Dry weather means lower water levels

Dryer than normal weather that reached near-record lows for rain in May means the Arrow Lakes won’t reach full pool this year.

  • Thu Jun 25th, 2015 5:00pm
  • News

Alex Cooper

Black Press

It’s good news for birds and beach lovers, bad news for those that want to get into the water.

Dryer than normal weather that reached near-record lows for rain in May means the Arrow Lakes won’t reach full pool this year.

That’s good news if you like to play on the Columbia River Flats, most of which should stay dry. It’s also good for nesting birds, who won’t see their nests get inundated.

It’s bad news for boaters, who might not be able to use their docks. Beaches might be super-sized, which is good if you just like to tan, but bad if you actually want to get into the water.

It could be bad for fish looking to spawn — they might not be able to get into their normal spawning channels due to the low water levels.

All of this is a result of a draught leading to 2015 being the third driest year in the Columbia Basin since record keeping began in 1960.

That was the message conveyed by BC Hydro, who hosted an open house on this year’s reservoir operations at the community centre on Thursday, June 11.

They had a series of poster boards filled with graphs, charts, infographics and maps, and two people from the operations centre in Burnaby were on hand. I was given an explanation of the situation by Peter McCann, a resource coordinator for the utility.

Across the entire basin — Canada and the U.S. combined — there is 69 per cent as much water as normal, he told me. In Canada the situation isn’t too bad, but across the border, they’re facing draught conditions. It’s the driest year since 2001, when water levels were 61 per cent of normal.

BC Hydro begins its water year in October. Overall around Revelstoke, it was actually wetter than normal until March. But then, April and May were extremely dry. Precipitation in May was about half the normal level.

Snowpack levels are slightly below normal in most of the Revelstoke area, but shrink the further south you go. In the United States, there’s pretty much no snow.

So, why won’t the Arrow Lakes reach full pool? That’s because a lot of the precipitation that fell before April has already run down the mountains, through the reservoir, and out to the Pacific Ocean. Because it was so warm this winter, snow fell as rain, so rather than accumulate and melt out in spring, it just ran straight into the river.

“All that runoff, we were not able to capture it in Arrow, unfortunately,” McCann told me.

One chart exemplified the problem. It showed water levels hovering around normal through early February, only to plummet downwards by June. The water wasn’t captured in the Arrow Reservoir because for a while it looked like a normal year.

Up north, some water was held back in the Kinbasket Reservoir and it is expected to reach full pool in mid-August.

The Arrow Reservoir is expected to peak this weekend, at around 432 metres elevation. Normal full pool is about five metres higher.

McCann said they will keep generating power at Mica Dam in order to keep Arrow levels up. He said they hope to keep the Arrow Reservoir at around 420 metres for most of the summer.

Recreation is the main reason BC Hydro tries to keep reservoirs levels up in summer, said McCann.

“People can’t use their docks, there’s beaches where people have to walk a kilometre or two to get to the water,” he said. “It impacts tourism on the lake.”

Ecologically, it’s good for nesting birds, but it could impact fish spawning.

The dry conditions shouldn’t impact power generation. McCann said that due to the U.S. being so dry, power prices are up, so BC Hydro will be generating power consistently and won’t have to spill water.

“There’s not going to be a shortage of power in the province,” he said. “We still have lots of water at present for that. If this prolonged draught goes on for a few years, then we’ll start to see some problems.”

What does the weather forecast have in store?

Lisa Coldwells, a meteorologist with Environment Canada, said we should experience a reprieve from the recent hot and dry temperatures over the next10 days. The long-range forecast for the rest of summer calls for hotter than normal temperatures, with normal amounts of precipitation.