What is the ultimate capacity of Hudson’s sewage treatment facility?
According to the people who built it, 25% more than what it was originally designed to handle, with future expansions possible. I have been told the system is currently operating at approximately 60 per cent capacity, but the only confirmation I’d accept from this administration would be in the form of flowmeter data.
The 25% comes from former Hudson/St. Lazare Gazette reporter Matthew Brett’s sewer system notes from November 2007, which I post verbatim together with a big thanks to Matt for preserving them in digital form:
Whole system will be housed in a two-storey round building 28 metres in diameter according to town engineer Trail Grubert. Six-acre site off Wharf Road, next to the municipal snow dump.
Grubert said they’d looked at six other zones that weren’t suitable.
Space already belongs to town, so didn’t have to buy more property.
Discharge flows into the Lake of Two Mountains.
Denis Provencher of LBCD says it will use industrial processing tanks, called sequencing batch reactors (SBRs), to remove bacteria and solids from the water.
The first step in the treatment process involves what Provencher calls a “rotary screen,” where solids bigger than 6mm are filtered out. The liquid waste flows into an equalization tank to await transfer to one of the four SBRs. There, each load is pumped full of oxygen, which promotes the growth of aerobic bacteria that consume the particles found in the sewage.
Afterwards, the wastewater is left to settle before being separated from the leftover sludge. The water goes through a further ultraviolet disinfection process before flowing into the Lake of Two Mountains through a 300-metre pipe. The sludge is treated and dried, and periodically disposed of in a landfill.
According to Provencher, the water and sludge being returned into the environment must meet strict government requirements. One reason the town is installing the system is because municipalities downstream complained to the Ministry of Environment that Hudson is discharging raw sewage into the Lake of Two Mountains.
Building is equipped with a carbon filter that neutralizes odours.
Acoustic enclosure dampens noise.
For now, the sewer system will be available to businesses and residents in the town’s centre within the boundaries of Lakeview, Mount Pleasant, Côte St. Charles and Main Road, and all civic addresses on Bellevue, Sanderson, Seigneurie, Wilkinson and Parsons.
Provencher said the treatment facility has been designed to handle a larger service area in the future. “In the design, considerations have been given to future expansion. For example, by converting the equalization tank to a SBR, the capacity can be increased by 25 percent,” he said.