Groundwater WASH Nexus in Asian Cities: Hanoi, Kathmandu, Khulna

This working paper assesses the groundwater-WASH (Water, Sanitation and Hygiene) nexus based on an analysis of domestic water uses in three groundwater dependent Asian Cities: Hanoi (Viet Nam), Kathmandu (Nepal), and Khulna (Bangladesh). The paper analyses the pull (benefits) and push (constraints) factors for use of groundwater by residents in these cities based on five decision criteria: preference, access, adequacy, affordability and quality.
The study has found a close linkage between groundwater and WASH. Groundwater plays a critical role in improving access to WASH in the three cities. The study finds that groundwater is one of the primary choices or the only source of water for residents in the studied cites. Access to groundwater was the primary pull factor in all cities to overcome the water supply deficit resulting from a lack of piped water connection or unreliable supply. Poor groundwater quality was the major push factor identified in all the cities. Due to quality concerns, residents were reluctant to use groundwater for direct consumption. Groundwater was therefore mostly used for sanitation (toilet flushing) and maintaining hygiene (bathing, washing, and cleaning). Cost was both a push and pull factor depending on the amount of water used by a family. For low volume use in households (<100 litres/person/day), a cheap hand-pump or a dug well was a major enabling factor (i.e., pull factor), whilst for high use households (>100 litres/person/day) groundwater was found to be more expensive than tap water (i.e., push factor).
All the cities have a plan for or have already introduced new surface water supply systems to boost the coverage and quality of water services. This is a step towards finding a long-term solution to water shortages and will reduce the pressures on groundwater. However, due to an increasingly uncertain water supply, groundwater still holds the key to city water supply security. Cities should therefore find ways to make tap water and groundwater affordable in order to balance the excessive reliance on one source over another and to raise the profile of groundwater in the city’s water security planning. Further efforts will be needed to avoid groundwater contamination and increase the quality of groundwater for consumption in addition to ensuring its continued availability for sanitation and hygiene. Any development of WASH services should incorporate safeguard measures to prevent likely depletion of the water table and degradation of water quality. Cities in Asia could consider alternative pricing policies and use stronger regulatory measures to minimise unplanned development of their groundwater resources, control wasteful use of water, and promote a culture of safe disposal of waste, wastewater, and harmful chemicals.