Okanagan Lake may not necessarily be the answer to Greater Vernon’s water demands.
Members of the master water plan stakeholders advisory committee were told Thursday that costly treatment processes will still be needed if the Okanagan Lake source is tapped.
“It will not likely be just chlorination and ultraviolet. There will be treatment,” said Dale McTaggart, Regional District of North Okanagan’s general manager of engineering.
While communities in the central and southern parts of the valley use Okanagan Lake for water, McTaggart says there are no scientific studies on water quality in the northern arm.
One possibility from using Okanagan Lake is trihalomethanes, a group of compounds that can form when the chlorine used to disinfect drinking water reacts with naturally occurring organic matter (decaying leaves and vegetation), according to Health Canada.
To avoid such situations, Zee Marcolin, Greater Vernon Water manager, says water pipes would have to be extended far out into the lake’s main arm and such a proposition could be expensive for the utility.
The other issue is that GVW is running into challenges getting provincial approval to access water from Okanagan Lake.
“It’s been a year-and-a-half and they haven’t even come to the table provincially,” said Marcolin of trying to obtain a water license.
“We’re in a holding pattern.”
One possible reason for the hold-up is that Greater Vernon may not need Okanagan Lake water for 50 years.
“It’s a low priority for them (province) because it’s not something you need right now,” said Rod MacLean, with Associated Engineering.
It was also suggested that provincial departments are short-staffed and facing demands from communities with immediate water issues.
While there have been suggestions of abandoning Duteau Creek for domestic use, Marcolin says it could still be needed if quagga and zebra mussels show up in Kalamalka and Okanagan lakes.
“With Kal Lake, the risk is high because of very high calcium levels. It’s the perfect environment (for the invasive species),” she said, adding that Duteau Creek has low calcium levels so its risk is reduced.
These mussels clog water intake pipes, pumps and boat motors. They also deplete food sources for fish and produce toxins that kill fish and birds and contaminate drinking water.