At the beginning of February, we had an interesting yet challenging project of waterproofing a manhole located at someone’s property on Tidemore Ave. in Toronto. This maintenance chamber was surrounded with soil oversaturated with ground water which caused it to always be full of water, in danger of over exceeding its capacity.
Repair Method
To be able to waterproof the manhole from the inside (walls and floor), all the water had to be pumped out first. Then the concrete surface was repaired by following our established methods: chipping was done to prepare the surface to be primed before black cement was applied to stop any leaking. Then a quick curing cement and parging mix were used. The surface was dried with torches and a waterproofing coating was installed.
Challenges and Solutions
Since the ground water could no longer penetrate the manhole, its level went up, and it started leaking from above. To eliminate this issue, a trench was dug around the manhole, and weeping tile was installed, which redirected the excess water into a nearby ditch. Digging the soil in -20°C weather was impossible, though, and this challenge was overcome by using a chipping gun to remove the soil (which was put back in after the weeping tile had been installed).
Learn more about our waterproofing solutions for manholes by visiting this page: https://www.jointsealwaterproofing.com/manholes
