West London residents have slammed the authorities responsible for the city's waterways after a "mini ecological disaster" involving an oil spill in a canal took over a week to be resolved.

Southall residents living on houseboats at Willow Wren Wharf found their peaceful Sunday morning interrupted when they discovered a thick black film had surrounded many moored vessels on August 27.

Although the source of the leak has not been confirmed residents say that they saw engine oil escaping from "three waste-oil containers" which they claim spilled the pollution into the canal from upriver of the wharf.

The initial incident was reported to the Canal and River Trust on August 27 with residents saying that the last remnants of the oil were only removed this week.

This has prompted people like Andrew Bailes to speak out about the incident, one that he says was poorly handled by authorities. Writing in a blog on Narrowboatworld, Andrew expressed his frustration at the seemingly slow response by those responsible for the clean up as well as the lack of communication from relevant authorities.

He wrote on September 5: "From the Sunday that we reported the spill happened we didn't have anyone trying to pump the oil out of the water, I don't know if they have even tried yet. It was only a week later that [they] arrived actually prepared on site to do…something." Andrew says the response by clean up crews was not only slow but ineffective, adding that he could only see clear water around his boat because the oil "had sunk", not because it had been removed.

Andrew's wife Hannah said there have been two major impacts of the oil spill. Firstly she claims the oil has caused damage to the coating of boats in the wharf which costs about £2,000 to repair, and secondly the spill has had a serious impact on wildlife.

Hannah says she was particularly upset as residents watched helplessly as birds became disoriented after becoming coated in oil. "On Thursday morning I saw a coot bird walking along just covered in oil. It was just wandering around in a circle, it didn't know what to do.

"We didn't see what happened to it, that really upset me. I'm worried about the wildlife, the birds and the fish." Hannah and Andrew said that the whole debacle had been "depressing" to witness as they felt powerless to stop it.

"They should have acted faster, definitely, and taken it a bit more seriously," Hannah added.

Everyone who spoke to the Local Democracy Reporting Service (LDRS) said that someone was sent to assess the situation hours after the complaint was made on Sunday, August 27 and there were contractors coming in and out of the wharf but there appeared to be a lack of decisive and effective action.

Oil slick at Willow Wren Wharf (image by Rory Bennett)

One concerned resident said she had never seen anything like the spill in the almost 25 years she has been moored up in the wharf, adding that longstanding wildlife habitats had been disrupted by the pollution. Another resident confirmed that the oil had finally dissipated either through clean up efforts or the oil sinking by Wednesday this week.

Andrew says he doesn't believe the Canal and River Trust, the charity that manages waterways in England, had a coordinated clean up effort when responding to the incident saying employees "embarrassedly arrive" to throw down a line of oil absorbent buoys at one point that seemed to be the extent of the trust's response.

"It really angered me not to be taken seriously," Andrew said, adding: "All the environmental stuff has had an emotional effect as well and the feeling of powerlessness to do anything about it."

The source of the oil remains unclear, however, Thames Water confirmed that the spillage came from a third party. A Thames Water spokesperson said: "We were made aware of an oil spill in the Grand Union Canal between Hayes and Southall on Sunday 27 August.

"Our environmental and pollution teams investigated straight away and traced the pollution to a third party that operates upstream of our outfall. Taking action to improve the health of rivers is a key focus for us and we'd like to thank those for alerting us to the oil spill which we will be investigating further."

The Canal and River Trust has been contacted for comment while the Environment Agency said the waterway was the trust's responsibility.

It is an offence to cause or knowingly permit a water pollution discharge with sentences upon conviction ranging up to five years imprisonment. Thames Water has confirmed that due to the leak resulting from the action of a third party, it will not be offering compensation to those affected. The investigation into the source of the calamity is ongoing.