According to practical suggestion given by A.Casagrande, every transition in the shape of curve is smooth, being either elliptical or parabolic in shape.

Complete design of dewatering system consists of the diameter and spacing of well points or wells, penetration of wells and the pumping capacities.

The portion between any two successive flow lines is called a flow channel and the portion enclosed between two successive equipotential lines and successive flow lines are known as field.

The graphical method of flow net construction first given by Forchheimer in 1930, based on trial sketching.

The application of electro-osmosis to dewatering of soil was largely developed by L. Casagrande.

ie =Δ h /l, represent gradient formula where Δ h=potential drop and l is the average of last field in the flow net at the exit end.

EA= extra length factor, which is a function of the ratio of slot penetration p to the thickness of pervious stratum b.

A flow net can be utilized for determination of seepage, seepage pressure, hydrostatic pressure, and exit gradient.

The flow lines and equipotential lines always meet at right angles to one another.

Using the formula, hW = h -Z