The biggest local landslide in decades has closed Robert Service Way for an indeterminate amount of time.

The clay banks near the eagles’ nest gave way at approximately 3 p.m. Saturday, sending a torrent of mud and debris across the road and the Millennium Trail and onto the ice on the Yukon River.

The road has been closed since, as City of Whitehorse officials try to gauge how dangerous the situation is. Work to clean up the mess won’t begin until the site is deemed safe.

A video circulating widely on social media shows a white vehicle driving through the area just ahead of the slide as the middle of the clay cliffs give way.

Whitehorse Fire Chief Jason Everitt told the Star the first calls came in to the fire department just before 3 p.m.

Crews responded immediately – ironically, on the dawn of Emergency Preparedness Week.

The area was cordoned off, and several pedestrians along the Millennium Trail were interviewed in an effort to determine if anyone might have been caught in the debris. Fortunately, it appears there were no injuries, Everitt said.

It’s not the first time there have been mudslides in the area, but it’s apparently the first time the damage has been so extensive.

Debris has reached the shoulder occasionally, Everitt noted, but he wasn’t aware of it crossing the road in such volumes.

Mayor Laura Cabott also spoke to the Star this morning about the situation.

She confirmed no cleanup work has been started as yet as the site is not safe enough to do anything.

“We have to rely on the experts,” she said.

The city is flying a landslide specialist in to provide advice. That person could arrive as soon as today.

Cabott said the city has been monitoring the cliffs along Robert Service Way for the last couple of years as the snow load has increased.

Like Everitt, she said no one she’s spoken to remembers a similar situation along Robert Service Way – just smaller slides at various locations of the escarpment.

“There were a few slides last year, but nothing like this,” the mayor said.

It could take several days, at the minimum, before the road reopens, Cabott said.

She added she appreciated the co-operation of city residents while the situation is handled.

Cabott said the city has also reached out to the Yukon government for any assistance it can provide.

Panya Lipovsky, a surficial geologist with the government, said she was a little surprised to see a landslide so early in the season.

She said a slide of similar size occurred in June 2021, coming within 90 metres of Robert Service Way. That time of year is more typical for a mudslide.

Other comparable avalanches occurred in 1949, 1953 and 2000.

The slide in 2000 occurred in the cliffs above Marwell in the Takhini area.

The current slide is noteworthy and exceptional only because it spewed across Robert Service Way, which she said “was just in its way.”

Lipovsky said the slide is almost certainly due to the saturated soil from this year’s excessive snowpack.

As most people know, the cliffs are the remnant of a glacial lake dating back to the last ice age, which ended roughly 10,000 years ago.

The clay banks represent the bottom of that lake, which has since been steadily eroded.

There are three to five metres of sand covering the clay, and landslides happen when water seeps through the sand to the clay, causing it to separate.

The city has issued several updates to the situation via its website and social media.

“The area around the recent escarpment slide, which also includes the Millennium Trail and Airport Trail, remains unstable and is considered a high-risk, active site,” the first update stated on Saturday evening. “It will be closed until further notice, and the public is instructed to avoid the area.

“Barriers and signage are in place near the Robert Service Way Roundabout and the baseball diamond.

“Bylaw Services will also be on site throughout the night. City of Whitehorse crews continue to monitor the situation, and updates will be provided as they become available.”

On Sunday, an additional update was issued.

“Commuters are advised to adjust their travel plans, and use alternate routes or modes of transportation as a result of yesterday’s escarpment slide.

“Robert Service Way, from the roundabout to Miles Canyon Road near Yukon Energy Corporation, remains closed until further notice. Affected areas of the Millennium and Airport Trails are also closed.”

The update reads, “Commuters should anticipate delays in travel time and increased traffic congestion during these closures.

“Please allow for more travel time, and consider carpooling, using transit, choosing active transportation, or working from home, if possible.”

The update also stated, “Transit service to Lobird has also been affected with Route 5 now detouring along Second and Fourth Avenue, Two Mile Hill, and Hamilton Boulevard. Passengers should expect delays.”

“Standard Bus has also been informed, and alternate routes are planned for student transportation. Today is a PD day for students, so busing wasn’t affected.

“As a reminder, the area around the slide remains unstable and is considered a high-risk, active site. The public is instructed to avoid the area.”

Several people on social media said they weren’t surprised to see a landlside occur. They wrote they had noticed movement on the cliffs in the days prior to this slide.

Up until it ceased service to Whitehorse in 1982, the White Pass and Yukon Route used a railway track paralleling the clay cliffs beside Robert Service Way.

The danger of escarpment slides has been on the city’s radar for decades.

In the 1970s, for safety reasons, it began buying out the houses of residents living at the base of the cliffs and removing them.