Residents in the Canadian town of Onoway, Alberta got quite a shock on Monday night when their drinking water suddenly turned bright pink. And we're not talking just any old pink - that colour is outrageous.

Town officials have been forced to apologise to the locals, putting the neon nightmare down to a valve malfunction during some routine maintenance. Turns out, the pinkest chemical you've ever seen removes impurities from wastewater, and somehow it made its way into the Onoway reservoir.

"The Town of Onoway sincerely apologises for any alarm this may have caused. We assure you our water is safe and Public Works is doing everything they can to abate the situation as quickly as possible," the local council said in a press statement.

"During normal line flushing and filter backwashing, a valve seems to have stuck open allowing potassium permanganate to get into the sump reservoir. The reservoir was drained, however, some of the chemical still made it into the distribution system."

The chemical in question is a disinfecting agent known as potassium permanganate. When dissolved in water, it'll give you an intense pink or purple colour, and once this solution has evaporated, you'll have deep purple crystals.

Obviously, its ridiculous colour isn't why potassium permanganate is widely used in the water treatment industry - it's used to remove iron and hydrogen sulphide (rotten egg gas) from wells and wastewater.

The chemical can also be used as an antiseptic agent in wet dressings to treat superficial wounds, tropical ulcers, and lesions. 

The only real danger in using it is that it's a strong oxidiser - similar to chlorine - which means it can cause irritation or burns if the undiluted form makes direct contact with skin.

According to BBC News, no adverse effects were reported in this particular incident, and local officials have urged residents not to worry, because the pink water is perfectly safe to drink.

"The vast majority of individuals will not experience any impacts associated with normal consumption and no long-term health risks are associated with consuming this water," Alberta Health Services spokesperson Shannon Evans told the press.

The biggest issue seems to the fact that the locals were left to discover the horrifying pink-spolsion on their own this week - the town reportedly did not acknowledge the error until the morning after.

"We were never advised by Alberta Environment to issue a public advisory and all indications are that there was never a public health risk," Mayor Dale Krasnow said in a statement on Tuesday morning, according to CBC News.

"Could the town have done a better job of communicating what was going on yesterday to our community - absolutely, without a doubt. And we do apologise for that."

What apparently happened is that routine maintenance of the various water supply lines led to the malfunction of a valve that allowed potassium permanganate to get into the reservoir by mistake. 

Noticing the error, the water treatment staff drained the reservoir, but it was too late to catch the stuff that had already made it into the tap water system.

pink-water-2Erin Lacey/Facebook

"Yesterday, during normal line flushing and filter backwashing, a valve seems to have stuck open allowing potassium permanganate to get into the sump reservoir," the Town of Ottaway posted on its Facebook page on Tuesday morning (which has since been taken down, oddly enough).

"The reservoir was drained, however some of the chemical still made it into the distribution system."

"While it is alarming to see pink water coming from your taps, potassium permanganate is used in normal treatment processes to help remove iron and manganese, and residents were never at risk," the statement adds.

The tap water reportedly ran pink for a few minutes before turning clear again.

So there you have it. If you ever experience bright pink tap water, don't freak out - everything's probably fine.

Although it could be the return of the Ghostbusters River of Slime, so you might want to think twice before taking a swig.