People suffer as high salinity in Halda water hinders Ctg Wasa plant operations

Excessive salinity in Halda River water has forced the Chattogram Water and Sewerage Authority to stop the operation of its Mohra Water Treatment Plant for a certain period every day, which has caused a decline in water supply for the city people.

Salty sea water is entering the Karnaphuli and Halda rivers during the high tide due to the decrease of water flow from upstream (Kaptai Lake), Ctg Wasa officials said.

But, salinity in the supply water cannot be prevented even by stopping the operation of the plant for a certain period daily. 

City residents have complained of getting salty water from Wasa's supply line, adding water shortages coupled with salty water doubled the sufferings of the residents in the areas for days.

Nurunnabi Khaled, a factory official in the Chattogram EPZ and also a resident of Sabujbagh residential area, told The Business Standard, "We have been getting salty water from the supply line for the last five weeks. We cannot drink it even after purifying. Many people are suffering from diarrhoea."

From the Mohra plant, Chattogram Wasa supplies water to Patenga, South Halishahar, North Halishahar, Sagarika, and Kattoli areas of the port city.

Maksud Alam, the chief engineer of Ctg Wasa, told The Business Standard, "Sea water is entering due to the low water flow from upstream in Karnaphuli. Due to this salinity problem the Mohra plant has to be shut down for a while during low tide, causing a reduction of one and a half crore litres of water production."

"We found a maximum of 1700 mg of saline in Halda water at Ctg Wasa's Mohra plant. According to the Environmental Protection Act, water can be drunk if it contains 150 to 600 mg of salt per litre. We are supplying water to city dwellers, reducing the saline level to 400 mg by mixing groundwater," he added.

Since 1994, city dwellers have been facing this problem almost every year.  In the dry season, when the river doesn't get enough upstream water, it fills the deficit by pulling up saline water from the Bay of Bengal.

Ctg Wasa officials said Sea level rise and decrease of water flow from upstream due to the impact of climate change, salt mixed tidal water enters Halda river. Moreover, Ctg Wasa held a meeting with the Bangladesh Power Development Board a few months ago to deal with the salinity problem. A letter has also been sent to BPDB to fix the flow of water in Kaptai Lake.

The chief engineer of Ctg Wasa said, "We check the salinity of water regularly. Whenever the salinity in river water is found to be high, we mix underground water before supply to residents. If we find excess salinity then the plant is shut down."

However, so far Mudnaghat-Pomra plant has not been affected by the rise of salinity in the water, said Engineer Maksud.