Pumping of Brackish and Saline Water in Coastal Aquifers: An Effective Tool for Alleviation of Seawa

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Pumping of Brackish and Saline Water in Coastal
Aquifers An Effective Tool for Alleviation of
Seawater Intrusion
Mohsen Sherif Civil and Environmental Eng.
Department College of Engineering, UAE
University United Arab Emirates
Anvar Kacimov Department of Soils, Water and
Agricultural Engineering, SQU University Sultanat
e of Oman
23 June 2008
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Seawater Intrusion into Coastal Aquifers
Factors Affecting Seawater Intrusion

• Type of aquifer and its geometry and geology

• Water table and pizometric heads

• Natural rates of flow

• Irrigation and agricultural practices

• Pumping and recharge events

• Rainfall intensities and frequencies

• Seawater concentration and density

• Characteristics and parameters of the porous
  medium

• Geometric and hydraulic boundaries

• Tidal effects

• Earthquakes and vibrational effects

• Others

Which of these factors are important?
It depends on the problem
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Mitigation of Seawater Intrusion

• Inevitable process

• Pumping activities and intrusion rates

Measures to Control Seawater Intrusion

• Reduce the pumping rates
• Reallocation of pumping fields
• Land use and agriculture practices
• Artificial recharge of groundwater
• Use of Scavenger wells

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Objective and Study Domain

• Examine the possibility of reducing seawater
  intrusion by pumping of saline (brackish)
  groundwater.

6 m (asl)
4 m (asl)
4000 elements (5.0 x 2.5 m) 4221 nodes
50 m
H2 4 k (50 y)
Hmax 5.25 m
1000 m
n 0.25, kx 10-6 m2, ky 10-7 m2, a 5 m ?f
1000 kg/m3 , ?s 1025 kg/m3
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Tested Scenarios
6 m
4 m
Steady State equi-concentration lines
Run 1
140 m 105 m
Steady State velocity vectors
5 m
4 m
Reduced hydraulic head at the land side
Run 2
277 m 196 m
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Effect of Pumping
6 m
4 m
Q1
Pumping 86 m3/d Steady state
Run 3
Q1
Q1
Pumping 86 m3/d from two locations at land and
sea side boundaries Steady state
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Effect of Pumping
Q1
Q2
4 m
6 m
Q1 86 m3/d and Q2 130 m3/d Steady State
equi-concentration lines
Run 5
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Pumping from a single well
Basic Run
Group 1 Run 1
Group 1 Run 2
Group 1 Run 3
Group 2 Run 4
Group 2 Run 6
Group 3 Run 7
Group 3 Run 8
Group 3 Run 9
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Thank You