An update since BC Hydro’s public notice on Friday about the forecasted weather systems and Campbell River hydroelectric operations. Since last week, BC Hydro has been tracking the two sub-tropical storms forecasted to hit the region this week. Unfortunately the storms are now forecasted to be much stronger and will hit the Campbell watershed hard. BC Hydro’s weather forecasting and hydrology modelling, as of today, has seen a large increase in rainfall and forecasted inflows. The Monday-Tuesday storm is the strongest. Precipitation tonight may fall continuously at 10 mm per hour for several hours.
With the high ocean tides taking place in the morning each day this week, BC Hydro is concerned about these storms and the potential for isolated flooding as the week progresses.
We are forecasting daily water inflow averages into the Upper Campbell Reservoir/Buttle Lake to be 900 and 750 m3/s on Tuesday and Wednesday. That means hourly peaks may hit 1400 m3/s. It also means the uncontrolled Quinsam River flow may be high. Flooding along the Campbell River downstream of the confluence with the Quinsam River can begin at around 450 m3/s but is dependent on tides and storm surge from wind. There are winds from these storms that may cause some storm surge.
Since the weekend, BC Hydro is spilling water down Elk Falls Canyon and that looks to continue for at least the next 11 days to balance high reservoir elevations and flood risk along the Campbell River. The Upper Campbell Reservoir is currently at 219.2 metres. The reservoir may crest around 221 m on Thursday or Friday. The available reservoir storage will be taken up fast in the next few days, and with it, BC Hydro’s flexibility to back off during high ocean tides.
BC Hydro will operate the John Hart dam and generating station in consideration of the high ocean tides each morning and unregulated Quinsam River discharge. BC Hydro will endeavour to keep river flows above the Quinsam River at or below 350 m3/s. This means the Elk Falls Canyon flow may reach 230 m3/s as BC Hydro modifies its operations as needed to deal with these major storms. As of right now the canyon flow is 110 m3/s. The public is advised to stay away from the Campbell River and Elk Falls during these high flows.
We have reached out to the City of Campbell River, Strathcona Regional District and Emergency Management BC so that we are all coordinated.