BC Hydro Puntledge River operations - high flows due to snowmelt
May 29, 2017
From Stephen Watson, Stakeholder Engagement Advisor at BC Hydro:
"With the abundance of water this year we would like to provide an update of our forecasted operations for the end of May and the month of June. With the recent warm weather the snowmelt off the local mountains has significantly increased. Beginning tonight, people are advised to not enter the Puntledge River given the higher water abundance conditions and planned water releases.
13th Annual Puntledge River Paddle Festival May 27-28
The event went well according to organisers with people coming from as far as Prince George. About 120 kayakers participated and there was also group river rafting. Even with the high targeted river flows during the day for the kayakers, the Comox Lake reservoir level finished the weekend roughly where it started on Friday evening.
Water releases from the Comox dam during the event ranged from 65 m3/s to 120 m3/s, with releases of about 45 m3/s at night. Despite the high kayak flow rates, the rate of the snowmelt and the water flowing into the reservoir kept the reservoir level unchanged throughout the weekend.
Water inflows into Comox Lake reservoir
Our hydrologists are forecasting a daily average of about 70-75 m3/s of water flowing into the reservoir today and tomorrow and then dropping down to about 50 m3/s by the end of the week.
For our water supply year for the Puntledge River system that goes from October 2016 to September 2017, and we are currently tracking at the second highest water inflow year in the last 49 years of record. The record setting water inflows from the storms in October and November significantly influenced this year’s water totals.
The reservoir is currently at about 135 metres, with 135.33 metres being full and beginning to free-spill over the spillway section of the dam. Our goal is to keep the reservoir from going above 135.33 metres
Water release from Comox dam
We are currently releasing about 32 m3/s from Comox dam, which is our typical release for power generation at full capacity and for downstream fish habitat flows.
BC Hydro will begin to increase Puntledge River flows starting at 9 pm today and have the flows at about 50 m3/s by Tuesday morning. The higher flow rate will last through to early next week when we re-evaluate the water abundance conditions.
Water release for Chinook smolts in coordination with DFO
With the cooler spring the Chinook smolts were not ready to be released during the annual kayak festival last week. In discussions with Fisheries and Oceans Canada (DFO), and with the water abundance this year, BC Hydro will release higher volumes of water down the Puntledge River on June 10 and 11 to give Chinook hatchery smolts, released by DFO, a better success rate in migrating past seals in the lower river out to the ocean.
Water releases from the Comox dam may exceed 55 m3/s.
Summer fish migration flows for summer-run Chinook.
This is the time of year for the summer Chinook salmon migration flows to enable them to move up the 5 kilometre stretch of the Puntledge River from the generating station to the Puntledge River diversion dam, and ultimately into the Comox Lake reservoir. There will be five, two-day releases, starting June 13 and 14 and then taking place each Tuesday and Wednesday until July 12.
From June 13 through to July 12, on each Tuesday and Wednesday, a public safety caution advisory is in place for the Barber’s Hole, Nymph Falls and Stotan Falls stretch of the river as flows will be more than double the normal. BC Hydro will reduce power generation on these fish migration flow days so the rest of the river system will not have safety signage. Power generation is reduced so fish can be more attracted to upstream river flows rather than the powerhouse water discharge.
Beginning tonight, BC Hydro advises the public to stay away from the Puntledge River system through to early next week, around June 6. Danger signs will be posted along the river by this evening. It is likely, however, that flows will be above normal through to mid-June. Flows will be adjusted as needed through June.
People should also stay away from the river system on June 10 and 11 for the high water release for the DFO release of Chinook smolts.
From May 30 through to mid-June, there should be no tubing on the Puntledge River with the exception of June 13 and 14. On those two days when the upper river fish migration flows are in place, the lower river areas below Powerhouse Road will be more typical. Flows may still be around 20-25 m3/s for those two days so please be cautious. It may be best for your safety to please wait until July when the snowmelt may be nearly depleted and river flows are lower."