Chittagong Port Authority has set up a desalination surface water treatment plant for Tk 24 crore, aiming to become self-dependent for water supply.
The contractors, Dhaka-based ABM Water Company and Italy's Oltremare, will start water purification at the plant today on a trial basis.
CPA needs 6,000 tonnes of water a day, 40 percent of which is obtained from the Water Supply and Sewerage Authority.
Once the plant is up and running, it will produce 8,800 tonnes of drinking water a day, enough to meet CPA's daily consumption, its Chairman Nizamuddin Ahmed said, adding that the additional water can be supplied to others or be used for commercial purpose.
The purified water will be similar to the World Health Organisation-defined standard, he said, adding that the plant will be formally inaugurated in the middle of this month.
Water from Karnaphuli river will come through a two kilometre-long pipe to the plant area, where it will be made drinkable through various steps of purification.
The river's water is tainted with salinity, dust and oil and the ratio of TDS (total dissolved solids) in the water ranged between 3,000 and 29,000 a litre, said AKM Ataul Korim, chairman of ABM Water Company. The TDS are the compounds in the water that cannot be removed by a traditional filter.
Korim said the permissible ratio of TDS for drinkable water is 1,500 in coastal areas, while it is below 1,000 in non-coastal areas. In bottled mineral water, the TDS ratio is 200 to 250, he said.
The TDS will be brought down to less than 200 in the plant at Chittagong port, he said, adding that the plant will be the largest of its kind in the country.
Many donor agencies and non-government organisations in coastal areas set up desalination surface water treatment plants, but not in a big way like CPA, Korim said.
The capacity of water purification in the port's plant will be 9,600 tonnes a day, but the port authority will not utilise the full capacity right now, he said, adding that they will hand over the plant to the CPA by the middle of this month.
The Chittagong Port is the principal seaport of Bangladesh that handles about 92 percent of the country's export-import trade.