Piping Perfection: PVC Pipe Project Improves Beachside Community’s Sewer and Storm Systems
The community of White Rock in British Columbia, Canada replaced its entire sewer and storm pipe system with new PVC pipe for its performance, durability and easy installation.
The seaside community of White Rock in British Columbia, Canada, is surrounded by the waters of the Semiahmoo Bay, and a vast majority of the properties are built on a hill. Given the heavy precipitation in the region, drainage is a cause of concern.
Since the community had built up gradually over time, the sewer and storm pipe system inevitably became a mix of different materials, including PVC, asbestos cement and concrete. "Basically it had gone through a lot of piecemeal upgrades," explained engineer David Chan, a branch manager with Aplin & Martin Consultants Ltd. in Surrey, BC, the consulting engineers for the replacement project.
|British Columbia's White Rock community replaced its entire sewer and storm pipe system with new PVC pipe.|
In 2012, the decision was made to replace the entire system with new PVC pipe. The $1 million project would entail the installation of over 1,800 meters of storm and sanitary sewer pipes, 34 manholes and 130 service connections.
The materials of choice included Royal SDR 35 Solid Pipe and SDR 35 Gasketed Sewer Fittings. "Since this was a complete end-to-end replacement, we used 250 and 300 mm pipe for total run of 850 meters," Chan explained. "For the most part, we were able to use the same alignment, with some sections slightly offset."
Installation began in early 2013. There were a number of unique aspects to the project, Chan noted. "The system was on a steep hill, and we came across a lot of unknown surfaces," he said. "The ground conditions were not the greatest, and in one section there was a layer of old road that we had to cut through. Royal provided a lot of support in determining the different sizing methods and materials we needed," he said.
He noted that PVC was the obvious choice because it is lightweight, durable and easy to install. "It gave us a lot of flexibility because two PVC pipes could be laid side-by-side. This twin trenching approach allowed installation to be done in a very quick and efficient manner."
This could not have been achieved as effectively with a thicker-walled pipe such as concrete, he explained. "The thinner walls meant the trench could be narrower, which was less disruptive to the community and would require less road cuts."
Another unique aspect of the project was the fact that the system was positioned in the middle of the hill. This required a number of pump connections for homes on the lower side of the hill, while the higher side was served by gravity. "We had to pay a lot of attention to ensure all the connections were tied in properly."
"Working on a hill with a lot of grade made for a very interesting job," said Dan Bubyn, project manager for Pedre Contractors Ltd. in Langley. "Having properties pumping into the mains from below is not all that common."
Given some of the underground surprises, design changes were needed as the project progressed. Adapting to the changes was made much easier with PVC pipe, Bubyn observed. "The pipe and fittings were easy to work with, so we could install a lot more lineal feet in a day compared to other types of products."
He adds that being able to combine both pipes into a single trench also reduced the workload considerably. "The ability to move things around when we needed allowed us to work in and around existing utilities in a safe manner."
Flexibility was critical for this project, Bubyn said. "When you're dealing with less than ideal ground conditions and an older infrastructure with different materials, you need to come up with answers quickly," he said. "You want to feel confident you can come up with the right solutions and provide good products to the owner when you're making those decisions. With PVC, changes can be made quickly, and it's easy to make it do what you need it to do," he explained.
Bubyn noted that in addition to a having a great product, the customer service provided by Royal and distributor Corix Water Products was outstanding. "We've had a great, long-standing relationship with both," he said. "The customer service has always been excellent, and they always ensure we have what we need. They make it easy for us to get the job done."