The source of a large diesel fuel spill in a northwest storm drainage pond was a fuel tank being used by a construction contractor, the city says.

As first reported by CTV News, the Ministry of Environment and Climate Change was called in after the Thursday spill.

Ward 7 councillor Josh Morgan says the contractor hired “a dedicated spills contractor” to clean up the fuel.

The work is being conducted under the direction of the MOECC.

He says the city’s spills team was immediately called after the spill. The ministry later released the city from the site. “However, we’ll remain on standby should the Ministry require further assistance,” Morgan says.

Neighbours in the area expressed concern about the spill, as wildlife are often found there.