Hydraulic potential is a concept that helps describe the tendency of water to move from one area to another. It is the sum of pressure potential, matric potential, and gravitational potential. The factors that affect hydraulic potential are pressure potential, gravimetric potential, and matric potential. Water will freely move from an area of higher total hydraulic potential to an area of lower total hydraulic potential.

1. • Hydraulic potential
• does hydraulic pot. vary in time and space?
• Which are the factors that influence hydraulic pot.
variations?
• Example

2. Hydraulic Potential
• is a concept that helps to describe the tendency of
water to move from one area to another
• It is sum of pressure potential, matric Potential and
gravitational potential.

3. Factors that Affect Hydraulic Potential
• Pressure potential
• Gravimetric potential
• Matric potential
ψh= ψp+ ψm+ ψz

4. Water free to move will move from a region where it has
higher total potential to one of lower total potential. The
potential due to gravity is known as the gravitational potential
ψPA
ψgA
ΨhA
A
B
RL
ψPB
ψgB
ΨhB
ψPB
ψgB
ΨhB
A
B
ψPA
ψgA
ψgA
ΨhB <ΨhA
ΨhB <ΨhA

5. The potential due to to the soil particles by which water move
from one place to other place is the matric potential.
matric potential is the force with which water is held in
soil matrix (soil particles and pore space) and is measured by
tensiometer.
Upward flow
Matric Potential
+
-
ψg
ψhA= ψgA+ψmA
ψhB= ψgB+ψpB
=0
ψhB> ψhA
A
B

6. Depth ψ p ψ m ψ g ψ h
0 0 -200 0 -200
-100 0 -150 -50 -200
-200 0 -100 -100 -200
-300 0 -50 -150 -200
-400 0 0 -200 -200
-500 50 0 -250 -200
-600 100 0 -300 -200
-700 150 0 -350 -200
-800 200 0 -400 -200
-900 250 0 -450 -200
-450. -350. -250. -150. -50. 50. 150. 250
0
-100
-200
-300
-400
-500
-600
-700
-800
-900
Reference Level
Water Table
Hydraulic Potential:
Equilibrium Condition
Matric potential
Gravimetric potential
Pressure component
Hydraulic potential
Ψ mm H2O
Depth
mm

7. Thank you