The situation at Solana Key has improved considerably since this photo was taken May 11. The town is now planning for the return of residents. (Richard McGuire photo)

Osoyoos Lake and the Similkameen River have fallen significantly in recent days and the sharp rise predicted over a week ago hasn’t materialized.

As of 1 p.m. Wednesday, Osoyoos Lake was at 915.20 feet above sea level, its lowest level since Wednesday, May 9. That’s more than a foot lower than the high mark of 916.45 reached the morning of Saturday, May 12.

The drop of the Similkameen is even more dramatic, falling to 17,500 cubic feet per second (cfs) Wednesday morning as measured at Nighthawk, Washington for the U.S. Geological Survey.

The river normally is a predictor of rises and falls of Osoyoos Lake, and it reached a high of 32,300 cfs on May 10, just two days before Osoyoos Lake peaked.

While renewed flooding could still occur, much of the snowpack responsible for earlier flooding has now melted. Nonetheless, the ground is saturated, and a heavy rainfall could still cause problems.

Results of the May 15 snow survey released by the B.C. River Forecast Centre on Tuesday show that dramatic snowmelt has occurred over the first two weeks in May due to extreme temperatures.

While this led to widespread flooding, it has also greatly reduced the threat posed by remaining snowpacks.

In most parts of the province snowpacks are now below normal for this time of year, however in areas such as the Okanagan that were seriously affected by flooding, snowpack is still higher than normal.

The Okanagan is at 126 per cent of normal, but the Similkameen, which has a much bigger impact on the level of Osoyoos Lake than the Okanagan, now has only 56 per cent of normal snowpacks for this time of year.

There is very little snow at low elevations currently. Between 30 and 60 per cent of snowpack has melted from mid-elevations and about 10 to 30 per cent has melted at upper elevations, based on May 15 survey results.

Last week, forecasters were predicting a new peak level for Osoyoos Lake would be reached last Friday, with some even speculating it could surpass 917 feet above sea level.

While the lake did rise back to 916.32 feet on Friday, it was still an inch and a half below the May 12 high, thanks to cooler weather than predicted.

“Ongoing flood risk from this season’s snowpack is primarily associated with the remaining mid-to-upper elevation snowpack,” said the bulletin. “In low-to-mid elevation watersheds, snowmelt risks have subsided. Except for watersheds draining high mountain terrain, risks from snowmelt are expected to last another one to three weeks.”

This includes the Okanagan Lake system, the River Forecast Centre said.

Referring to the Similkameen, along with several other B.C. Rivers, the River Forecast Centre said on Friday: “The likelihood of these rivers flooding from only snowmelt contributions has now dissipated, and the ongoing risk is associated with widespread rainfall.”

Meanwhile, the Town of Osoyoos issued a bulletin on Tuesday saying it is actively working on a plan to get residents who were evacuated back into their homes.

“Residents are asked to remain patient as the process continues,” the town said.

The town has not issued any new evacuation orders since May 11, when it added 30 addresses to the 23 already under evacuation.

Last Thursday, it did issue evacuation alerts for some properties in the Cottonwood Drive, Lakeshore Drive and Lacey Point areas. An evacuation alert is a warning that residents might have to evacuate at short notice.

As of Tuesday afternoon, none of these evacuation orders or alerts has been rescinded.

The town said that water has been successfully removed from Solana Key’s roadway with Gabion baskets and pumps.

“Crews are now cleaning up the area and a rapid damage assessment crew will be heading out to these properties to assess them for damage and clear them for occupancy,” the town said. “Please be patient during this time and only allow staff carrying proper credentials into your home.”

The town said it hopes the evacuation order will be lifted before the end of this week. FortisBC Gas is also working with the town to assess the safety of turning gas back on.

Harbour Key is still affected by a flooded street and some Cottonwood properties are impacted.

They will not be assessed for re-entry until the water recedes, except for two properties, the town said.

Residents who have chosen to stay home despite the evacuation order must not use sewer services, the town said.

“Some residents in the area have been experiencing sewer backup in their homes due to use of the system by their neighbours,” said the town. “Please be respectful of your neighbours and discontinue use.”

The town will look at enforcement measures if residents continue using sewers.

Properties at 6404 Cottonwood, 7702 Main Street, one property on Kingfisher Drive next to Legion Beach and 69 units at Paradise Park remain under evacuation until further notice, the town said.

The public is advised that sandbags must be left in place until further notice.

“There is still a potential that the lake may rise and until that threat is over, all remedial action taken to protect your properties should remain,” the town said.

The evacuation alerts remain in effect until further notice.

RICHARD McGUIRE

Osoyoos Times