Colombo Water Scare Ends With All-Clear, Questions Remain Over Mystery Blue Substance

COLOMBO (News 1st) - What began as an unusual sight in a paddy field in HeIyanthuduwa quickly escalated into an overnight emergency operation involving the National Water Supply and Drainage Board (NWSDB), Police, the Disaster Management Centre and environmental authorities, ultimately leading to the temporary suspension of water supply to parts of Colombo and its suburbs.

The National Water Supply and Drainage Board today (25) assured the public that water distributed through the Ambatale and Kelani South Bank Water Treatment Plants is safe for consumption, following extensive laboratory testing carried out after a suspected contamination incident near the Kelani River.

NWSDB Chairman Chandana Bandara said laboratory analyses had confirmed that water quality meets required safety standards and that normal distribution has now resumed.

The precautionary measures were triggered after residents in Heiyanthuduwa noticed something unusual yesterday (24) afternoon, when water flowing through a paddy field turned a striking blue colour.

Alarmed by the discovery, residents traced the path of the discoloured water and eventually found that it appeared to be flowing from a drain connected to a container yard owned by a private company.

One resident said the discovery immediately raised concerns that a chemical substance may have entered the water.

"We felt that something had mixed with the water, possibly a chemical. We followed the flow of the water for nearly one and a half kilometres and discovered it was coming from a container yard on Samurdhi Mawatha. We immediately informed Public Health Inspectors and the Police. The water eventually flows into the Kottunna Oya and then reaches the Kelani River through Raggahawatta," the resident said.

Another resident claimed they observed activity inside the premises after entering the property.

"When we entered through the gate, we saw soil being spread over the affected area, apparently to cover the leaked substance. We questioned what was happening and insisted the matter be properly investigated. We then contacted the Public Health Inspector and the Police arrived shortly afterwards. The water flows through the paddy fields into the Kottunna Oya and eventually reaches the Kelani River," the resident said.

The potential environmental implications attracted immediate attention given the location of key water treatment infrastructure downstream.

Geographical data shows the container yard is situated approximately 3.5 kilometres from the nearest point of the Kelani River. The Kelani South Bank Water Treatment Plant in Biyagama is located roughly 2.5 kilometres from the nearest river point adjacent to the yard, while the Ambatale Water Treatment Plant is approximately 3.5 kilometres away.

Representatives at the container yard told News 1st that a container carrying a solution used in the manufacture of rubber gloves had recently arrived at the premises.

According to them, a leak was detected before the container entered the yard, prompting workers to immediately move the vehicle inside and clean the empty container. They maintained that rainwater subsequently carried some of the liquid outside the premises.

However, when questioned by News 1st about the exact nature of the substance, the company representatives declined to disclose its identity.

Residents say concerns intensified because the Kelani River serves as a critical source of drinking water for a large population.

"Further downstream are the Pattivila Water Treatment Plant and the Ambatale Water Treatment Plant. We informed the authorities immediately. Once the information reached them, the plants were shut down as a precaution. Officials from the Water Board, Gampaha, Ambatale and Pattivila all arrived at the location," another resident said.

Amid fears that contaminants could have entered the river system, the Water Board suspended operations at both treatment plants at around 11.30 p.m. last night, disrupting water supply to Colombo and surrounding areas.

A large-scale emergency response was then launched.

Chairman Chandana Bandara said the Board moved swiftly to determine whether any harmful substances had entered the water supply.

"We immediately launched an urgent investigation into the incident. Officers visited the location and examined the alleged discharge of waste material. The Disaster Management Centre also became involved. From that moment until this morning, we continuously monitored water quality at various points along the Kelani River. Our laboratories were opened and samples were tested throughout the night. Once we confirmed that the water quality in the Kelani River was safe, we restarted both the Ambatale and Biyagama treatment plants at around 4.30 a.m. and resumed water production and distribution," he said.

Bandara also expressed regret for the inconvenience caused to consumers.

"We sincerely regret the disruption experienced by the public. This was a precautionary safety measure. At the time, we could not confirm whether any contaminant had entered the water source. Until that was established through testing, we had no choice but to temporarily halt operations at both treatment plants," he said.

When asked whether he could guarantee that contaminated water had not entered the distribution network, Bandara responded:

"We can provide that assurance."

Police said four complaints have so far been received regarding the incident, including complaints from members of the public and the National Water Supply and Drainage Board.

A joint investigation involving the Sri Lanka Police, the Central Environmental Authority and the Disaster Management Centre is now underway to determine exactly what entered the waterway, whether environmental laws were breached, and if further action is required.

While water supply has returned to normal and authorities have assured the public that the water is safe, the mystery surrounding the blue substance that triggered an overnight shutdown of two of the country's most important water treatment plants remains under investigation.