Changes to construction projects eyed after spring sewage discharge

Hey there, time traveller!
This article was published 08/11/2022 (1082 days ago), so information in it may no longer be current.

New deadlines and fees for missing them could be applied to certain sewage-construction projects, as the city tries to prevent a major discharge from being repeated.

In a letter to the Manitoba government’s environmental compliance and enforcement branch, a Winnipeg water and waste official explains why 78.5 million litres of diluted sewage wound up in the Assiniboine River between March 16 and 25. Shortly after, city officials noted the construction-related pollution could have been prevented.

“It’s unfortunate. Had the project been completed by the March 11 timeframe, we wouldn’t have had to do any controlled discharge,” said Cynthia Wiebe while she served as acting director of water and waste last April.

In a letter the province posted online at the end of September, Wiebe (now manager of engineering services) lists several recommendations to reduce the risk of spills from similar projects in the future.

On a case-by-case basis, the city will consider the following steps for projects that require temporary sewage bypass pumping: tendering projects earlier in the year; charging construction companies a higher amount for damages when they fail to meet substantial performance dates; and deeming March 1 a “critical” in-service date for such contracts (which rely on frozen conditions to help reduce the risk of sewage spills).

A request to speak with a water and waste official was not granted Monday. In an email, spokeswoman Lisa Marquardson stated the city will aim to close tenders for this type of future winter riverbank project by late October and impose the March 1 construction completion deadline, “where possible.” She said the amount of potential “liquidated damages” that could be tied to construction deadlines would vary by project, while all changes would be applied “where appropriate.”

“For current and future riverbank projects, all the recommendations will be considered and implemented as appropriate,” Marquardson wrote.

In the March spill, last winter’s abnormally large volume of snow began to melt before a Portage Avenue interceptor sewer pipe replacement could be finished. That moisture combined with wastewater to exceed the capacity of the site’s temporary pumping system.

In the letter, Wiebe reveals that project was not awarded until Dec. 29, leaving the contractor little time to plan. On top of that issue, a city sewage gate failed and a water main break took place upstream of the construction area, increasing flows into the system. A specialty part also failed during installation, while cold, blizzard-like conditions slowed or stopped construction at multiple points of the project.

A large rainfall added to the flow on March 15, while the rapid melt of the large snowpack began on March 16, the letter notes.

“Both the primary and back-up bypass pumps were running at full capacity along with… mobile vacuum trucks. However, the high wet weather flows exceeded this combined pumping capacity and flooded the construction site. To manage site flooding, a controlled discharge was initiated later that same day to the Assiniboine River from the upstream pump station,” Wiebe notes.

The head of council’s water and waste committee said he’s hopeful the city can act quickly to ensure this type of spill is not repeated.

“That was an ugly spill that occurred,” said Coun. Brian Mayes.

Mayes noted improved sewage treatment is a council priority. The city has now secured funding to complete the first two phases of a three-phase $1.85-billion North End sewage treatment plant upgrade and has promised to increase municipal spending by $60 million between 2024 and 2027 for an up-to $2.3-billion plan to reduce combined sewer overflows.

Mayes expects the measures to prevent construction sewage spills should address one source of pollution long before those multi-year, mega projects wrap up.

“We should be able to better contain, better control, better penalize on something like this. Something like this seems like a more solvable problem,” he said.

The councillor warned the city must also ensure construction bids remain attractive enough to secure competitive bids and avoid significant cost hikes.

“At some point, ‘What’s the implication for your water bill?’ is a fair question,” he said.

A provincial response to the city’s letter states the Manitoba government has closed its file on the March sewage spill, which a spokesman confirmed in a written statement Monday.

“The province is (of) the opinion that (the) city will take appropriate pre-emptive steps for the prevention of reoccurrence in future projects. No further action will be taken at this time,” the statement said.

joyanne.pursaga@freepress.mb.ca

Twitter: @joyanne_pursaga