A contractor will be taken to task for polluting a canal in Bukit Timah with silt, the PUB said yesterday.

In its statement, Singapore's national water agency said it had investigated and confirmed that the material discharged into the canal after a heavy downpour last Wednesday was silt.

"We have traced the silty discharge to a nearby construction site that had failed to provide adequate earth control measures on site," the PUB added.

In a video provided to citizen journalism website Stomp last Wednesday, pale, muddy water can be seen flowing out of openings on the inner walls of the canal on what appears to be a rainy day.

Silty water is generated when rainwater run-off mixes with exposed earth materials and soil at construction sites, the PUB said.

The contractor has since rectified the lapses and the agency will be taking enforcement action against the company, the PUB added.

Contractors are required to implement measures at construction sites to remove silt from water before discharging it into public drains.

Offenders can be fined up to $5,000 for each offence of silty water discharge, and up to $50,000 for inadequate earth control measures.