---
title: "Groundwater — AP Environmental Science Definition"
description: "Groundwater is water stored in saturated underground aquifers. It's a small but critical reservoir in the hydrologic cycle (Topic 1.7) and a major drinking water source on the APES exam."
canonical: "https://fiveable.me/ap-enviro/key-terms/groundwater"
type: "key-term"
subject: "AP Environmental Science"
---

# Groundwater — AP Environmental Science Definition

## Definition

Groundwater refers to the water present beneath Earth's surface in saturated zones called aquifers. It is an important source of drinking water and supports ecosystems.

## Related Study Guides

- [1.6 The Phosphorous Cycle](/ap-enviro/unit-1/phosphorus-cycle/study-guide/JujZhatUDATN9fbpaIv9)
- [1.7 The Hydrologic Cycle](/ap-enviro/unit-1/hydrologic-cycle/study-guide/Mnp6Jfh7MANP2YtOhxCb)

## Review

### Related Terms

- Water Table: The upper boundary of the zone of saturation where groundwater fills all available spaces in soil or rock.
- Recharge Area: A location where water infiltrates into an aquifer, replenishing its supply.
- Cone of Depression: A cone-shaped lowering of the water table caused by excessive pumping from a well.