The setback dike created on Mission Creek to help with flooding.—Image credit: Jan Vozenilek

Flood mitigation measures put to the test in Kelowna

Setback dike on Mission Creek and Mill Creek diversion both used on the weekend

While high water levels in both Kelowna’s Mill Creek and Mission Creek created localized flooding over the weekend, two mitigation measures—one created in the mid-1980s and the other just recently completed—appeared to have helped, a least a little.

As part of the recent Mission Creek Restoration Initiative, the newly created setback dike, between Casorso Road and Gordon Road, helped contain some of the water flowing down Mission Creek towards Okanagan Lake, said Todd Cashin, who was involved with the project.

Cashin, who works in the city’s planning department and who is currently the planning section chief at the Emergency Operations Centre set up to deal with the flooding, said higher than normal water volumes in both creeks at the same time is rare.

Fed by heavy rain late last week and snow melting quickly at higher elevations due to unseasonably warm weather, a torrent was created in both creeks that led to the flooding.

In addition to the setback dike on Mission Creek, a diversion structure funnelling water from Mill Creek to Mission Creek is also being used.

The diversion is a 2.4-metre-wide concrete box culvert that runs from Mill Creek just off Enterprise Way near Hunter Court to Mission Creek near the ECCO Centre in Mission Creek Regional Park on Springfield Road.

It was created in 1986 and is gravity fed.

Cashin said while some local flooding along Mill Creek has historically been reported and certain areas of Mission Creek, where other creeks flow into it, normally experience some flooding in the spring, what the city saw on the weekend was much worse this time.

“Crews are reporting this to be the worst in recent memory,” he said.

City crews, and their counterparts with local irrigation districts, are out in force clearing drains and culverts and trying to create paths for the water to disperse, without flooding more, Cashin said.

But he said Mother Nature may be ready to act against city efforts.

Environment Canada is saying the area can expect more warm weather that could affect snow melt at higher elevations, followed by significant rain over the next week.

“We’re telling people this isn’t over,” said Cashin.

He said with creeks running high, the ground saturated and all major lakes here either at, or about to reach, full pool, “the bucket’s full.”

“The water has nowhere else to go,” he said, predicting there could be more flooding in store for the area.

As a result, the city is urging property owners to be prepared and to sandbag their properties as much as possible now, before a second deluge hits.