This report describes the drilling program undertaken during November and December 1997 in the
Pangai – Hihifo and Koulo areas on the island of Lifuka. The purpose of the program was to:
* install seven water salinity monitoring boreholes;
* provide additional training for the Ministry of Works (MOW) drilling crew in the methods used in
the installation of the monitoring system used in this program; and
* instruct the local Tonga Water Board (TWB) staff in monitoring procedures.
Most of the 3000 inhabitants of Lifuka live in four contiguous
villages and have been supplied with water from a well in the middle
of the island since 1976. On commencement of operation, the water
rapidly became too salty for human consumption. The majority of the
island is low-lying and consists of highly porous, uplifted coral
limestone. Hydrogeological assessment found the fresh-water lens to be
very thin and strongly influenced by tidal mixing, sea level changes and
drought. Comparison with the morphology of Bermuda led a search for
e conuence of climate change and seismic events has created signicant environmental problems in
Lifuka, an island of 2,400 people (2011 Census) in Tonga’s Ha’apai Group. e subregion experienced an
earthquake on 3 May 2006 that measured approximately 7.9 on the Richter scale. It resulted in subsidence
of 23 cm of Lifuka Island, eectively creating instant sea-level rise. Erosion had already been already been a
problem on Lifuka for some decades; in the past 40 years, Lifuka has experienced signicant coastal erosion
In December 1998, Phase Two of the groundwater pollution study in Tonga was completed. This
Report summarises the activities undertaken to complete the study and presents the outcomes. The
Report relates to the conclusion of field studies commenced in June 1997 that were not completed at
that time due to lack of funds. Field studies, laboratory work and preparation of the results for this
completion of the Phase Two were conducted between August and December 1998
Active participation from people is key to the success
of Integrated Water Resources Management (IWRM).
The purpose of these guidelines is to support
government departments and organisations in
mobilising people towards IWRM.
Active participation from people is key to the success
of Integrated Water Resources Management (IWRM).
The purpose of these guidelines is to support
government departments and organisations in
mobilising people towards IWRM.
Access to safe drinking water is a basic need and is one of the most important contributors to public health and to the economic health of communities. Pacific island countries have yet to overcome the challenge of providing a safe and adequate supply of drinking water to its populations. Infectious, waterborne diseases, such as Typhoid and Cholera and newly emerging pathogens are a major cause of morbidity and mortality within the Pacific region.
An analysis is made of the groundwater resources of Tongatapu Island. The Ghyben-Herzberg approximation is used to estimate thicknesses of a fresh-water lens floating on seawater. Finite-difference calculations are used to estimate rainfall recharge rates, and calculations are made to investigate the dispersion of chloride ions across the fresh-water-sale-water interface. These calculations suggest that artificial recharge might be useful devise to control chloride concentrations in the fresh-water aquifier.
This report acts as a background paper on the current status of wastewater and sanitation in Tonga.
It was based on an independent review of available literature and stakeholder consultations
conducted from 4 – 8 August (refer to annex 1 for agencies/representatives consulted).
Over the past 40 years, investigations in Tongatapu have identified a number of natural and
human-related factors that increase or have the potential to increase the vulnerability of fresh
groundwater sources. Some of these studies have suggested strategies to lessen impacts and
improve resilience. This project builds on the considerable weight of those results as well as the
depth of local expertise and the valuable, long-term record of monitoring. Our aim here is to