Groundwater The Unseen Part of the Water Cycle

1
GroundwaterThe Unseen Part of the Water Cycle
Ground Water Reservoir
Salt Groundwater
2
Who Uses Groundwater?In Northwest Ohio
3
Ohio Groundwater Law

• 1843 Acton v. Blundell English Rule
• The landowner can pump groundwater at any rate
  even if an adjoining property owner were harmed.

• 1861 Frazier v. Brown English Rule in Ohio
• Groundwater is
• occult and concealed
• and legislation of its use is
• practically impossible.

4
Wisconsin Groundwater Law

• 1903 Huber v. Merkel
• English Rule in Wisconsin
• A property owner can pump unlimited amounts of
  groundwater,
• even with malicious harm to a neighbor.

• 1974 Wisconsin v. Michels Pipeline Constructors
  Inc.
• English Rule Overturned
•  
• Landowners no longer have an absolute right to
  use with impunity all water that can be pumped
  from the subsoil underneath.

5
English Rule Overturned in Ohio

• 1984 Cline v. American Aggregates
•  English Rule overturned in Ohio
•  
• Justice Holmes Scientific knowledge in the
  field of hydrology has advanced in the past
  decade so it
•  
• can establish the cause and effect relationship
  of the tapping of underground water to the
  existing water level.

• Today Lingering effects of English Rule
• It is very difficult to prove cause and effect to
  be defensible in court.

6
Most available freshwater is ground water
Atmosphere 0.0001
Streams and Lakes 0.01 (3)
Oceans 97.2
0.61 (97)
7
Porosity and Permeability
Zone of Aeration Water Table Saturated Zone

• Porosity Percent of volume that is void space.
• Sediment Determined by how tightly packed and
  how clean (silt and clay), (usually between 20
  and 40)
• Rock Determined by size and number of fractures
  (most often very low, lt5)

30
5
1
8
Porosity and Permeability
Zone of Aeration Water Table Saturated Zone

• Permeability Ease with which water will flow
  through a porous material
• Sediment Proportional to sediment size
• Gravel?Excellent
• Sand?Good
• Silt?Moderate
• Clay?Poor
• Rock Proportional to fracture size and number.
  Can be good to excellent (even with low porosity)

Excellent
Poor
9
Porosity and Permeability

• Permeability is not proportional to porosity.

30
Table 13.1
5
1
10
The Water Table

• Water table the surface separating the vadose
  zone from the saturated zone.
• Measured using water level in well

Fig. 13.3
11
The Water Table

• Aquifer Saturated sediment or porous rock that
  is sufficiently permeable to supply useable
  amounts of water

Fig. 13.3
12
Groundwater Systems

• Groundwater discharge
• Groundwater leaving the subsurface at
• Natural locations including streams springs and
  wetlands
• Artificial means like pumped wells and drains

13
Groundwater Systems

• Infiltration Precipitation soaking into the soil
  and moving into the subsurface

14
Groundwater Systems

• Groundwater recharge Infiltration percolating to
  the water table

15
Groundwater Systems

• Groundwater Flow
• groundwater moves through the small pore spaces
• from areas with a high water table
• to areas with a low water table

16
Groundwater Systems

• Velocity is proportional to
• Permeability
• Slope of the water table
• Inversely Proportional to
• porosity

Fast (e.g., cm per day)
Slow (e.g., mm per day)
17
Natural Water Table Fluctuations

• Infiltration
• Recharges ground water
• Raises water table
• Provides water to springs, streams and wells
• Reduction of infiltration causes water table to
  drop

18
Natural Water Table Fluctuations

• Reduction of infiltration causes water table to
  drop
• Wells go dry
• Springs go dry
• Discharge of rivers drops
• Artificial causes
• Pavement
• Drainage

19
Effects of Pumping Wells

• Pumping wells
• Accelerates flow near well
• May reverse ground-water flow
• Causes water table drawdown
• Forms a cone of depression

20
Effects of Pumping Wells
Gaining Stream

• Pumping wells
• Accelerate flow
• Reverse flow
• Cause water table drawdown
• Form cones of depression

Water Table Drawdown
Low well
Dry Spring
Cone of Depression
Gaining Stream
Low well
Low river
Pumping well
21
Effects of Pumping Wells
Dry well

• Continued water-table drawdown
• May dry up springs and wells
• May reverse flow of rivers (and may contaminate
  aquifer)
• May dry up rivers and wetlands

Losing Stream
Dry well
Dry well
Dry river