Bill Sims

City of Nanaimo fine tuning chlorine levels in drinking water

NANAIMO – City says noticeable chlorine in water due to higher filtration of particulate matter.

Operators at Nanaimo’s water treatment facility are fine tuning the water filtration system after a noticeable presence of chlorine in the city’s tap water.

According to a news release from the City of Nanaimo, the noticeable chlorine in the water is due to the increased filtration – previously, chlorine reacted differently with the higher volume of particulate matter in the water. Now the matter is filtered out, the chlorine is more evident.

According to the city, chlorine levels are down more than 25 per cent when compared to the previous disinfection system.

Regulations require chlorine level in drinking water to be within the range from 0.2 parts per million (ppm) to 4 ppm. The maximum amount that has entered Nanaimo’s system is 1.75 ppm, with the average being 1.3 ppm.

Additionally, chlorine – a disinfection agent used in municipal water systems across North America – may become more apparent in odour and taste as the temperature of the source water rises.

Through the month of August, an annual temperature increase in the city’s reservoir at Jump Lake caused water leaving the plant to carry a more noticeable presence of chlorine.

As water temperatures drop through the fall and winter, the presence of chlorine will become less apparent. As well, with the clearer water, the residual chlorine is extending further into the system.

After nearly 10 months of operation, the new water treatment plant is exceeding the city’s expectations in water quality filtration.

“We are very pleased with the performance and purity of water leaving the new water treatment plant,”said Bill Sims, manager of water resources. “While we’re happy with using less chlorine than in the past, we are working hard to dial the disinfection system in so that it’s less noticeable aesthetically. At this time of year, with higher water temperature, chlorine levels are less stable and therefore more noticeable.”

The city estimates it avoided six boil water advisories since the plant came online in December of 2015. Based on the turbidity of the water entering the plant at the South Forks Dam, operators can determine when the old method of filtration would have capped out the turbidity scale and triggered a warning. Sims said in an e-mail that several severe weather events last winter resulted in high stream flows that would have caused boil water alerts under Island Health’s new protocol had the new water treatment plant not been online.

Just Posted

LETTER TO THE EDITOR: City has an obligation as far as pedestrian safety

This is about ensuring the basic physical safety of our citizens, says letter writer

Theft of gas from Fairwinds golf course results in environmental damage

Approximately 400 litres seeped into nearby areas, including ponds

UPDATE: Deer that may have been hunted in area known for chronic wasting disease located

Conservation officers made urgent request for any info about hunters thought to be from Nanaimo

Nanaimo hospital foundation trying to Light the Trees to combat colon cancer

December campaign calls for donations to build new $1.5-million endoscopy suite at NRGH

Nanaimo Hornets to play first-ever quadruple-header

Hornets women and three men’s squads in action Saturday, Nov. 23, at Pioneer Park

Fashion Fridays: Holiday outfits on a budget

Kim XO, helps to keep you looking good on Fashion Fridays on the Black Press Media Network

Beefs & Bouquets, Nov. 21

To submit a beef or a bouquet to the Nanaimo News Bulletin, e-mail

City of Nanaimo budget talks underway, projected tax increase up to 5.6 per cent

Series of special finance and audit meetings was held Wednesday at conference centre

One person injured in rollover crash on Nanaimo Parkway

Accident happened a little after noon in southbound lanes near Cedar Road

Eagles congregate around Salish Sea for one last feast before period of famine

Mountainaire Avian Rescue Society preparing to receive birds in need of care

Canadian Forces member charged with possessing magic mushrooms in Comox

Master Cpl. Joshua Alexander, with the 407 Maritime Patrol Squadron, facing two drug related charges

Most B.C. residents, including those hit by 2018 storms, not prepared for outages: report

Create an emergency kit, BC Hydro says, and report all outages or downed lines

Study finds microplastics in all remote Arctic beluga whales tested

Lead author Rhiannon Moore says she wasn’t expecting to see so many microplastics so far north

Services needed in B.C. for early-onset Alzheimer’s disease patients: doctor, advocates

More patients are being diagnosed with Alzheimer’s at an earlier age

Most Read