The present study deals with the different hydrogeological
characteristics of the coastal region of central Kerala and a comparative
analysis with corresponding hard rock terrain. The coastal regions lie in
areas where the aquifer systems discharge groundwater ultimately into the
sea. Groundwater development in such regions will require a precise
understanding of the complex mechanism of the saline and fresh water
relationship, so that the withdrawals are so regulated as to avoid situations
leading to upcoming of the saline groundwater bodies as also to prevent
migration of sea water ingress further inland. Coastal tracts of Kerala are
formed by several drainage systems. Thick pile of semi-consolidated and
consolidated sediments from Tertiary to Recent age underlies it. These
sediments comprise phreatic and confined aquifer systems. The
corresponding hard rock terrain is encountered with laterites and
underlined by the Precambrian metamorphic rocks. Supply of water from
hard rock terrain is rather limited. This may be due to the small pore size,
low degree of interconnectivity and low extent of weathering of the country
rocks. The groundwater storage is mostly controlled by the thickness and
hydrological properties of the weathered zone and the aquifer geometry.
The over exploitation of groundwater, beyond the ‘safe yield’ limit, cause
undesirable effects like continuous reduction in groundwater levels,
reduction in river flows, reduction in wetland surface, degradation of
groundwater quality and many other environmental problems like drought,
famine etc.Cochin University of Science and TechnologyDept. of Marine Geology and Geophysics
School of Marine Sciences
Cochin University of Science and Technolog