Aquifers are underground layers of rock and sand that hold water. These layers are made up of loosely packed sediments and layers of calcium-rich limestone and dolomite. In Florida, most of the population depends on the Floridan aquifer for their drinking water. The Floridan aquifer, which is the largest and deepest aquifer in the state, holds groundwater like a sponge. Holes in the rock that make up the aquifer allow the water to move freely through it. Aquifers are replenished from rainwater that soaks into the ground.
