Caribbean-Florida Water Science Center
Saltwater intrusion monitoring in Florida
Project Chief: Scott T. Prinos
Background and Problem Statement
In Florida, saltwater has intruded through a number of pathways including: (1) encroachment of seawater into aquifers in response to decreased fresh groundwater levels relative to sea level, (2) the flow of saltwater inland through canals, rivers, boat basins, and coastal marshes and subsequent leakage of this saltwater into aquifers, (3) movement of connate or relict saltwater in an aquifer, and (4) leakage of saltwater between aquifers (Prinos 2013). The reductions in fresh groundwater levels could be caused by public and private water supply withdrawals from aquifers, excessive drainage, reductions in precipitation, or increases in sea level. Saltwater in some aquifers might have emanated from multiple pathways. For example, saltwater leaking from canals might merge with saltwater from the sea that is encroaching inland along the base of the aquifer.
As water managers work to prevent and reverse saltwater intrusion in Florida, they use information from local, State, and Federal saltwater intrusion monitoring networks; however, there is considerable variability in the quality of monitoring conducted in the counties of Florida.
To provide a basic understanding of state-of-the-art saltwater intrusion monitoring that has been implemented in some areas in Florida, and to describe how saltwater intrusion monitoring in the rest of Florida could be improved.
Case studies are provided so that the differences between state-of-the-art saltwater intrusion monitoring and older salinity monitoring strategies can be described. The benefits and deficiencies of monitoring strategies are discussed.
An article published in the Florida Scientist: Saltwater intrusion monitoring in Florida.
Prinos, S.T., 2013, Saltwater intrusion in the surficial aquifer system of the Big Cypress Basin, southwest Florida, and a proposed plan for improved salinity monitoring: U.S. Geological Survey Open-File Report 2013-1088, 58 p.
Schmerge, D.L., 2001, Distribution and origin of salinity in the surficial and Intermediate Aquifer Systems, southwestern Florida: Water-Resources Investigations Report 01-4159, 41 p.
Generalized flow patterns, southwestern Florida. Brackish water in the well from the Upper Floridan aquifer is moving into freshwater zones of the mid-Hawthorn, sandstone, and lower Tamiami aquifers. Figure modified from Schmerge (2001).