12-Groundwater Perspectives of Small Islands -Lakshadweep Islands, India.

Abstract

Hydrological perspective of small islands is low and scarce. All the atolls of Lakshadweep islands and more than five hundred islets/islands of Andaman and Nicobar islands are of the group of small and low islands. The size of the biggest island (Androth) in Lakshadweep is less than 5 sq.km and the smallest (Bitra) is less than 1 sq.km Ground water is the major component of the water balance in Lakshadweep islands and majority of the Andaman and Nicobar Islands. Lakshadweep islands consist sandy soils with high permeability. Sandy soil with high permeability may also genesis submarine groundwater discharge. The availability of fresh water resources of two islands Kavarathi and Bengaram of Lakshadweep islands were estimated using Ghyben-Herzberg equation for oceanic island, and impact of sea level rise were estimated using Brunn's rule. Seasonal fresh water fluctuations in the observation wells were measured from Kavarathi and Bengaram islands. The intrusion of saline water and its seasonal variation were surveyed and estimated. The present study consists of scenario of ground water, impact of sea level rise on coastal aquifer, the present utilization of ground water and problems related to submarine groundwater discharge of small islands.