The biggest challenge for the next decade or so will be supplying potable water to the growing population of the world, the Johannesburg Earth Summit stated this year. This study is based on the analysis of water supply system of Dhaka city as a case study and tried to find out a solution to meet the demand for potable water.

Water supply in Dhaka city is based on surface and groundwater sources. Dhaka Water and Sewage Authority (DWASA) has been supplying water to the city dwellers using these sources however, the growing population of the city is steadily making the supply of water inadequate. Dhaka city’s water supply system has to seek an alternative to meet the growing demand for potable water.

Groundwater source supply system of the city, supplies the major share of water and surface water is abstracted from the neighboring rivers of Dhaka city. The ground water source is unlikely to have an increase in supply of water as interference of wells will deny further installation of wells and Arsenic intrusion is quite probable. Whereas surface water source has limited prospect in supplying water as pollution is increasing in the rivers (Buriganga’s chemical health is the greatest example). An alternative should be sought to solve the problem.

The study analyzed the population trend of the city and drawn a population projection till 2020. The growing demand is hence calculated. Review of existing water supply system showed that DWASA is lacking in meeting the current demand for potable water. The grown future demand will have a severe water crisis in the city and alternative must be sought for that reason.

The study also showed rainwater as a highly prospective alternative, which will be able to serve as an alternative source to meet the growing demand of Dhaka’s population. The study has started the hunt for alternative sources of water supply and has opened the door for further research in this area exploring storage and supply prospects of rainwater as a possible further development.