Sewage may save kokanee
The Daily Courier
Wednesday, May 1, 1996
KELOWNA — Flushing the toilet could save the kokanee.
The dramatic decline in the Okanagan Lake kokanee population in the last few years has rekindled memories of a unique experiment in the late 1980s when fingerlings were reared in the city’s sewage treatment plant.
“If we’re serious about wanting to get kokanee back into our lake, here’s a way to do it,” Mayor Jim Stuart told city council Mondays
He will write the Ministry of Environment asking for help in exploring what could be a low-cost solution to declining fish populations.
In 1984, the city joined forces with the ministry and Okanagan University College instructor Peter Dill to rear the fingerlings in treated sewage water.
The experiment was conducted mainly to prove that the city’s Bardenpho sewage treatment plant really was purifying the water it discharged into the lake.
“Because of the fish, we could prove 100 per cent that nothing was wrong with the water,” said Coun. Henry Markgraf, who worked on the project. “The water was cleaner than anything in the lake.”
The fish were tested for 70 elements and all were within acceptable limits, Markgraf said.
The project ran from 1984-89. In one year 10,000 trout were reared while an equal number of kokanee were reared another year.
In 1984, it only cost about $10,000 for fencing to keep birds out and other equipment to start the project in one of eight outflow chambers at the treatment plant. The program then cost about $10,000 a year to run.
Markgraf said the number of fish could be eight or 10 times what were reared in the 1980s, meaning up to 100,000 a year.
“For the students, it was a project of love,” Stuart said. “It was a pleasure to go down there to see it.”
It ended when funding from the provincial government stopped.
The city wanted to release the kokanee into Okanagan Lake but the Ministry of Environment refused.
“They felt tourists would look at it in a negative way because, technically they were raised in number two water,” Markgraf said.
Coun. Robert Hobson, chairman of the Okanagan Basin Water Board, explained that one of the reasons the kokanee have declined is because they can’t compete with fresh-water shrimp at an early age.
The idea, then, would be to rear the fingerlings until they’re old enough to feed on the shrimp.
“But,” he joked, “is there a possibility the fish would try to swim up the sewage pipe to spawn?”
Not likely. Stuart explained that the fish would likely be released in Mission Creek with the hope they would return there to spawn.