Drought plan vital for Okanagan water utilities

As loonie-sized plops of rain fell and immediately evaporated from the hot, dry, sidewalks outside, inside the rehearsal hall at the Kelowna Community Theatre, more than 100 politicians and water purveyors from around the Okanagan talked about drought planning, Thursday.

Oliver Mayor Stu Wells, who is also vicechairman of the Okanagan Basin Water Board which put on the day-long workshop, admitted he was "a little bit petrified" about how this year is shaping up.

"This rehearsal room is perhaps appropriate and that’s how we should see this day;’ he said.

”Drought is coming to a neighbourhood near you. It’s our responsibility to plan for this and to have answers for when drought comes:’

Brian Symonds, acting head of the water stewardship division in the environment ministry, said this situation was predicted earlier in the year, when about a third of the normal inflow to Okanagan Lake was measured, due to low snowpacks and well below normal spring precipitation.

Topped off with a hot, dry summer, he said, "things are not looking good and, the long-term forecast is for continued low precipitation and hot temperatures through September."

Okanagan Lake is down 40 centimetres from where the ministry would like it to be. ”And, we, won’t be able to bring it back in a hurry," Symonds said. ‘

He said there is no official declaration of drought, but the current situation qualifies under the hydrologic definition of drought. "Consider how long this could last and how ready are you for that:’ he said.

Since the Okanagan Valley largely depends on the runoff from snow melt, he noted that ground water levels are just as important as stream flows.

The ground acts as a sponge and melting snow soaks into the sponge to soak it before any runs off.

That’s part of the reason he believes there was inadequate runoff this spring to fill reservoirs such as Okanagan Lake, and upper reservoirs in some districts.

Bob Hrasko, vicechairman of the Water Supply Association of BC, explained that Okanagan Lake is the barometer for the basin and said it needs to be controlled so that only the 1.5-metre top layer of the lake is used each year so the lake isn’t mined to the point where it can’t be re-filled.

At the extreme end of that scenario would be the need for a new floating bridge to replace the one year-old Bennett Bridge which connects Kelowna and West Kelowna, he commented.

With the Okanagan being a semi-desert climate there’s not really a lot of usable water in the mainstem valley lakes. "It’s flow-through water," he explained.

The Okanagan Valley draws from a watershed that is 8,000 square kilometres, with the most precipitation falling in the hills above the valley.

Users include a large agriculture component, 58 per cent of the water used, and most districts rely on storage and irrigation licences. Outdoor uses amount to 82 per cent of the water used, while three-quarters of the water used is managed by water utilities,

Dean Watts, senior water use biologist with Fisheries and Oceans Canada, warned that there are optimum depths and velocities in streams for spawning and migrating fish as well as issues around’ the potential for fish to be stranded when side channels dry up.

Small to medium streams are particularly vulnerable, and in them temperature is also critical and becomes more variable as water levels drop. Native fish such as trout and kokanee require cold water for survival and are vulnerable when the water temperatures rise above 20 or 21c. As more water is extracted, the water gets hotter in summer.

OBWB executive director Anna Warwick Seat·s warned the valley’s economy suffers from even patchy shortages of water, but it’s important to "balance the water chequebook” she said. ”There’s no mechanism to work together to protect the lake."

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