High risk at Keremeos slide site
Residents of a Keremeos RV park are back in their homes following a rock slide earlier this month that chased them away, but an engineering assessment of the troublesome hillside in question suggests the danger hasn’t passed yet.
The slide on Jan. 9 sent boulders tumbling down a steep slope, across Highway 3 and into the Eagle Campground and RV Park at 3169 10th Ave. just west of Keremeos. No one was hurt, but a shed, fence, canopy and other equipment were damaged.
Residents were ordered evacuated that same day and only allowed to return home Jan. 27.
The campground is within the jurisdiction of the Regional District of Okanagan-Similkameen, which hired Ecora Engineering to complete a hazard assessment at the site on Jan. 16. The results were troubling.
“Based on the observations made during our site reconnaissance and review of historical documentation, the probability of reoccurrence of rock fall from the source zones above the subject property is considered very high as there are no permanent mitigation works in place and is therefore considered an ongoing threat to residents’ life-safety,” concludes the report, which the RDOS released publicly.
Using decades’ worth of old aerial photos, Ecora was able to pinpoint a similar slide at the site in 1987, before the campground existed, plus two more in 1997 and 1998.
“It is unknown when the (campground) was approved for development and what guidelines would have applied at the time of approval,” notes the report, but the site’s lack of protection against rock slides “does not meet the broadly accepted landslide safety criteria with respect to residential development.”
Ecora pinpointed the origin of three large boulders that hit the campground to a rock outcrop high above a fan of fallen debris at the base of the slope on what is Crown land.
The company also pointed to unseasonably warm data as a possible trigger for the event.
In the seven days preceding the slide, according to the report, the average daytime high at the site was 6.9 C, well above the historical average of 5 C, while the area also got 19 millimetres of rain over the same timeframe.
Ecora concludes its report with recommendations for mitigation works at the site, such as a ditch and berm or steel mesh to keep rocks from reaching the highway, and noted any such work “will likely be substantial in size and cost.”
And according to the RDOS, it’s not government that’s responsible for those costs.
“The Regional District of Okanagan-Similkameen distributed the geotechnical assessment to assist property owners and residents in making an informed decision about next steps,” the local government said in a statement Monday.
“Potential mitigation measures are the responsibility of property owners.”