Unfortunately, this means that contamination is often widespread before being detected. Even if release of the contaminant is stopped, it may take many years for an aquifer to purify itself naturally. Springs are created when groundwater naturally flows to the surface. Groundwater discharged from a spring may have traveled many miles before reaching the surface. Usually, spring water discharges occur or increase when rain has recharged the groundwater system in upland areas.
Springs occur throughout the state, but are most abundant in north central Florida.
These are also the largest springs which may discharge several million gallons per day into local rivers. For more information, go to the Special Feature on springs. Sinkholes are closed depressions in the land surface formed by dissolution of near-surface rocks or by the collapse of the roofs of underground channels and caverns. Sinkholes are a natural, common geologic feature in places underlain by soluble rocks such as the limestone and dolomite that form the Floridan aquifer system. Under natural conditions, sinkholes form slowly and expand gradually.