MONTREAL -- The City of Montreal will be spending much of this winter repairing a massive pipe that distributes water to more than a million people.

Workers are travelling down almost 10 metres below ground to apply reinforcements to the structure, piece by piece.

“People are putting in place some layers of carbon fibres, so they glue it with Epoxy and they go all around the pipe, so it makes it very structural,” explained engineer Romain Bonifay.

The hope is to fix a portion of the two-metre wide water main after inspectors discovered last spring that it was in bad shape.

The pipe was closed off and city officials awarded an urgent contract to get the work done.

“We couldn't take the risk to leave this water pipe with water in it,” Bonifay said.

But, how does the water actually get all the way up to the taps in our homes?

It all starts at a treatment facility in Montreal’s LaSalle borough, where water is scooped up from the Saint Lawrence River.

It undergoes a filtration process before travelling down the pipe to the McTavish reservoir on Mount Royal.

Built in 1854, the reservoir holds enough water to fill 40 Olympic-size swimming pools.

 “We're producing close to one million cubic metres of water every day,” said Philippe Sabourin, spokesperson for the City of Montreal. “We're bringing water to 1.2 million citizens.”

While repairs take place, smaller pipes are being used in a carefully-calculated effort to keep the H2O flowing.

“People in the pipe [are] applying [materials] from the top to the bottom, they cannot step on it,” Bonifay explained. “They have to respect the time for drying…all the overlap. It's pretty hard work.”

As work continues into the winter months, some parts of the pipe will need to be replaced entirely.

The work is expected to wrap up in time for summer.