Groundwater

1
Lecture 13 Groundwater
2
Lecture Outline
I Porosity and Permeability II The Water
Table III Movement of Groundwater A) Hydraulic
Head and Gradient B) Darcy's Law C) Fluid
Potential IV Aquifers V Wells VI Springs and
Streams VII Effects of Groundwater VIII Groundwate
r Contamination IX Conclusions
Lecture 13 i
3
Distribution of Earth's Water
4
Porosity
the ratio of aggregate volume of opening in a
rock or soil to its total volume. usually
expressed as a percentage.
5
Permeability
the capacity of a porous rock or soil for
transmitting a fluid
6
Porosity and Permeability
7
The Water Table
8
Water Table Seasonal Fluctuations
9
Groundwater Flow

• water pressure
• elevation

10
Groundwater FlowHydraulic Head and Hydraulic
Gradient
hydraulic head (h) elevation (z) pressure (p)
hydraulic gradient Dh/L
11
Groundwater FlowVelocity - Darcy's Law
12
Aquifers
13
Wells
14
Wells
15
Wells
16
Wells
17
Springs
18
Springs
19
Gaining Streams and Losing Streams
20
Balancing Withdrawal and Recharge
21
Balancing Withdrawal and Recharge
22
Effects of Groundwater

• Caves
• Sinkholes
• Karst Topography

23
Effects of GroundwaterCaves
24
Effects of GroundwaterSinkholes
25
Effects of GroundwaterKarst Topography
26
Effects of GroundwaterKarst Topography
27
Groundwater Contamination
28
Groundwater Summary