From record dry to record wet.
That’s the news over the past year from BC Hydro’s water supply records that date back about 50 years.
A water supply year extends from October to September. The 2013/2014 season to February was the driest on record without a significant storm.
“This translated into water conservation efforts and a low snowpack that hugged near record lows,” BC Hydro communications officer Stephen Watson said.
The opposite is true for 2014/15 — easily the wettest year to date. A handful of significant subtropical storms, including a record-breaking December storm that pounded the Comox Valley and other parts of the West Coast, generated high flows in rivers and streams. However, mild temperatures and rain have melted snow in upper elevations. The resulting snow pack is nearly identical to where it was this time last year, at about a third of normal. Mid-elevation snow may be non-existent, Watson said.
“BC Hydro has been generating power at full capacity this year compared to last year with all the rain, and that’s good news, though we have been hard-pressed on flood risk management operations,” Watson said. “Too much of something is not a good thing, and that applies to all this rain.”
Since October, Watson notes the water BC Hydro has spilled downstream for flood risk management would fill the Comox Lake reservoir 4.5 times.
“With the extreme conditions we’ve had this winter I think our operational decisions have been the best possible,” he said.
BC Hydro is considering the lack of snow melt this year as it looks ahead to fish habitat coverage and water-use interests. Little run-off from the mountains presents difficulties in maintaining adequate river flows for fish.
“It goes to show the balances BC Hydro has in its operations from fish habitat flows and flood risk management to domestic water supply in the summer,” Watson said. “Each year can present very different challenges, and that’s been the case in spades lately.”
BC Hydro was back to operating normal river flow conditions on Friday.