Local News

NCH Reopening Starting Target Dates Set for March 26

Jeff Adamson, WSDOT

Mar 23, 2018

March 26 from the west side and April 9th from the east are the target dates to begin the spring clearing effort to reopen the North Cascades Highway. The dates were chosen following an assessment by WSDOT staff March 19th.

The west side crew will begin clearing from the Diablo gate on Monday. The east side crew will begin clearing at Silver Star gate on April 9th. The west side crew, using a snowblower attachment mounted on a front end loader, will start clearing at Diablo where snow is less than a foot deep. Due to the difference in topography, once the first 15 miles of roadway is clear, the crew goes back and repairs pavement damage, removes concrete jersey barrier (placed when SR 20 closed last November in order to protect roadway facilities from slides), replaces guardrail and signs removed during the closure, clears rocks and debris and clear and shape shoulders and ditches. Once that work is complete in about three weeks, the crew will resume travel lane clearing to Rainy Pass and beyond. Work from the east begins later as full avalanche chutes make the highway below too hazardous. Warming temperatures over the next two weeks are expected to cause natural slides clearing many chutes.

Last Monday morning, March 19, the North Central Region Avalanche Crew and Area 3 Twisp Maintenance Management assessed the condition of the road and the avalanche potential from Silver Star gate to Rainy Pass. Depth measurements were taken, snow caves were dug to evaluate the stability of the layers of snow in the chutes, temperatures taken and a great number of observations recorded. The actual starting date target is the result of the assessment coupled with forecasts for the days and weeks ahead, equipment and staff availability and contractors. Predicting a reopening date is impossible as so many of those elements can and have caused days and sometimes weeks of delay. Things such as bad weather that didn't match the forecast, serious equipment damage, crew issues such as a nasty flu are just a sample of what has gone wrong during reopenings over the last 46 years since the highway first opened.

Last year the clearing work started April 10th and the reopening wasn't until May 16th, well past the fishing season opener and Winthrop's 49er' Days Festival. Most years warmer temperatures allow the clearing to start before the end of March and the opening comes in 4 to 6 weeks by late April or early May. Don't expect an early reopening this year.

As noted, the snow on the road is only part of the picture. Many of the measurements below avalanche chutes were on par or less than an average year, but some of the chutes had released snow and their depth far exceeded the norm. Examples: Cutthroat Ridge #4 had 10 feet this year, but only 5 last year. CR#6 on the other hand had 13 feet this year compared to 25 feet measured during last year's assessment. Liberty Bell #3 had 50 feet this year and 35 last year, while Liberty #1 only had 20 feet of snow below it on the road this year compared to last year's 45 feet.

The weather and temperatures will determine when the snow still in the avalanche chutes comes down, but the assessment did reveal there's a persistent weak layer in the snow higher up in the chutes in zones from Cutthroat to the Beebe and Ruby zones west of Rainy Pass.

Once the clearing work begins, the highway is closed to recreationists Monday through Thursday. Friday, Saturday and Sunday you can snowshoe, ski, snowmobile and even bicycle beyond the gates, but we ask you report any vandalism you see when you get back in cell signal range.