To understand the water issues of southwest Florida and the Tampa Bay area, some general knowledge is needed. Florida’s water supply is part of the hydrologic cycle that has repeated itself throughout history and will continue to repeat itself millions of years into the future.

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Here's how the cycle works:

1. As the earth is warmed by the sun, water from the surface (oceans, lakes, ponds, etc.) becomes water vapor and travels into the air. (evaporation).
   
2. When water vapor cools, high in the atmosphere, it forms clouds (condensation).
   
3. The clouds become heavy with moisture (water), then the water falls back to earth as rain (precipitation). In colder climates, this water will fall back down as snow, hail, or sleet. Precipitation helps to replenish surface water bodies, like rivers and lakes, with water.
4. Precipitation, or rain, that falls down to earth moves downward through the openings in the surface/ground (percolation). This helps to put water back into the underground water sources such as springs and aquifers. The water will percolate into the ground through layers of sand, limestone, and rock which filter and further purify it before it is stored underground in an underground layer called the aquifer. In the Tampa Bay area, groundwater is stored in the Floridan Aquifer, a thick sequence of porous limestone considered to be one of the largest aquifers in the nation. It is estimated to contain over a quadrillion gallons of water, equivalent to one fifth of the water in the Great Lakes. The Florida Aquifer varies in thickness from 2,000 feet near the center of the state to only a few hundred feet in coastal areas, and lies beneath most of the state as well as parts of Georgia.
   
5. Water that does not percolate into the ground travels along the surface and helps to replenish surface water bodies with water (runoff).
6. Transpiration also plays a role in the hydrologic cycle. Transpiration is the ability of living things to exhale (breathe) water vapor back into the air. Plants and trees can put an enormous amount of water back into the atmosphere every day.

It is important to realize that the total amount of water in the hydrologic cycle remains the same. It does not diminish; water is neither created nor destroyed in the process. Water is diverted and used, only to be put back into the environment through this continuous cycle.