfur-reducing bacteria are present in the pool. About 140 feet down the run, a tree across the run can be used as a bridge to walk to the other side of the run to sand boil 3, situated in a small run on the right (south) side of the main spring run. Sand boil 4 is in the main spring run about 20 feet toward the northeast of sand boil 3. The ravine becomes less steep downstream as the run flows into a broad wetlands area. Sand boil 5 is in a seepage area to the south-southeast of vent 3 (a camping area is on the upland area to the east of vent 5).
A view of Mosquito Springs Run
Discharge at Mosquito Springs Run was measured in the spring run downstream from all the spring vents. Discharge was measured four times by the U.S. Geological Survey (USGS) from 1997 to 2001 and once by St. Johns River Water Management District in 2005. The difference between the minimum and maximum discharges is 2.71 cubic feet per second (cfs) over the period. The maximum discharge of 2.87 cfs was measured in April 2005; the minimum discharge of 0.16 cfs was measured in June 1997. The mean and median discharges for the period from 1997 to 2005 are 1.59 cfs and 1.8 cfs, respectively (see the table below).
Mosquito Springs Run was sampled once by USGS in 1997 and once by the district in 2005. Sample collection was from the main pool. Summary statistics of the water quality data for selected variables are shown in the table below.
Summary statistics of water quality and discharge at Mosquito Springs Run
|Mosquito Springs Run||Min||Mean||Median||Max||Count||Period|
|Alkalinity, total, mg/L as CaCO3||143.0||143.0||143.0||143.0||1||2005|
|Calcium, total, mg/L as Ca||48.3||48.3||48.3||48.3||1||2005|
|Chloride, total, mg/L as Cl||7.5||7.9||7.9||8.2||2||1997−2005|
|Magnesium, total, mg/L as Mg||4.5||4.5||4.5||4.5||1||2005|
|Nitrate + nitrite, total, mg/L as N||0.01||0.01||0.01||0.01||1||2005|
|Orthophosphate, total, mg/L as P||0.20||0.20||0.20||0.20||1||2005|
|Phosphorus, total, mg/L as P||0.22||0.22||0.22||0.22||1||2005|
|Sodium, total, mg/L as Na||4.7||4.7||4.7||4.7||1||2005|
|Specific conductance, field, µmhos/cm at 25°C||297||297||297||297||1||2005|
|Specific conductance, lab, µmhos/cm at 25°C||274||275||275||276||2||1997−2005|
|Sulfate, total, mg/L as SO4||0.5||0.5||0.5||0.5||1||1997|
|Total dissolved solids, mg/L||150||151||151||152||2||1997−2005|
|Water temperature, °C||21.8||21.9||21.9||22.0||2||1997−2005|
mg/L = milligrams per liter
cfs = cubic feet per second
Age of discharge water
The age of water discharging from Mosquito Springs was determined by measuring the concentration of tritium, carbon-14, and carbon-13 in the spring discharge, which was measured in April 2005. Mosquito Springs had a tritium concentration of 1.88 tritium units, a carbon-14 concentration of 50% modern carbon, and a delta carbon-13 value of −9.72 parts per thousand. The tritium concentrations suggest that the water is less than 50 years old. The carbon-14 concentration can result from the reaction of rainfall with calcite, dolomite, and soil organic matter.