The National Water Supply and Drainage Board (NWSDB) today assured that the drinking water in Colombo and the suburbs had not been contaminated with arsenic or any other toxic chemical despite public concerns to the contrary.
NWSDB General Manager B.W.R. Balasuriya said there had been public concerens about the quality of drinking water sourced from the Kelani River.
"Water from this river is treated at the Ambatale and Biyagama water treatment plants before being supplied to consumers in Colombo and its suburbs," he said.
Mr. Balasuriya said samples taken from the Kelani River were tested for arsenic every week at the laboratories in these two plants, and its content had not exceeded the permissible amount of 0.05 miligram for a litre of water.
He said the permissible level of arsenic in drinking water should not exceed 0.01 milligram a litre and that this level was never exceeded.
"Water treatment is carried out according to the required specification determined by Sri Lanka Standards 614-2013 and that the treatment plants in Ambatale and Biyagama had at all times complied with international standards -- ISO 9001-2008.