...
Since 1993, the Multiple Indicator Cluster Surveys (MICS), with technical support from UNICEF, have gathered data about drinking water and sanitation in Bangladesh. According to their most recent study in 2012-2013, 90.6% of the Bangladeshi population depends on tube wells or boreholes (both groundwater supplies) for drinking water[2]; this accounts for 94.3% of rural households[3]. Despite having access to improved drinking water sources, many Bangladeshis are exposed to poor water quality. The National Drinking Water Quality Survey (NDWQS), published in 2009, found that 22 million households in Bangladesh are drinking water that does not meet the Bangladesh drinking water standard for arsenic. In addition, 41.7% households sampled had a medium, high or very high risk of E.coli in their source water (over 1 cfu/100ml). High iron and manganese concentrations are also major concerns[3]. Microbial water quality studies have not been carried out to date.
Although groundwater quality has been studied extensively in Bangladesh, there is a huge gap in knowledge about surface water quality. A few surface water quality studies have taken place by independent groups, but these usually include costly lab procedures in order to determine water quality parameters. The conclusion of the NDWQS by Carel de Rooy, then UNICEF representative in Bangladesh, is that “strengthening local testing capacity is crucial”[3]. Alternative water sources (such as surface water) that do not pose a threat to human health and can be monitored by local authorities is necessary in order to secure clean, reliable sources of drinking water for the citizens of Bangladesh.
...