Tubers enjoying their journey down the Puntledge River last June. Photo by James Wood/98.9 The Goat/Vista Radio.
COURTENAY, B.C. – BC Hydro is giving migrating summer Chinook an extra push by doubling the flow of the Puntledge River, starting next month.
This is why people are being asked to use caution at different sections near the river’s edge.
According to spokesperson Stephen Watson, BC Hydro will soon begin its salmon migration flows to enable salmon to move up the five-kilometre stretch of the river, from the generating station to the Puntledge River diversion dam, and ultimately through a fish ladder at the Comox Dam and into the Comox Lake reservoir and beyond.
There will be five, two-day releases, starting June 11 and 12, and then taking place each Tuesday and Wednesday until July 10.
Every Tuesday and Wednesday from June 11 to July 10, BC Hydro will have a public safety caution advisory in place for the Barber’s Hole, Nymph Falls and Stotan Falls stretch as flows will be more than double the normal.
River flows at these location will go from about six cubic metres per second (6 m3/s) to about 12 m3/s 12 cubic metres per second, but can be as high as 17 cubic metres per second (17 m3/s).
Temporary safety signage will also be in place.
Water supply forecast
BC Hydro has released info on its water supply forecast that’s developed each year for the February to September period.
This considers precipitation and snowpack, as well as historical inflows over the same period.
The forecast provides a guide to BC Hydro operations in how they may need to conserve water supplies as into the summer and early fall.
Watson said “we have also been conserving water in the Comox Lake reservoir since February.”
The February to September forecast is updated each month, though the May updated forecast provides BC Hydro with the best reading of what the water abundance may be like this summer.
“That’s mainly because snowpack normally peaks around the end of April, as it did this year,” Watson said.
According to BC Hydro, the overall February to September forecast is for 61 percent of normal while the residual forecast (or the water supply from May to September) is 66 percent.
February and March were very dry. Precipitation for the month was 104 percent of average. May is off to a dry start at just three percent of average
BC Hydro has been running the 24 megawatt (MW) generating station at about 5 MW, or about 20 percent of capacity, for months to conserve water.
On April 25, they increased power generation to about 40 percent of capacity with the improving water conditions from snowmelt.
That means a water discharge downstream of the dam of about 20 cubic metres per second (m3/s), versus the typical release of about 32 cubic metres per second (m3/s) with the powerhouse normally running at full capacity at this time of year.
“We see the powerhouse operating at 40 to 70 percent of capacity into June,” Watson said.
Meanwhile, the the Comox Lake reservoir level is currently at about 134 metres, which is close to where it historically should be for this time of year.
A full reservoir is about 135.3 metres.
The range of reservoir operations is generally from 131 to 135.3 metres, and Watson said, “we plan to have the reservoir near full by June. BC Hydro will manage downstream flows as needed to manage the water storage through the summer for fish, domestic water supply and power generation.”