1. Watersheds and Water Resources: Vol 2: Groundwater

2. I. Water Resources & Hydrology

3. A. Hydrology & Surface Water
Most cities rely on the nearest river, lake or reservoir to meet their need for fresh water.

4. B. Hydrology & Groundwater
Groundwater provides the largest source of usable water storage in the United States.
Underground reservoirs contain far more water than all surface reservoirs and lakes, including the Great Lakes. In some areas, groundwater may be the only option.

5. Most water is underground…
II. Aquifers!

6. A. Aquifer Structure
Aquifer- a saturated layer of porous rock material that lies on top of impermeable rock.
Aquifers are more like underground sponges, absorbing all the water percolating through the soil, than
they are like
underground
lakes.

7. 3. Water Table

8. A. Aquifer Structure 3. The water table is the top of an aquifer.
It is the line between soil that is saturated with water, and soil that has air spaces.

9. B. Groundwater Exchange
In a recharge zone, the water table is deep and water is actively entering and filling an aquifer.
In a discharge zone, the water table is shallow and water is leaving the aquifer to fill swamps, lakes, streams, etc.

10. True or False?
Most cities rely on surface water to meet their water needs.
Aquifers are like large lakes below the surface.
The water table is the bottom of an aquifer.
Barton springs is filled by the water from Edward’s Aquifer. This part of the aquifer is a recharge zone.
Here in Round Rock/Georgetown we have to properly dispose of motor oil and paint because we are part of the Aquifer’s recharge zone.