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After independence, the Government of India assigned top priority to the
sectors of drinking water and irrigation to tide over the recurring
droughts and famine prevailing in different parts of the country.
Ground water investigations in Kerala State were, in the early years, carried out by the Ground water
Wing of the Geological Survey of India (G.S.I.). During the period 1954
to 1960, under the exploration programme called Technical Co-operation
Mission with U.S. assistance, 5 exploratory boreholes were drilled in
Kerala by the erstwhile Exploratory Tubewell Organization (E.T.O.) and
the Ground water Wing of the G.S.I. This was the first ground water
exploration done in the State. Systematic hydrogeological surveys for
ground water were also carried out in the State by the Ground water Wing
of the G.S.I, Hyderabad. During 1969, G.S.I. established an Office in
Trivandrum exclusively for hydrogeological surveys and this was known as
Ground Water District Unit XXI. Subsequently, the Exploratory Tubewell
Organization (E.T.O.) and the Ground water Wing of the G.S.I. were
merged together to form the Central Ground Water Board in 1972. A Unit
Office of CGWB was started in 1978 at Trivandrum under the Southern
Region, Hyderabad. A full fledged Regional Office of CGWB started
functioning in Kerala in 1989 with the jurisdictional power of Kerala
and U.T of Lakshadweep island.
Almost the entire State of Kerala was covered by systematic
hydrogeological surveys by March 1986. An area of 6,129 sq.kms of Tribal
sub-plan area was also covered to identify the sources of drinking water
for the tribal population of the State.
During the first SIDA assisted Ground Water Project (Swedish
Collaboration, 1975-1979) based at Coimbatore, the upper reaches of
Bharathapuzha basin up to Cheruthuruthy were covered (2,150 sq.kms) for
water balance studies. The second SIDA Project (1983-1988), which
covered 11 drainage basins from Vamanapuram in the south to Kadalundi in
the north carried out extensive hydrogeological studies, exploration and
monitoring of ground water regime in the State. During this project, 66
exploratory boreholes and 16 observation wells were drilled in the hard
rock areas of the State. In the sedimentary areas, 6 exploratory tube
wells, 13 piezometers, 4 shallow tube wells and one observation well
were also constructed. The studies in this project brought in valuable
basic data on the nature and parameters of different aquifer systems and
basin-wise areas suitable for ground water development and the number
and type of extraction structures feasible were determined. One
achievement of this project was that a sub-surface dyke (ground water
dam) was constructed at Odakkali in Ernakulam district, which helped
immensely to raise the groundwater level in the upstream side of the
dyke. Pollution studies were conducted in the Alwaye-Cochin industrial
belt and Chavara-Kundara area. It was proved that ground waters in both
the areas were polluted in a localized nature. A methodology was evolved
in this project for selection of bore well sites in the hard rock area |
