A rather unpleasant, embarrassing and disgusting phenomenon has been happening in British Columbia, Canada.

Imagine one day you are riding along in your car. It's a nice day and you have the roof open when all of sudden you are literally being showered in poo.

Like, actual human faeces...

This is exactly what has been happening to several people in the Canadian province in the past few months.

IFL Science reports that this first began on May 9, when Susan Allan and her son stopped at a red light in their car when it started to rain excrement.

Her green BMW was soon covered in a brown and grey liquid which reportedly smelt very bad.

She told local news site Castanet:

It stunk, it was gross, it felt dirty and right away you could smell poop. It was falling from the sky… you could feel the drops hitting you.

Susan and her son claimed that they saw a plane passing overhead at the time and a later inspection upon her eye revealed that she had conjunctivitis in both eyes from the sewage from the plane.

She also had a burn in her eye, which apparently came from the liquid chemical used from freezing water in planes.

Speaking after the event, Daniel Savoie from Transport Canada said that they were taking the incident very seriously.

You might be forgiven for thinking that this was just a freak occurrence but low and behold it has happened seventeen different times since in the skies above Canada.

Incidents range from a man noticing that his car on his drive had fallen foul to the poo, to a family 3,000 kilometres away in Yellowknife on June 24 being showered while sitting out on their deck.

No official explanations have been given but the most common theory relates to 'blue ice,' which is the chemical used to freeze human waste.

Aeroplane toilets cannot be emptied while in the air due to obvious health reasons but accidents such as seepage from the valves that open the tanks can occur.

A statement was given to CBC, from Transport Canada spokesperson Pierre Manoni said:

If this happens, the liquid seeping from valves freezes and adheres to the outside of the aircraft when the aircraft is flying at high altitudes As the aircraft starts its [descent] and the atmosphere gets warmer, the ice will start to melt and pieces will detach themselves from the aircraft. These pieces of ice will either melt or remain in their solid state before hitting the ground.

Yet in another twist, Transport Canada told Motherboard that the descriptions of the poo didn't match that of blue ice.

Upon review they said:

The department’s review has concluded that these incidents do not meet the description of blue ice and are therefore not aviation-related (i.e. the substance did not come from passing aircraft).

For Susan Allan, this explanation isn't sticking and she is now seeking help from a private investigator to potentially solve the matter as well as consulting flight patterns and speaking to other victims on social media.

She added:

I believe this is a cover-up by the government.

Another theory has come from Ross Aimer, a retired United Airlines captain and chief executive of Aero Consulting Experts told CBC that the excrement could be coming from Canadian geese.

Canadian geese, that we all know very well, have a migrating pattern where the scientists know exactly when and where they migrate. These birds could be literally hundreds of miles away when they poo and that could be carried onto, unfortunately, Linda's backyard. Especially when she said it was black. That could be bird excrements.

We hate to make a joke out of this but what can we say: 's**t happens'.