Greater Nanaimo Pollution Control Centre. (Photo courtesy Regional District of Nanaimo/Multivista)

Greater Nanaimo Pollution Control Centre. (Photo courtesy Regional District of Nanaimo/Multivista)

Greater Nanaimo Pollution Control Centre upgrades resulting in better water samples

$82-million project to add secondary wastewater treatment was completed earlier this year

An $82-million upgrade at the Greater Nanaimo Pollution Control Centre is greatly improving quality of water being discharged, says Regional District of Nanaimo staff.

The RDN announced in April that the secondary wastewater treatment project at the north Nanaimo facility was complete, utilizing technology that extracts solids during treatment. In a RDN liquid waste management plan monitoring committee presentation Thursday, Ryan Powell, RDN wastewater services’ senior lab technician, said effluent being discharged is less harmful to the environment.

Powell said carbonaceous biochemical oxygen demand is a measure of the oxygen demand of a sample. A sample with high oxygen demand can lead to depletion of oxygen in water, he said. Current provincial regulations are 130 milligrams/litre daily and federally, 140mg/L for monthly average, however, new regulations take effect in the next year for 45mg/L daily provincially and a 25mg/L monthly average federally.

“Commissioning began in September 2020 and there was a huge decrease in our CBOD,” Powell told the committee. “A month prior to commissioning beginning, our CBOD was 100mg/L. The month the commissioning began … that dropped to 68 and then in October, it dropped to 4.6. Incredible reduction.”

Powell also referenced total suspended solids found in water, a measure of particles which are unable to be filtered through a 1.5-micron filter. High levels of total suspended solids can be detrimental to the park ecosystem and clog fish scales and affect fish eggs.

“Prior to secondary [treatment], we saw 68mg/L, that dropped to 46 in the first month and then dropped all the way down to eight in the second month … we see the same nice drastic decrease that we’re seeing with [CBOD] and that decrease has been very stable since the commissioning occurred,” said Powell.

Ammonia levels are also tracked. Powell said un-ionized ammonia are the most detrimental form of nitrogen to fish and aquatic ecosystems. Samples are sent for testing using rainbow trout and various concentration samples for 96 hours. If more than 50 per cent of trout die, in samples with 100 per cent concentration, the effluent is considered “acutely lethal.” Before secondary treatment, there was an average of 41mg/L, Powell said.

“The secondary treatment plant is able to remove ammonia using [a nutrient removal process],” he said. “In 2021, we’ve seen really great ammonia removal ranging from 37 per cent in the winter months. You can’t get as much [removal] in the winter months because the temperature is lower, so the bacteria are less active … by the end of April, we were seeing numbers closer to 60-61 per cent and even higher in the last week.”

Last month, the average was 19.7mg/L, he said, and two toxicity tests saw all the fish surviving testing at 100 per cent concentration.

Don Bonner, RDN director and committee chairperson, told the News Bulletin he was pleased with the secondary treatment results and while it isn’t being considered yet, tertiary treatment would be the next step.

“Right now the water is well [within] the provincial standards, however, tertiary treatment frees us up for a lot more options in terms of recycling and reusing the water, that would be our next step going forward,” said Bonner. “It’s fairly expensive. To get the last 10 per cent [effluent in water] out is quite expensive.”

RELATED: Nanaimo’s $82M pollution control upgrade complete

RELATED: RDN finalizes financing for next phase of $80M pollution control upgrade

Like us on Facebook and follow Karl on Twitter and Instagram

Nanaimo Regional DistrictWastewater treatment

Just Posted

The 14th annual Oak Bay Young Exceptional Star (YES) awards June 3. (Christine van Reeuwyk/News Staff)
Oak Bay celebrates its Young Exceptional Stars with outdoor award ceremony

Nine young people recognized in 14th annual awards

A pub patio in Victoria. (Black Press Media file photo)
Patio and picnic dining could mean a free meal for Greater Victoria patrons

Local celebrities pick up the tab with latest Greater Victoria chamber contest

Greater Victoria School District (SD61) Saturday announced a COVID-19 exposure at Oak Bay High School. (Black Press Media File).
Oak Bay High School subject of COVID-19 exposure

Greater Victoria School District (SD61) said possible exposure happened June 9-10

St. Andrew’s Roman Catholic Cathedral in Victoria. (Black Press Media file photo)
Victoria bishop apologizes for church’s role in residential schools

Bishop Gary Gordon voices commitment to healing and reconciliation

Canadian Prime Minister Justin Trudeau participates in a plenary session at the G7 Summit in Carbis Bay, England on Friday June 11, 2021. THE CANADIAN PRESS/Adrian Wyld
Canada donating 13M surplus COVID-19 vaccine doses to poor countries

Trudeau says the government will pay for 87 million shots to be distributed to poor countries

Indigenous Services Minister Marc Miller is seen during a news conference, Wednesday May 19, 2021 in Ottawa. THE CANADIAN PRESS/Adrian Wyld
Indigenous child-welfare battle heads to court despite calls for Ottawa to drop cases

Feds are poised to argue against two Canadian Human Rights Tribunal rulings

The Great Ogopogo Bathtub Race has been held in Summerland as a fundraising event. Do you know which Canadian city introduced this sport? (Black Press file photo)
QUIZ: A summer’s day at the water

How much do you know about boats, lakes and water?

Two-year-old Ivy McLeod laughs while playing with Lucky the puppy outside their Chilliwack home on Thursday, June 10, 2021. (Jenna Hauck/ Chilliwack Progress)
VIDEO: B.C. family finds ‘perfect’ puppy with limb difference for 2-year-old Ivy

Ivy has special bond with Lucky the puppy who was also born with limb difference

A million-dollar ticket was sold to an individual in Vernon from the Lotto Max draw Friday, June 11, 2021. (Photo courtesy of BCLC)
Lottery ticket worth $1 million sold in Vernon

One lucky individual holds one of 20 tickets worth $1 million from Friday’s Lotto Max draw

“65 years, I’ve carried the stories in my mind and live it every day,” says Jack Kruger. (Athena Bonneau)
‘Maybe this time they will listen’: Survivor shares stories from B.C. residential school

Jack Kruger, living in Syilx territory, wasn’t surprised by news of 215 children’s remains found on the grounds of the former Kamloops Indian Residential School

A logging truck carries its load down the Elaho Valley near in Squamish, B.C. in this file photo. THE CANADIAN PRESS/Chuck Stoody
Squamish Nation calls for old-growth logging moratorium in its territory

The nation says 44% of old-growth forests in its 6,900-square kilometre territory are protected while the rest remain at risk

Flowers and cards are left at a makeshift memorial at a monument outside the former Kamloops Indian Residential School to honour the 215 children whose remains are believed to have been discovered buried near the city in Kamloops, B.C., on Monday, May 31, 2021. THE CANADIAN PRESS/Darryl Dyck
‘Pick a Sunday:’ Indigenous leaders ask Catholics to stay home, push for apology

Indigenous leaders are calling on Catholics to stand in solidarity with residential school survivors by not attending church services

Most Read