Risks of climate change, operation and management on climate resilient water supply options in the coastal areas of Bangladesh

The coastal areas of Bangladesh are regarded as the most vulnerable region in the country due to climate change impact. Majority of the coastal population depend on water supply from rainwater harvesting (RWH) systems, pond sand filters (PSF) and rain-feed ponds. These water supply options are considered as climate resilience water supply options; however these will be seriously impacted by climate change induced tidal surge and cyclone, salinity intrusion, drought and excessive rainfall. This study was conducted to explore the operational and maintenance issues of these water supply options and the associated microbial health risk and also the possible climate change impacts on these water supply options. It reveals that both management and operational related issues contributed to microbial risk factors of ponds and PSFs water; whereas for rainwater harvesting systems, maintenance issues contributed the major risk factors. Water from all these options was found microbiologically contaminated and is not safe for drinking without further treatment. It also reveals that both pond and PSF water will be seriously impacted by storm surge and cyclone and salinity intrusion. RWH systems are found to be more resilience against climate change induced impacts and thus will be more effective. Both technical and social adaptation measures should be undertaken for a sustainable water supply in the coastal areas of Bangladesh.