Author(s): I. White; A. Falkland; T. Fatai
Linked Author(s): Ian White
Keywords: Groundwater; Vulnerability; Water pollution; Climate variability; Water legislation
Abstract: Two thirds of the population of the Kingdom of Tonga, live on the small, South Pacific raised limestone island of Tongatapu. Groundwater is the principle source of reticulated fresh water both in the capital Nuku'alofa and in rural villages and is sourced from a relatively thin, fresh groundwater lens overlying seawater. This paper describes a comprehensive, integrated assessment of the vulnerability of fresh groundwater in Tongatapu. Water resources policy and legislation, and the organisation structures for regulating and managing of water were examined. Threats to groundwater from seawater intrusion, overpumping, agriculture, waste disposal, industry, quarrying, urban settlements, population growth, droughts and climate change were analysed using existing data and field measurements. The impact of pumping on freshwater salinity is clearly discernible within ENSO signatures. Suggestions are made for improving the protection of water resources, mitigating saline water impacts, enhancing freshwater supplies and for reforming regulation and management.
Year: 2011