Bangladesh is faced with multiple water quality and quantity problems (such as salinity, groundwater depletion and natural arsenic contamination of groundwater) along with regular natural disasters, such as cyclones and floods. Available options for providing safe drinking water include tubewells, traditionally dug wells, treatment of surface water, desalination of groundwater with high salinity levels, and rainwater harvesting.
Only 56% of the population was estimated to have access to adequate sanitation facilities in 2010. A new approach to improve sanitation coverage in rural areas, called the community-led total sanitation concept, has helped to increase the sanitation coverage. Basic sanitation was available to 59.3% of the population as of 2022. progress for basic sanitation have been considered too slow by Joint Monitoring Programme for Water Supply and Sanitation (JMP)
Bangladesh has a low level of cost recovery due to low tariffs and poor economic efficiency, especially in urban areas where revenues from water sales do not cover operating costs.
Water resources
Surface water Bangladesh has an enormous excess of surface water during the summer monsoon (June to October) and relative scarcity towards the end of the dry season in April and May. Internal renewable water resources are about 105 km3 per year, while inflowing transboundary rivers provide another 1,100 km3 annually (average 1977–2001). Bangladesh heavily depends on the flow of the Brahmaputra, Meghna and Ganges river basins that originate in India, Nepal and China. Whereas deforestation and flood control in the upstream catchment areas increase the flood peaks in Bangladesh, water withdrawals and water diversions may result in water shortages in the dry season. The Ganges Water Sharing Treaty between India and Bangladesh, signed in 1996, allows Bangladesh to receive a minimum amount of during the dry season.
While surface water is hardly used for drinking purposes in rural Bangladesh, ponds have a special significance in rural culture and are preferred for cooking, washing and bathing.
Bangladesh faces various water pollution issues mainly caused by pollutants, bacteria, and pesticides.
Groundwater In rural areas, more than 97% of the population relies on groundwater for its drinking water supply. In Dhaka, 82% of the water supply is extracted from groundwater that is free of arsenic, while three surface water treatment plants provide the remaining 18%. Groundwater is being severely depleted in Dhaka, where the groundwater levels are dropping two to three metres every year. The city's water table has sunk by 50 metres in the past four decades, and the closest in the near South Africa underground water is now over 60 meters below ground level.Institute for Water Modelling, 2009 The Asian Development Bank estimated in 2007 that by 2015 a severe supply shortage would occur if the utility did not reduce groundwater extraction.
Despite the growth of public and private tubewells, achieving drinking water security remains a challenge due to naturally occurring arsenic and salts in groundwater. Bangladesh has highly productive aquifers within the unconfined sediments of the Holocene age. However, these geologically young sediments are prone to developing and preserving high concentrations of arsenic, particularly within depths of 30–150 m that coincide with the optimum well depth. Text was copied from this source, which is available under a Creative Commons Attribution 4.0 International License
In general, the groundwater salinity increases from north to south in the country. But even within small areas, the groundwater salinity can vary a lot.
The south-western coastal region (Khulna district) has highly productive aquifers within thick, unconsolidated alluvial sediments. However, the relatively shallow aquifers are usually contaminated by high levels of salts, with isolated freshwater lenses. Text was copied from this source, which is available under a Creative Commons Attribution 4.0 International License Human activities are influencing the availability of the groundwater: there is over extraction of groundwater, reduced upstream river discharge, and inland modification of coastal areas. These activities interfere with the natural hydrology and push the salinity front further inwards. Sea level rise and increased frequency and intensity of cyclones due to climate change, coupled with high population growth, are likely to increase exposure to these salinity risks in the future.
Water use Only about 15 km3 annually, or about 1% of total water resources, is being withdrawn for human use. Out of the total withdrawals, 86% is for agriculture, 12% for domestic water supply, and 2% for industry. It is predicted that Bangladesh's population will increase from 129 million people in 2000 to 181 million by 2025 and 224 million by 2050, accompanied by an increased demand for water.
Piped water supply, as estimated by the utility, was about 100 litres per capita per day in Dhaka in 2007 for those with access to piped water supply. Given the low share of metering, estimates of per capita water use are not reliable. In a sample of 11 cities, 8 did not have any customer metering at all. In Dhaka and Chittagong, 70 and 86 percent of customers were metered. In the city of Rajshahi, which has no metering, the municipal utility estimated per capita water use at 98 litres per capita per day. However, a customer satisfaction survey carried out together with the NGO Forum on Drinking Water Supply and Sanitation carried out among 600 respondents in 2008 found that the average was only 78 litres. Water use varied significantly depending on income, with the poor consuming 43 litres and the poorest only 28 litres. The survey also showed that half the respondents drank water straight from the tap without filtering or boiling it, while 27% rated the water quality as poor.
The estimated amount of water consumed varies significantly between cities. For example, in 2006–07 it was estimated at more than 250 litres in Manikganj, but at only 33 litres in Chapai Nawabganj and Gazipur. The average for 11 cities was 88 litres.
Types of water sources In areas where groundwater is too high in arsenic or too saline, alternative sources and technologies are in use. This includes pond sand filters, rainwater harvesting, small-piped schemes, managed aquifer recharge, and reverse osmosis systems. However, rainwater harvesting is not available all year round. Pond sand filters do not consistently meet water quality requirements.
Desalination plants can be fed from rivers or from shallow tubewells. The lower the salinity of the source, the lower the energy consumption. Reverse osmosis-based desalination plants are gaining popularity in coastal Bangladesh, with both the government and NGOs promoting this technology since the early 2010s. These plants have a production capacity of about 20–60 cubic metres per day and mainly purify brackish shallow groundwater by passing it through a semi-permeable membrane.
Access
Access to drinking water The Bangladesh Bureau of Statistics (BBS) conducted a Multiple Indicator Cluster Survey (MICS) in Bangladesh in the first half of 2019."Bangladesh MICS 2019: Water Quality Thematic Report", Government of Bangladesh, Bangladesh Bureau of Statistics, and UNICEF, 2021. It covered all 64 districts in the eight divisions of Bangladesh. The survey determined that nearly everyone (98.5 percent) had access to improved drinking water sources in 2019. For 86 percent of the households, it was a tubewell that they used as a source of drinking water. Tubewells and other groundwater-based technologies do not necessarily indicate the extent of safe drinking water supply in Bangladesh. This is due to the country's complex hydrogeologic settings with high spatial variability of groundwater salinity risks, and without any monitoring of salinity.
When taking into account more than just access, the situation is not as favourable: "Safely managed drinking water [...] was accessible to 42.6 percent of the population, with water quality being the main limitation". Here, safely managed drinking water is defined as "the use of an improved drinking water source which is located on premises, with sufficient drinking water available when needed, free of faecal (E. coli) and priority chemical contamination (arsenic below the national standard)".
In June 2019, the Department of Public Health and Engineering (DPHE), the national lead agency for provision of rural water supply, reported a total of 1.8 million waterpoints, of which 91% were functional. These waterpoints included 1.27 million shallow and 0.47 million deep tubewells, while the remaining are split between pond sand filters, ringwells and rainwater harvesting systems. Tubewells serve as the main source of drinking water in rural Bangladesh, with access to water for rural populations increasing from 65% in 1990 to 97% in 2015.
In 2015, 87% of the population had access to "improved" water, and the figure was identical to rural and urban areas. In 2015, there were still around 21 million people lacking access to "improved" water.WHO/UNICEF (2015) Progress on sanitation and drinking water - 2015 update and MDG assessment , Joint Monitoring Programme for Water Supply and Sanitation. pp. 56–57.
Access to sanitation Data from 2019 showed that 64.4 percent of the population have access to improved sanitation. Socio-economic demographics and geography determine if this access figure is higher or lower for a given area. This figure had gone up slightly from 2015 when it was reported that 61% of the total population had access to improved sanitation.
When looking at the more stringent parameter of "proportion of the population with access to safely managed sanitation" the value is a bit lower, with 58.9 percent. This might even be an overestimate as the data for tracking faecal sludge management is unreliable. Low levels of WASH access can be associated with stunted growth and diarrhoea in children.
Data from 2010 and earlier Since arsenic was discovered in Bangladeshi groundwater in 1993, the share of the population with access to safe drinking water had to be adjusted downward. Access to an improved source of water supply increased only slightly from 77% in 1990 to 81% in 2010, whereas coverage of improved sanitation increased from 39% to 46% during the same period.* Data are based on
As of 2010, 67% of Bangladeshis had a permanent water source, and a majority of them used tube wells.
Estimates of access to an improved source of water supply are greatly affected by the presence of arsenic in groundwater, which is estimated to affect 27% of all wells and is subtracted from the figures obtained by solely measuring the level of access to infrastructure. Without taking into account the presence of arsenic, 99% of the urban population and 97% of the rural population actually had access to an improved source of water supply according to the Demographic and Health Survey of 2004, which is an unusually high level of access for a low-income country. In urban areas, access was found to be as follows: 68% tubewells, 23% piped inside dwelling, and 8% piped outside dwellings. In rural areas, the breakdown was: 96% tubewells, more than 2% ponds, lakes and rivers, 1% dug wells, and less than 0.6% piped inside and outside dwellings.
Rainwater harvesting, although practised in Bangladesh, was not included in the survey. The figures for access to water and sanitation, taking into account the presence of arsenic, are as follows for 2010:
Access to Water and Sanitation in the Bangladesh (2010) Urban(28% of the population) Rural(72% of the population) TotalWater Broad definition 85% 80% 81% House connections 20% 1% 6%Sanitation Broad definition 57% 55% 56%Sewerage n/a n/a n/a
Access to water at schools