STRIP DRAIN FUNCTIONS
1. Filter and drain off the water present in the earth.
2. Speed up the reduction in hydrostatic pressure in the earth
3. The water rises through capillary action as far as the INTERDRAIN drainage blanket.
INTERDRAIN (GMG) FUNCTIONS
1. Intercepts and drains off the infiltrated rain water.
2. Cuts off capillary ascent from the strip drains.
3. Drains off the water towards the sides.
4. Anti-pollution layer of fines.
VIADRAIN FUNCTIONS
1. Collects the water from INTERDRAIN and drains it into the drain pipe fitted at the bottom.