Present status of groundwater quality and quantity related issues and need for a groundwater monitoring system for Sri Lanka

Abstract

Demand for groundwater has grown rapidly as a result of population increase and economic development of the country. A wide variety of users such as small-scale irrigators, households and housing development schemes, industries and industrial promotion zones, hotels, shrimp farms are now tapping groundwater in large quantities. The unlimited groundwater extraction cause depletion of the regional groundwater table and drying out surrounding wells located in the shallow aquifers. The groundwater pollution due to application of excess fertilizer and use of pesticides and other agrochemicals in agricultural areas and emission of wastes from the industries leads to contaminate groundwater sources considerably.Recently, the environmental issues related to groundwater depletion and groundwater pollution is considerably increased in many parts of the country. These areas includes Kalpitiya, Jaffna Peninsula, CKDu prevailing areas in Anuradhapura, Polonnaruwa, Kurunegala, Monaragala, Badulla and Hambantota districts, areas where groundwater based water bottling schemes established and many other coastal areas. Water Resources Board has engaged with research work on groundwater quality and quantity related issues of the above areas and found interesting results. The occurrence of excess amounts of Nitrates, iron, fluorides,phosphates and High EC values in groundwater are the main issues identified in those areas.The paper discuss the current status of groundwater in Sri Lanka with respect to those issues and propose to establish a groundwater monitoring network to manage this valuable resource of the country for future generations.