Flood danger critical in next few days

Sudden hot weather has caused local creeks to fill with snowmelt from high elevations around the valley.

A ‘high streamflow advisory’ for Mission Creek has been issued and it could be upgraded to a ‘flood watch’ if the current hot weather continues, advises the head of the River Forecast Centre, Dave Campbell.

“The next few days are critical,” he said.

A flood watch warning means river levels are rising rapidly and that minor flooding in low-lying areas is possible.

The next step would be a flood watch warning, which means residents should be aware there  is the potential for river banks to be ‘overtopped’ by water.

A flood warning is the next step, and that means it is imminent, explained Campbell.

In the past week the weather has gone from winter, with a dump of snow on the Coquihalla and in surrounding hills, to summer, with unseasonably high temperatures.

“It was a quick transition,” agreed Campbell, noting weather at higher elevations went from a snowstorm last week to a 24-hour snowmelt this week, affecting a snowpack that is nearly 30 per cent above normal in the Mission Creek watershed.

That snowpack is ‘ripening’ or changing in density as the melt begins to get underway and now it’s really into it, he said.

Tuesday/Wednesday overnight temperatures high up in that watershed stayed at 10 C while daytime temperatures were 20 C. Valley temperatures have gone above 30 C, which is more than 10 degrees above normal.

Doug Lundquist, meteorologist with Environment Canada says the forecast is for continued hot weather until Saturday or Sunday when it should cool down as a cold front moves in from the west and northwest.

There’s a slight chance of showers, but he doesn’t think there will be much rain—such as there could be if that front was moving in from the south.

No records have been broken in Kelowna for high temperatures, although it’s been close the past few days, he said.

Looking well ahead to the week of May 16 to 23, he said there’s a high probability of above average temperatures returning, but not as hot as this week’s weather, and it’s expected to be a dry pattern.

This year’s snowpack measurements as of May 1 are well above normal on the east side of the lake, but they’ve also risen from below normal to just above normal on the west side of the lake with several dumps of snow in the past month or so.

Higher than normal inflows to Okanagan Lake are forecast  this year, said Campbell.

The Central Okanagan Emergency Program warns residents in flood-prone areas to prepare to protect their properties as conditions could change rapidly during spring runoff.

Bruce Smith, communications officer for the regional district said sand and sandbags have been dropped off for property owners in the Casa Loma, Green Bay and Whitworth Drive areas in West Kelowna and officials continue to monitor weather patterns and water levels of local creeks, streams and lakes.

Rapidly rising water has forced the closure of two underpasses along the Mission Creek Greenway, at the Casorso Road bridge and on the south side of Mission Creek at the Gordon Drive Bridge.

Pedestrians and cyclists are advised to use caution crossing Casorso Road and motorists are warned to watch for greenway users who may be crossing the road in the area until the underpass is re-opened.

The abandoned Muttitt property off Highway 33 in the Joe Rich area is flooded, said Smith, but he said there are no services to the property and the property-owner refused permission for anyone to go on the property to assess the situation.

The provincial transportation ministry, when asked about concerns regarding the possibility of structures from that property being swept downstream, responded: “Ministry staff have assessed the site and do not believe there is a risk to the highway bridge if structures on the Muttitt property are swept downstream.”

Information and pamphlets on flood preparedness, including a recommended method for sandbag diking are available from both the regional district office and the City of Kelowna firehall on Enterprise Way, as well as on the Regional Emergency Operation Centre website at: www.cordemergency.ca

Anyone who notices a potential problem or flooding concern in the Central Okanagan should call regional fire dispatch at 469-8577. Sandbags are available at local firehalls for property owners facing imminent danger from flooding.

People are also warned to use caution around all water bodies because water levels could rise quickly and unexpectedly. Keep pets and children well back from creek banks.

Boaters on the lake should also be on the lookout for floating debris carried into the lake from rising and fast-flowing streams.

jsteeves@kelownacapnews.com