In addition to medium and long-term measures to address the smell coming from its south sewage treatment plant, the City of Castlegar has implemented some quick fixes.
Municipal services manager Chris Hallam updated city council this week after meeting with about 30 community members on May 23 to explain where foul odors have been coming from and what the city is doing to stop them.
Hallam explained spring is generally a bad time for treatment plant odor. As the temperature increases, biological activity kicks in the plant, contributing to the smell. Fats, oils, and greases that have settled in pipes over the winter begin to move. The plant doesn’t have a way of separating them out, so they end up in the biological reactor where they don’t break down well. When they do, the smell is the result.
Consultant Urban Systems reviewed the Castlegar plant in the Woodland Park neighbourhood and found that the main source of the smell was foaming in the bioreactor due to the influx of fats, oils, and greases. Additionally, some odor was coming from sludge basins.
Hallam said they have already taken some short-term actions including installing a sprinkler system to reduce foam buildup, pumping foam and grease and disposing of it offsite, and adding a digestive product to upstream lift stations to break downs fats and greases before they reach the plant.
They also plan to empty the sludge basins of biosolids, which needs to be done anyway in preparation for the medium-term solution of installing something called a Geotube de-watering system.
“We’re well on our way to implementing those short-term solutions and we’re pretty hopeful the cumulative effect is going to have a positive impact on odor reduction,” Hallam said. “Yes, while there are odors we are doing a lot down there and have committed a lot of effort and resources.”
In the long-term, Hallam said odors will be further addressed through a new liquid waste management plan that is now in the works, as well as bylaw updates to require grease separators, and bringing an idle biological reactor online.
Last month council approved $50,000 in consulting fees toward the Geotube system, which is expected to cost another $386,000 to supply and install. An inspection last year by Environment Canada found the city needed a better plan to manage liquid biosolids.
Hallam expected to have a report to council Aug. 14 to award the contract and figure out how to pay for it.
Councillor Shirley Falstead thanked Hallam for meeting with residents and councillor Cherryl MacLeod said Hallam “did an amazing job of allaying fears” and explaining plans to fix the problem.
“From the people I talked to afterward, they felt heard, like their concerns were valued and they had some faith the city was listening.”
However, councillor Sue Heaton-Sherstobitoff said she didn’t know about the meeting despite living in Woodland Park. Hallam explained it was organized by a resident, not the city, and therefore they didn’t control who was invited.