WSDOT North Cascades Highway Update - Highway 20

Published: February 24, 2010

The February 22 assessment trip to the North Cascades produced a target date of March 22 to begin the reopening effort.

The assessment team and observers arrived at the Silver Star gate about 8 a.m. yesterday.  It was clear and 14 degrees.  Avalanche team members, John Fleckenstein and Brandon Levy took the snowmobiles and headed west to the other side of Rainy Pass.  Avalanche Control Chief Mike Stanford drove the Sno-Cat with 3 passengers ? Twisp Maintenance Supervisor Don Becker, North Central Region Assistant Administrator for Maintenance, Dave Bierschbach and our ?new? Acting Regional Administrator, Dan Sarles.  (Don Senn retired last fall after 33 years.)  Dan has been in NCR on the Construction and Engineering side for the last couple of decades, but this was his first winter visit to the North Cascades.

He was treated to beautiful clear skies and sunshine, but nothing approaching ?normal? snow conditions.  Snow and debris amounts are lower than in previous years. They dug a snow pit near the summit that revealed a shallow and stable snow pack, right now.

They found a surprising amount of huge ?hoar frost? crystals ? many as big as playing cards (up to 3.5?) that could become a problem on some of our avalanche paths depending on the amount of new snow we get in the next month. (It would become an immediate unstable slip layer.  However, if we don't get any significant new snow between now and the opening, most of the avalanche zones should melt back without dumping any more snow or debris on the road.  That leaves just the eight * chutes that historically release more of their snow onto the road as the spring temperatures rise?.  (*Cutthroat Ridge #6, 7, 8, 11 & 12 and Liberty Bell #1, 2 & 3).

The reopening starting date is two days after the (Mar. 20) first day of spring - about the same as the last four years.  We really can't start any earlier since our mountain pass maintenance crews (Leavenworth, Stevens, Blewett and Twisp) are on their round-the-clock winter schedule until Mar. 15.  That?s (obviously) the soonest we can release any of the snow blowers and bring in the other equipment and crewmembers we'll need.  The Mar. 22 start date provides four working days for the equipment to go through inspection, service and modifications, plus transport time to Twisp.

The assessment team took snow depth measurements from Silver Star Gate(MP 171) all the way to the bare pavement they found about nine miles above the west side closure gate (MP 134).
?         Silver Star Gate - 3.3.? compared with 2? last year.
?         Cutthroat Ridge #1 - 3.3? compared with 7? last year (and 25? in ?07).
?         Cutthroat Ridge #6 - 9? compared with 25? last year.
?         Cutthroat Ridge #12 ? 6? compared to 25? last year.
?         Liberty Bell #1 ? 12? compared to 40? last year.
?         Liberty Bell #2 ? 10? compared to 30? last year.
?         Liberty Bell #3 ? 12? compared to 40? last year.
?         Washington Pass ? 6? compared to 5 ½? last year.
?         Rainy Pass ? 3.3.? compared to 6? last year.

The lower than normal snow amounts should make for a faster than usual opening - maybe as few as three weeks instead of the usual six.  El Nino has affected our snowpack; especially below 3500 feet elevation. The avalanche crew, however, is looking warily ahead to next year as history has shown us that the winter following an El Niño year is often a big one.

The photos are available on the WSDOT Flickr site (check out the Hoar Frost pictures!).