Squamish council has received a letter from the Queens Way lift station builder that says the facility was operating above its intended capacity before it failed.
At the same meeting where the letter came forward, elected officials were told the cost of restoring the station would exceed $1.7 million.
The District has hired Gravity Construction Inc. to do the job.
The station is still operating using temporary measures.
Recap of what happened
At the start of the year, the lift station at Queens Way underwent a catastrophic failure after a manhole collapsed. This forced officials to ask the public to cut down on their water use that day.
Ultimately, crews wound up expelling 1.59 million litres of wastewater into the Bridge Pond of the Squamish Estuary to prevent sewage from backing up into homes.
Crews were forced to install an emergency bypass to restore normal operations.
On March 7, two items related to that incident were on elected officials' agenda.
The letter was attached to the agenda. It outlined correspondence between Ueli Liechti, president of Duro Construction Ltd., and a municipal official.
What the letter said
In his letter, Liechti said his company built the lift station and the associated 300-millimetre — or 12-inch — forcemain to the wastewater treatment plant 25 years ago.
He said that at some point, a third party installed a 400-millimetre forcemain that terminated into the now-collapsed manhole.
"At the time, I voiced my serious concerns to the DOS [District of Squamish] engineer and his staff. This manhole was not designed for this large amount of volume and impact," wrote Liechti.
"The result of discounting my concerns has now become very clear."
He noted a 400-millimetre diameter pipe could pass almost twice the volume compared with the 300-millimetre outgoing pipe.
"The pump capacity has been reached and surpassed on and off for several years now as all four pumps are continuing cycling. The permanent emergency generator installed 25 years ago may not be able to handle the current power demand," he wrote.
Among other things, he noted the problem is that too many lift stations wind up feeding either directly or indirectly to the Queens Way station. He said the Valleycliffe Scott Crescent lift station pumps into the Cleveland Avenue system, which winds up at the Queens Way Station.
The same happens with respect to the Finch Drive Station pumping into the Industrial Way line, which also ends up at Queens Way, he said.
The solution, he said, is to install a forcemain via Loggers Lane directly to the wastewater treatment plant. The idea would be to redirect the Scott Crescent station's flow into Finch Drive pump station and then to the wastewater treatment plant, rather than burdening the Queens Way station.
This would free up capacity at Queens Way, he said.
Response from the District
Sarah Baillie, director of engineering at the municipality, responded to Liechti's concerns.
"The instances you speak of where the station ran all four pumps was due to sediment build-up in our forcemain, an issue that was identified in our Sanitary Master Plan," wrote Baillie.
"We recently cleaned the forcemain from Queens Way Lift Station to the wastewater treatment plant and have confirmed we have adequate capacity for current and near-term flows. The Sanitary Master Plan recommends that we upsize the forcemain at some point to meet 2050 flows and so we are monitoring the impacts of upstream development to ensure we implement the necessary upgrades at the correct time."
She also thanked him for his thoughts on potential solutions.
"The Finch Drive station actually pumps north up Loggers Lane as you suggest," she said.
"We also completed a study in 2012 of the viability of installing a forcemain from Scott Crescent to Finch Drive and decided not to pursue this option due to higher costs and the complexity of crossing Finch Creek."
In a follow-up email to The Squamish Chief after the meeting, District spokesperson Rachel Boguski said that staff appreciate Liechti's historical knowledge and insights from having worked with our sanitary system.
"District public works and engineering staff are focusing their efforts on the design and construction of the replacement manhole as it is still considered to be an emergency repair," she said, adding that confirming Liechti’s claims will require further time and investigation. "It’s also worth noting that groundwater conditions change seasonally, and what may have been the case 20-plus years ago may now be different. It’s also not known what shoring and dewatering techniques were used at that time and how they may differ from what is being planned as part of this work. We anticipate learning more as deep excavation work progresses," she said.
"The Lift station at Finch Drive and Loggers Lane pumps to a manhole at the intersection of Centennial Way and Loggers Lane. Wastewater then flows via gravity to the Brennan Park Lift station. The Brennan Park Lift Station pumps directly into the influent channels at the Wastewater Treatment Plant."
Questions raised by council
In a separate part of the March 7 meeting, District staff also briefed council on the situation, outlining what happened on the day of the failure.
Among other things, council raised questions about the budgeting for upgrading the station. Queens Way had been identified for some time as a problem station that needed work. Money had been budgeted for the work, yet it had not been done when it reached an emergency situation in January.
"We had put this to tender and 2021, 2022, and then here we are in 2023," said Stoner. "As I went back to those budgets, the line item for that project budget was $1.4 [million] in 2021, and then 1.4, again in 2022, and then 1.4, again in 2023. So I'm curious why we didn't escalate the estimate of that project cost if the tenders were not coming in within the original estimate."
Ben Kineshanko, the District's public works technical operations manager, said the second year the project was tendered, the budget was kept the same, but the scope was reduced.
However, despite this, all the prices were still well over budget, he said.
Stoner noted the budget for the wastewater treatment fund hasn't increased in a few years.
"If I go back and read the budget from 2021, it says 2% of the Master Plan suggests 2% of capital should be going into repair and maintenance, which, to me, reading it now, seems really low," she said.
Baillie said the rates were guided by a study done in 2018.
The sanitary master plan is due to be updated next year, and it will have updated numbers for these projects, she said.
"The rate study will again be done to help guide us on that budget increase," said Baillie. "So if the rate study is showing that they're recommending an increase, we'll bring that back to council for endorsement at that time."
Coun. Chris Pettingill wondered if the rate study process should be changed if those numbers are differing greatly from the present reality.
"If … we're going to start seeing periods of sudden significant escalation and so on, does that suggest we should adapt our processes?" he said.
Baillie said that the idea is to avoid being too reactive.
"Obviously, in the past number of years, COVID has had a large impact," she said. "But there are other factors that do happen over the course of construction that can also change pricing — various examples of certain supply chain shortages unrelated to COVID. So we don't want to be too reactive in how we approach this and bring forward, you know, constant rate studies."
Baillie noted, however, that the District was likely due for an update.
How were costs calculated?
Mayor Armand Hurford wondered how staff calculated costs for the work on the Queens Way station.
Baillie said staff collaborated with the contractor on this matter.
She said contractors brought forth estimates and staff reviewed them based on their experience.
"They were ultimately in the driving seat because of the nature of the emergency to let us know what the cost would be," she said. "To that note, we still don't have all the costs. We don't have all the costs of the day tabulated yet to bring to you."
She said the expenses would increase when factoring in the emergency work related to the incident.
"What you haven't seen yet is the cost of the [vacuum] trucks, the consultants we had on board that day, the excavator, so there's still a piece of that puzzle that we're not ready yet to present and still more costs, I expect, on top of that $1.7 million pricing."
