ENGINE oil that spilled into the River Cole from a drain is being contained and cleaned up by the Environment Agency.
A thick oily sheen coated the entire 3m width of the river for 3km downstream from the Walcot East area of Swindon.
After being alerted to the spillage on Sunday, the Environment Agency worked throughout the week to clean the river, stop any more oil escaping from the drain and investigate the extent of the damage to local fish and fauna.
The source of the slick is thought to be a surface water drain that serves a large industrial and residential area of Swindon.
The drain is owned and maintained by Thames Water, which is assisting with the investigation and containment by sending an oil spill contractor to the site to take over clean-up duties.
Environment management team leader Steve Wilkes was grateful to the observant citizens who reported the spill to them.
He said: “Thanks to members of the public quickly reporting the incident to us, and a quick response from ourselves and Thames Water to contain it, the impact has been significantly reduced.
“So far, we have found no dead fish but we have found evidence that invertebrates and other fauna have been quite badly affected and this will have knock-on impacts for fish and other species that feed on them.
“We are grateful to the members of the public who reported this incident to us and who therefore played a significant role in stopping it being far worse.”
Absorbent booms and pads were placed into the river to soak up the oil and clean-up work is continuing.
It is not yet known who was responsible for the mess, whether it was intentional or accidental, or how and where it got into the drainage system.
The agency has not yet established whether any environmental offences have been committed.
On Tuesday, the Environment Agency carried out ecological surveys of the river to assess the environmental impact of the oil spill.
The results will be revealed in a few days.
Oil is no longer entering the river but there is still a significant amount in the river, which is being cleaned up as quickly and safely as possible.
Mr Wilkes added: “We won’t hesitate to take firm action on those responsible for major pollution.”
“If anyone sees what they suspect may be a pollution incident, we would urge them to report it to us on our incident hotline 0800 807060.”