The next step of the city’s Liquid Waste Management Plan is set to commence following a tender award for the Coal Creek sanitary sewer project.
“This really is a big part of our stormwater and underground work in the coming years,” says city engineer Guy Cicon.
“Our effort here is to separate rainwater from our combined sewers.”
The tender for the project was awarded to the low bidder, Copcan Civil Ltd., for $115,379.
According to city engineering technician Boyd Wong, only approximately 40 per cent of the city’s sewer system is twinned out (separated) into sanitary and storm sewers—the rest is combined.
Most of the south side of town—where Coal Creek is located— is not twinned out because of the city’s history. Much of the city’s sewage system was constructed pre-amalgamation. At the time, the city of Port Alberni (now South Port) went with a combined sewer system. The city of Alberni (North Port) separated its systems.
Separating the combined sewers on the south side of town has been a decades-long project, Cicon said. “A big element of our liquid waste management plan is to separate out the rainwater that doesn’t need to be treated and pumped,” he said.
“Coal Creek is a catchment area we’ve been focusing on for a few years now.”
Coal Creek is located at Weaver Park and the segment of the work that was tendered runs under Third Avenue and requires work outside of city crews’ scope.
“There’s a huge fill there and to excavate this by conventional means would require a lot of excavation time,” said Cicon.
“Using directional drilling technology, we’re drilling into the embankment and pulling a pipe through which will act as our new sanitary sewer line.”
The current combined sewer line will continue to function as the city’s stormwater main.
Cicon said that hitting rock—as the city recently has during utility work on Third Avenue and Neill Street—isn’t a concern.
“We know that this area has been filled so the wild card here is are we going to hit any rubble that we can’t drill through?” Cicon said, adding that the contractor will pay for any extra costs.
The city has done some test holes in the area to get an idea of the composition of the fill and Cicon said it was possible to shift the drill over and avoid any rubble.
Work on the sewer separation project will start in the coming weeks and will take 60 days to complete.