GSDA is implementing schemes to improve the performance of the existing ground water sources and strengthening the sources by unconventional measure.
Sources strengthening by unconventional measures as on today
Principle and general description of the above technique is given below.
1. FRACTURE SEAL CEMENTATION
The groundwater migration through a network of shallow depth aquifer from the discharging location is arrested by this technique. It is suitable in disintegrated rock combined with fracture and granular porosity. After identifying the suitable area on the basis of geohydrological investigations, this technique is adopted. Under this process, normally one or two rows of suitable diameter boreholes are drilled to a depth of a little more than the deepest dug well in the command area of stream or all. These rows across the stream are filled by injecting cement slurry under high pressure for sealing of existing fracture. This technique is used to create an effect of “ Cut Off Wall “ as Underground band hard.
2. JACKET WELL
The construction of Jacket well around the dug well in hard rock area increases the effective diameter of the well artificially thereby increasing the storativity. Borewells of about 115 mm diameter and to a depth of open dug well or to a shallow aquifer are drilled around the supply well, either in circular or semi-circular or any other desired pattern depending upon the topographical and hydrological conditions. The blasting of these bores is carried out using slurry explosives, detonating cord and electrical detonators to create fractures and interconnection between the boreholes to increase the effective diameter of supply well and to create additional storativity of water.