Connector well experiment to recharge the Floridan aquifer, east Orange County, Florida

An experimental connector well, screened in the shallow sand aquifer, finished with open hole in the Floridan aquifer and cased through the confining layer between the two aquifers, was drilled in east Orange County, Fla., to obtain information on the nature and function of the shallow aquifer as related to connector well operation. The potentiometric surface of the shallow aquifer is about 45 feet higher than the potentiomettic surface of the Floridan aquifer; hence water flows by gravity from the shallow aquifer to the Floridan aquifer through the well 'connecting' the two aquifers. Continuous flow measurement over 10 months shows the well discharge varies seasonally and averages slightly more than 50 gallons per minute. Observation wells show that, except for seasonal variation, water levels within the area of influence have reached steady state within measurable limits. Vertical anisotropy in the shallow aquifer is apparently caused by the shape and (or) arrangement of the sand grains that comprise the shallow aquifer, rather than because of distinct confining layers of different lithology. Transmissivity of the shallow aquifer at the site is about 600 square feet per clay. Extensive dewatering of wetlands in east Orange County by connector wells alone probably is not feasible. Nevertheless, large amounts of water could be channeled to the Floridan aquifer by connector wells. The results of the connector well experiment imply that water is being captured from evapotranspiration and interception of water that would have discharged to swamps in the vicinity of the connector well. However, the data available from this experiment do not permit a quantitative expression of the net gain in recharge to the Floridan aquifer resulting from operation of the connector well.