"We have to shift the intake point four to five kilometres away from existing point of intake, which is near Balu river, as the water of Shitalakhya is being polluted by factory and human waste through Balu river," said a high official of Wasa.

The change will be made for the first and second phase of the water treatment plant project. Danida and Swedish SIDA have already agreed to fund the second phase which will cost Tk 600 crore. Originally the cost was estimated at Tk 250 crore but it will take another Tk 350 crore to install pipes and other facilities for a 5-km long intake pipe.

A team of foreign experts, which worked at the spot until Eid, will prepare a report on the second phase soon, said the Wasa official.

The Sayedabad Water Treatment Plant was constructed to use surface water from Shitalakhya reducing the dependency on groundwater. Its second phase was designed at the time when the first phase started in 1996.

The plant, jointly funded by the governments of Bangladesh and France and the World Bank, uses water from the Shitalakhya. After a feasibility study in 1990s, the river was selected because of its easy access to the plant and quality of water.

But the Shitalakhya is now being polluted by the Balu river, which is polluted by industrial waste of the city. The Sayedabad Water Treatment Plant receives Shitalakhya water from the point where Balu river meets Shitalakhya.

The plant which started operations in July 2002, provides 22.5 crore litres of water daily, which meet 15 percent demand of the city residents. The second phase will provide another 22.5 crore litres to raise the percentage to 30 percent.

The present water demand in the city is 200 crore litres of which 150 crore litres are being supplied from deep tube-wells and the treatment plants. The Chandni Ghat treatment plant provides 4 crore litres a day.

The main source is underground water lifted by deep tube-wells. Dhaka Wasa supplies 124 crore litres water from underground and the rest from surface sources.

Wasa observed that the water quality of the Shitalakhya and Buriganga is gradually deteriorating due to dumping of wastage. Therefore, it has become necessary to find new sources of surface water for treating in the plants.

Officials said Wasa had earlier planned to take surface water from the Padma for its Pagla plant estimated to cost about Tk 1700 crore. The Padma water would be used in this plant for Dhaka City after pumping it at Mawa point.

The proposed Pagla water treatment plant to be constructed with Chinese assistance would provide another 45 crore litres of water a day.