Drinking water crisis plagues Ctg as salinity rises in WASA water

CHATTOGRAM, Mar 5: The supply water of Chattogram WASA has become undrinkable due to rise in salinity in the Karnaphuli and Halda rivers recently.

In some areas of the city, the water became totally unfit for drinking purpose.

Mohara Water Treatment Plant, situated 24km upstream of the Bay of Bengal and 1km upstream of the confluence of Halda and Karnaphuli rivers, supplies water after treatment, but water salinity has increased recently due to low water flow in the Halda River following persisting drought in the country.
The present salinity level of Karnaphuli River was recorded at 800 to 1000 mg per litre during the low tide, Engr AKM Fazlullah Managing Director of Chattogram WASA told the Daily Observer.

But according to World Health Organisation, the permissible level of salinity for drinking water is 300 mg per litre, he said.     
CWASA MD said the salinity increased during the low tide. So during the high tide, the WASA plant operates to avert high salinity of the water of Karnaphuli and Halda rivers.

He attributed to droughts and release of less water from Kaptai Lake for the high salinity in the river water.

Sources said the salinity of river water has increased due to less flow of water from the Kaptai Dam as the water level of the lake had declined alarmingly.

"We are drawing water from Halda and Karnaphuli during the ebb tide to avert salinity," Fazlullah added.

Sources said the situation may continue till the rainy season.  The Mohara plant can only purify the water of waste and bacteria but cannot reduce the salinity level, sources added.

Presently, CWASA is producing 500 million litres per day. But due to increase in salinity, the authorities have reduced the production to 20 million litres daily.

Sources said the Kaptai Hydroelectric Plant has been constraint to cut release of water drastically from the Kaptai Dam, making it unable to keep saltwater from entering the Halda and Karnaphuli rivers, which supplies water to Chattogram city.

All the plants of Chattogram WASA use water from Karnaphuli and Halda rivers.

Following the decrease in release of water from Kaptai Dam, saline water has moved upstream towards the entry points of WASA plants along Karnaphuli and Halda rivers.

According to Kaptai Hydro Power Station, they have been releasing a minimum quantity of water due to drastic fall of water level in Kaptai lake.

Several city areas, such as Halishahar, Uttar Kattali, Patenga, Baklia, Lalkhan Bazar, Shulkabahor, Amanbazar, Ambagan, Shershah, Kalurghat Industrial Area, and Chandanpura, are experiencing water supply disruptions.

Chattogram WASA has 78,542 residential customers and 7,767 commercial clients.

Meanwhile, Chattogram WASA has planned an ambitious US$400 million project to address the salinity issue, resulting from climate change, to ensure clean drinking water for the residents of the port city.

Officials said two international lending agencies - the Economic Development Cooperation Fund (EDCF) of Korea and the Japan International Cooperation Agency (JICA) - have shown interest in supporting and implementing the project.

According to Chattogram WASA sources, the port city experiences significant fresh water crisis during the summer. The escalating salinity levels in the water of this coastal city poses substantial challenges for the authorities in ensuring the production of clean drinking water.

Insufficient rainfall resulted in an increase in salinity in the Karnaphuli and Halda rivers, which are the major water sources for Chattogram WASA.