Water has been restored but residents could see fluctuations in pressure after a massive water main break in Kitchener.

The Region of Waterloo says in a press release that they have augmented the water supply to bring water pressures back after Wednesday morning's break.

Grand River Hospital had its water affected in the break, but water has since been restored to their services. A spokesperson for the hospital says that plans are in place to work later in the day to avoid postponing surgeries.

The large water main on Charles Street was hit by a contractor around 7:20 a.m. in the area of Madison and Cameron.

According to the region, the contractor was working for a private development on the block.

Drewlo Holdings says one of its contractors was drilling near the place of the break, but that the cause of the break is still unknown.

"A shoring contractor was drilling in a location near the break. All necessary approvals and locate requests were in place," the company says in a press release.

As of 11:17 a.m., King Street East had reopened to traffic.

The city is asking people avoid this area while repair work is ongoing, as a huge pond had formed in the area.

Waterloo Regional Police Service have closed a large section of the downtown area because of it.

The watermain break knocked out water service to a large portion of Kitchener and Waterloo.

Residents can expect fluctuations in their water pressure and discolouration of water, which can stain laundry.

It's recommended to run the cold water tap nearest to your water supply for ten minutes to get rid of discoloured water.

The region says not to drink discoloured water.