1. SubSurface Irrigation

3. q EQUIVALENT K FOR VERTICAL FLOW D = D1 + D2 +...+DnH1 H2 H3 Hn
Hn+1 K1 K2 Kn D1 D2 Dn q
When flow is perpendicular to a series of soil layers, the flux through each layer is the same.
D = D1 + D Dn

4. L EQUIVALENT K FOR HORIZONTAL FLOW Ha Hb
When flow is parallel to a series of soil layers, the discharge through unit thickness of the system is the sum of the discharges through the layers.. K1 D1 Q1 K2 D2 Q2 Kn Dn Qn

5. Hooghoudt Equation m de d S
IMPERMEABLE LAYER

6. Subsurface Drainage Equationy0 m de d S
IMPERMEABLE LAYER

7. Estimating Spacing using The Drainage Equation
DC = Drainage Coefficient

8. Estimating Spacing using The Sub Irrigation Equation
IC = Irrigation Coefficient