EXCAVATIONS IN GROUND WITH SUB-SOIL WATER.

Excavations of foundation trenches in ground having high water table, or in water-logged area pose great problems because of water oozing in the trench from sides, bringing with it the soil from the sides. The timbering, if provided, would become loose and collapse. Excavatíons can be carried out by dewatering the sub-soil water. Foundation dewatering can be done by the following methods:

(i) Ditches and sumps 
(ii) Well point system
(iii) Shallow well system
(iv) Deep well system
(v) Vacuum method.
and (vi) Electro-osmosis method.