Groundwater and Aquifers Overview

Infiltration is the process where water seeps into the ground and fills the pores and cracks of soil, sediment, and porous rocks.
Water percolates downward until it reaches an impermeable layer of rock, such as shale and clay, which hinders or prevents groundwater movement.

Definition: Depressions or areas below the surface containing at least one layer of impermeable rock that retains water.
Water Entry: Water enters aquifers primarily by infiltration from precipitation, leakage from lakes/rivers, and excess irrigation.

Unconfined Aquifer
- Only has an impermeable bottom layer.
- Top layer is typically soil, allowing relatively easy access to water.
Confined Aquifer
- Surrounded by two impermeable rock layers but can have specific recharge zones where water enters.
- Water removal is more difficult due to two barriers and requires wells to extract water.

Recharge Area: Surface land area that collects water, allowing it to infiltrate into groundwater.
Water Table: The dynamic top level of the saturated zone in an aquifer; varies with environmental conditions.
Saturation Zone: The area of the aquifer that is saturated with water and below the water table, expanding and contracting with water levels.
Unsaturated Zone: Also known as the Zone of Aeration; located above the water table and consists of soil where plant roots extract water. It includes a capillary fringe, which is in contact with the water table.

Florida consists of several sequences of aquifers:
- Surficial Aquifer: The uppermost aquifer, supplying drinking water to parts of Florida.
- Biscayne Aquifer: A shallow aquifer beneath Miami-Dade, Broward, and Palm Beach counties, crucial for South Florida's water supply.
- Floridan Aquifer: The largest and deepest aquifer, extending from Georgia/Alabama to South Florida; primarily used in North Florida.

Springs are natural openings in confined aquifers where water flows out due to internal pressure.
Their significance: Springs contribute to drinking water availability and local ecosystems.
Human impact includes the diversion of water sources and changes to natural land, which can lead to run-off and decreased aquifer recharge.

The Biscayne aquifer experiences altered recharge patterns due to human activity, with canals diverting water away from natural recharge areas.
Manmade infrastructures often replace natural environments, limiting water infiltration.
The region faces challenges with saltwater intrusion due to over-extraction from coastal wells, reducing freshwater availability and requiring reliance on alternative water sources.
As Florida’s population continues to grow, water usage and sustainability will become major challenges for the state.