Jackson Blue Springs discharging from the Floridan Aquifer. Jackson County, FL. Image: Doug Mayo, UF/IFAS Extension.

Florida has one of the largest concentrations of freshwater springs in the world. More than 1000 have been identified statewide, and here in the Florida Panhandle, more than 250 have been found.  Not only are they an important source of potable water, springs have enormous recreational and cultural value in our state. There is nothing like taking a cool swim in the crystal-clear waters of these unique, beautiful systems.

How do springs form?

We have so many springs in Florida because of the state’s geology.  Florida is underlain by thick layers of limestone (calcium carbonate) and dolomite (calcium magnesium carbonate) that are easily dissolved by rainwater that percolates into the ground. Rainwater is naturally slightly acidic (with a pH of about 5 to 5.6), and as it moves through the limestone and dolomite, it dissolves the rock and forms fissures, conduits, and caves that can store water. In areas where the limestone is close to the surface, sinkholes and springs are common. Springs form when groundwater that is under pressure flows out through natural openings in the ground. Most of our springs are found in North and North-Central Florida, where the limestone and dolomite are found closest to the surface.

Springs are windows to the Floridan Aquifer, which supplies most of Florida’s drinking water. Image: Ichetucknee Blue Hole, A. Albertin.

These thick layers of limestone and dolomite that are below us, with pores, fissures, conduits, and caves that store water, make up the Floridan Aquifer. The Floridan Aquifer includes all of Florida and parts of Georgia, South Carolina, and Alabama. The thickness of the aquifer varies widely, ranging from 250 ft. thick in parts of Georgia, to about 3,000 ft. thick in South Florida. The Floridan is one of the most productive aquifer systems in the world.  It provides drinking water to about 11 million Floridians and is recharged by rainfall.

How are springs classified?

Springs are commonly classified by their discharge or flow rate, which is measured in cubic feet or cubic meters per second. First magnitude springs have a flow rate of 100 cubic feet or more per second, 2nd magnitude springs have a rate of 10-100 ft.3/sec., 3rd magnitude flows are 1-10 ft.3/sec. and so on. We have 33 first magnitude springs in the state, and the majority of these are found in state parks. These springs pump out massive amounts of water. A flow rate of 100 ft.3/sec. translates to 65 million gallons per day. Larger springs in Florida supply the base flow for many streams and rivers.

What affects spring flow?

Multiple factors can affect the amount of water that flows from springs. These include the amount of rainfall, size of caverns and conduits that the water is flowing through, water pressure in the aquifer, and the size of the spring’s recharge basin. A recharge basin is the land area that contributes water to the spring – surface water and rainwater that falls on this area can seep into the ground and end up as part of the spring’s discharge. Drought and activities such as groundwater withdrawals through pumping can reduce flow from springs systems.

If you haven’t experienced the beauty of a Florida Spring, there is really nothing quite like it. Here in the panhandle, springs such as Wakulla, Jackson Blue, Pitt, Williford, Morrison, Ponce de Leon, Vortex, and Cypress Springs are some of the areas that offer wonderful recreational opportunities. The Florida Department of Environmental Protection has a ‘springs finder’ web page with an interactive map that can help you locate these and many other springs throughout the state.

https://nwdistrict.ifas.ufl.edu/nat/2020/04/09/the-incredible-floridan-aquifer/

Andrea Albertin