Effects of a Tropical Cyclone on the Drinking‐Water Quality of a Remote Pacific Island

Abstract

The effect of a cyclone (Ami, January 2003) on drinking-water quality on the island of Vanua Levu, Fiji was investigated. Following the cyclone nearly three-quarters of the samples analysed did not conform to World Health Organisation (WHO) guideline values for safe drinking-water in terms of chlorine residual, total and faecal coliforms, and turbidity. Turbidity and total coliform levels significantly increased (up 56 and 62 per cent, respectively) from pre-cyclone levels, which was likely due to the large amounts of silt and debris entering water-supply sources during the cyclone. The utility found it difficult to maintain a reliable supply of treated water in the aftermath of the disaster. Communities were unaware they were drinking water that had not been adequately treated. Circumstances permitted this cyclone to be used as a case study to assess whether a simple paper-strip water-quality test (the hydrogen sulphide, H(2)S) kit could be distributed and used for community-based monitoring following such a disaster event to better protect public health. The H(2)S test results correlated well with faecal and total coliform results as found in previous studies. A small percentage of samples (about 10 per cent) tested positive for faecal and total coliforms but did not test positive in the H(2)S test. It was concluded that the H(2)S test would be well suited to wider use, especially in the absence of water-quality monitoring capabilities for outer island groups as it is inexpensive and easy to use, thus enabling communities and community health workers with minimal training to test their own water supplies without outside assistance. The importance of public education before and after natural disasters is also discussed.

Temporal and thematic trends in water, sanitation and hygiene (WaSH) research in Pacific Island Countries: a systematic review

“…At first glance, this seems a reasonable bias in a tropical region with high average temperatures, limited area for surface water capture and limited freshwater resources on scattered landmasses surrounded by ocean. However, as highlighted in a number of the studies reviewed here, improper or inadequate sanitation poses a serious contamination threat to an already-limited freshwater supply (Merson et al 1977;Mosley et al 2004;Fujita et al 2014), and increases the vulnerability of a community already relying on a finite water source. Poor hygiene has also been flagged as a leading vector of disease transmission in PICs (Bukenya & Nwokolo 1990;Greenwell et al 2013), and yet trails in the number of studies performed.…”

“…Large storms threaten public health in PICs when WaSH infrastructure is overwhelmed by high-tides and torrential rains that also contaminate freshwater with raw excreta (Mosley et al 2004). The rainy season was found to coincide with peak prevalence of infections including Salmonella spp.…”

“…Many WaSH interventions reported in the literature are responses to extreme weather (floods, droughts and cyclones) or damage to WaSH services, with the vast majority focusing on the immediate delivery of safe water supplies to affected communities (Finau et al 1986;Mosley et al 2004;White et al 2007). …”

“…The impacts documented ranged from catastrophic loss of whole villages, through destruction of water and sanitation infrastructure, to changes in source water quantity and/or quality (Mosley et al 2004;White et al 2007;Keim 2010). Studies have examined aquifer contamination from storm surge in atoll communities (Keim 2010; and changes in water quality across rainwater tanks, wells and streams (Terry et al 2001;Horak et al 2010).…”

Vulnerability assessment for loss of access to drinking water due to extreme weather events

“…Specifically, droughts can cause both a decrease in water supply as well as salinization and increased pollutant concentration due to a reduction in both contaminant mobilization and dilution effect (IPCC 2008); floods and cyclones can cause physical damage to infrastructure from floodwaters and high-velocity winds, respectively, as well as contamination of water supplies from the introduction of debris, silt, pollutants, and sewage (Islam et al 2007;Kistemann et al 2002;Mosley et al 2004). These extreme weather event types are projected to increase in intensity and/or frequency by the Intergovernmental Panel on Climate Change (IPCC) as a result of global climate change (IPCC 2013).…”