It blighted parts of Lancashire for more than a month and cost water bosses £25m.
But 14 weeks on from a microscopic bug being found in tap supplies, scientists are still not sure how it got there.
An investigation launched by the independent Drinking Water Inspectorate into the cryptosporidium contamination has so far failed to reach a conclusion.
And both United Utilities and Public Health England admit they are still in the dark about what caused one of the biggest health scares the county has ever seen.
“Our investigation is still ongoing,” said a DWI spokesperson. “At the moment we can’t say when a report will be ready.
“When it is it will be made available to the public in due course. We understand that it’s more than three months, but we can’t say any more.”
It was exactly 14 weeks ago this afternoon - August 6 - when more than 300,000 homes and businesses were first warned to boil all drinking water to protect against the nasty parasite.
Preston, South Ribble, Chorley and the Fylde Coast were affected and it took 30 days for all supplies to return to normal, leading to compensation payments of between £50 and £60 to all domestic consumers and much more to businesses affected by the alert. A dead pheasant in an outflow pipe was the most popular theory as to the source.
United Utilities insists it is still waiting to hear what the DWI has found, especially as the investigation has centred on its water treatment plant at Franklaw near Garstang.
“It’s out of our hands,” said a spokesman. “It’s a DWI investigation and we will get the results at the same time as everyone else.
“We have no control over it and we don’t get told anything. This is being done by independent Government inspectors and we are waiting for the result just like everyone else.”
Public Health England, whose role during the crisis was to monitor any health problems linked to the contamination, admits it too is playing a waiting game. “These processes usually do take quite a while, so the timescale isn’t too surprising,” said a spokesperson.
“But the DWI are the ones any questions should be directed at.”
For all our previous coverage on the water contamination situation in Lancashire visit the links below: