CHATTOGRAM, Mar 21: The supply of drinking water by the Chattogram WASA has declined from 50 million to 100 million litres per day (MLD) due to continuous high salinity of the Karnaphuli and Halda rivers.
The authorities said that the situation might improve only after sufficient rainfall. During the dry season, the people of Chattogram will have to suffer from this problem till the rainy season is come.
Chattogram WASA sources said, the present salinity level in WASA's water reached a record high of 2,320 mg per litre. But according to World Health Organisation, the allowed salinity for drinking water is 300 mg per litre.
Following the high salinity in the water of Karnaphuli and Halda two sources of water for WASA, the authorities are constraint to operate the production plants very carefully.
They are producing water during the low tide. During high tide production in all plants remained suspended.
Salinity in the water supplied by the Chattogram WASA has increased due to flow of saline water from sea to upstream of Karnaphuli River recently.
In some areas of the city, the water became unfit for consumption for drink.
Mohara Water Treatment Plant is supplying water after treatment of the fresh water of Halda River, situated 24 km upstream from the Bay of Bengal.
But the water of Halda River has turned into salinity recently due to low water current of the river Halda following for decrease of water release from the Kaptai dam.
According to WASA sources, since late December, salt levels have been detected in the Karnaphuli and Halda rivers, with concentrations rising steadily through January and February. Now, in March, the salinity has reached an unbearable level, creating major concerns for the city's residents.
Sources said that the salinity increased during the high tide. So during the low tide, the WASA plant go on production to avert high salinity of the water of Karnaphuli river and Halda.
WASA attributed the reasons of high salinity to drought and declining of releasing of water from Kaptai lake.
The sources said that the salinity of river water has increased to a higher level due to lower flow of water current for the release of negligible quantity of water from the Kaptai Lake as the water level at the Lake had declined alarmingly.
Sources said that the situation may continue till the rainy season. The Mohara plant can only purify the water from waste and bacteria but can not reduce the salinity level, sources added.
Presently, CWASA is producing 500 Million Litres per Day. But due to increase of salinity, the authorities have reduced the production at 50 to 100 million litres daily.
