Some untreated sewage leaked into Masset Harbour last Tuesday and Wednesday when a pump station east of the causeway lost power.
Sylvan Daugert, Masset’s superintendent of public works, says roughly 30 cubic metres of liquid sewage leaked before BC Hydro crews got the power restored.
The sewage plant that serves both Old Massett and Masset handles about 400 cubic metres a day.
“I don’t want to sound like I’m dismissing environmental concerns, but on the scale of the water that flows through Delkatla Slough and into Masset Sound, it’s literally a drop in the bucket,” said Daugert, noting that the sewage that leaked was mostly water, not heavy or floating solids.
“It’s quite a bit less of a concern than say one of of the diesel spills, because it’s purely a matter of dilution.”
At 9:29 p.m. Tuesday, a transformer by the causeway blew, cutting power to the lift station that pumps sewage from the Delkatla neighbourhood over the causeway toward the treatment plant in Old Massett.
That’s when Daugert and other village staff got an alarm that the station was backing up.
Daugert notified BC Hydro, the B.C. Ministry of Environment, and also called an electrician to look at the lift station pumps, which might have been damaged in the power surge, but checked out okay.
“That would have been a huge nightmare,” he said.
It was also lucky that neither of the fish plants were running, so sewage volumes were fairly low.
Daugert said the pumps at the causeway station have lost power or simply failed before, but normally the repairs are fairly quick, and finished before sewage levels reach the overflow pipe that enters Masset Harbour just south of the causeway.
The trouble last Tuesday night was that first BC Hydro needed a bucket truck from the south end, and then the crew found they had to rewire and replace a whole bank of transformers rather than swapping out a single one.
In total, the lift station was without power for 16 hours.
Until a shared plant with secondary treatment was built in 2007, untreated sewage from Masset and Old Massett was pumped into Masset Sound. Secondary treatment involves removing suspended solids, and also treating biodegradable organic matter.
In 2009, Queen Charlotte was fined by Environment Canada for decades of discharging sewage into Skidegate Inlet with only preliminary treatment — the village did receive permits for a secondary treatment plant in the 1980s, but it was never built. Sewage from the village is screened, ground into a slurry, and pumped 1.2 km to a deep-water outflow that is about 20 metres under the surface of Skidegate Inlet at low tide.
A study done in 2010 found the Village of Queen Charlotte had five options, including pumping its sewage east to the plant in Skidegate, which has an outflow in Hecate Strait about 50 metres deep. Councillors at the time preferred that option, though it was also the costliest, estimated at $10 million.
Queen Charlotte Mayor Greg Martin said it’s a major undertaking, and the next step will require public input. Councillors plan to make a final decision on the treatment question within the next two years.