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Clay-Putnam MFL prevention/recovery strategy development process
History of the Keystone Heights area lakes
The Keystone Heights area lakes are located on a high sand ridge in southwestern Clay County. The lakes were created when a layer of limestone collapsed. This limestone now lies beneath the lakes’ sandy bottoms, along with a layer of clay. This karst terrain is a natural geologic feature and is a contributing factor to the fluctuation in lake levels that have occurred over many decades.
Keystone Heights area lakes receive water from:
- Directly capturing rainfall
- Stormwater runoff
- Groundwater infiltration from the surficial aquifer system (or seepage from the aquifer)
- Streams fed by groundwater infiltration
- Flow from other lakes
These three pools of water combine to make one large lake (Lake Brooklyn) during times of higher water levels. This photo was taken in July 2002 at the height of a drought.
This photo of Lake Brooklyn from 2005 shows how the lake had risen due to increased rainfall in the area.
Water levels in Lake Brooklyn were above average in April 1996.
This photo from 2009 shows a healthy inflow of water to Lake Brooklyn from Alligator Creek.
Rainfall is the only source of water for all of these flow paths to lakes.
Blue Pond and lakes Lowry, Magnolia, Brooklyn and Geneva are interconnected by streams, known as Alligator Creek. The lakes in the Alligator Creek chain all leak downward into the Floridan aquifer system. When Alligator Creek ceases to flow into Lake Brooklyn, the lake’s level rapidly falls. When Alligator Creek starts flowing, water levels in the lakes at the end of the chain begin to rise. Lake Brooklyn exhibits large fluctuations in water levels as water drains to the aquifer during dry periods and as water is replenished faster than it drains during wet periods.
The St. Johns River Water Management District has been involved in many projects over the years to better understand the lakes. District work has included:
- Analyzing area rainfall patterns (hydrology) and the movement of water through the system (hydrodynamics)
- Providing funds for an independent consultant to investigate the causes of low lake levels (Schreuder Report, 2002)
- Cooperatively funding water resource investigations by the U.S. Geological Survey
- Cost-sharing with Suwannee River Water Management District and DuPont on a project to recapture part of DuPont’s Florida mine surface discharge and redirect it to the Keystone lakes watershed
- Permitting local projects to improve flow to the Alligator Creek system
- Monitoring surface and groundwater levels
- Requiring local mining operations to reduce their dependence on groundwater
Posted on 1-18-2013