Water sources quality in urban slum settlement along the contaminated river basin in Indonesia: Application of quantitative microbial risk assessment

Abstract

Fecal contamination in water sources is still found globally, especially in urban slum areas of mid-low income countries. Fecal contamination as an indicator of low levels of hygiene and sanitation practices as well as poor management of drinking water supply might increase the risk of waterborne diseases in developing countries like Indonesia. This study aimed to assess quality of all water sources in one of the urban slum settlements along a contaminated river basin in Indonesia. A cross-sectional survey was conducted during the period of August to October 2015. Water samples were taken with simple random sampling from households in urban slum areas along the Cikapundung river basin in the center of Bandung city, Indonesia. Water samples (n=379) from 199 households and 15 common wells were tested for microbiological contamination, and 61 samples of ground water sources and river were tested for selected heavy metal contamination. Annual risk of infection from all water sources was calculated using the quantitative microbial risk assessment. Tap water distribution was poor in this slum area. Most of the dug wells and half of refill bottled water were contaminated. Estimated highest annual risks of infection due to fecal contamination would be caused by dug well and spring water since majority of the households did not use septic tank and disposed human waste directly to the river. Improvement in point-of-use water treatment and storage is essential to prevent risk of waterborne diseases, and tap water should be more accessible and affordable in urban slum areas. The integrated monitoring system to control the quality of refill bottled water production is one of the many essential issues to be prioritized.