Spring Road Clearing

map of plow progress on road
Plow progress on main park highway 7/26/17
2011 Road opening
Rotary plow at the southwest entrance

NPS Photo

Road Opening Process

The park highway will open to through traffic once the final section between Bumpass Hell and Devastated Area is cleared, rockfalls are cleared, and all lingering ice is melted. The road opening process may be delayed by late snow storms as well as other factors including:
  • Heavy snowpack with deeper snowdrifts in some areas
  • Trees that have fallen across the road and been buried in the snow
  • Rockslides over the highway when the snow begins to melt
  • Snow avalanches over cleared sections of the highway
  • Snow storms during the operations
  • Lingering ice once snow is cleared

2017 Road Clearing Operator Log

Log updates are posted when reports are received from operators in the field. The latest update may not reflect the current status. The road crew works Monday through Thursday, 10 hours per day.

April 4 - Tuesday, Snow removal from the Manzanita Lake Campground loops started today. This will likely take the remainder of this week to complete. Weather permitting, next week we will start on the main road towards Devastated area and hope to have it completed by around the 21st. If all goes well and the weather works with us, we hope to start at the southwest entrance at the Kohm Yah-mah-nee Visitor Center around May 1.

April 18 - Snow clearing to Devastated Area from Manzanita Lake was relatively smooth, with just a couple of snowstorms delaying progress slightly. The average snowdepth was about 5 feet. The road will open to the Devastated Area soon pending some parking area clean-up and restroom preparation. Also, after clearing a large tree which fell blocking the road to the Manzanita Lake boat launch, the parking lot and launch are now open. Stay tuned...

May 5 - After staging equipment to get ready for clearing at the southwest entrance from the Visitor Center, we began on Wednesday May 3. We started digging through about 11 feet of snow. In two days, we only were able to clear about 200 yards. We will resume Monday morning...

May 21 - On 5/12 the crew rounded Diamond point and gained the first views of Lassen Peak. Check out the Facebook Live recording of us at work! For the week of 5/15, the crew paused work on the park highway to clear the Warner Valley road (which is closed to vehicles at the park boundary until the road dries sufficiently) and assist with seasonal water treatment operations. We will be returning to Windy point on Monday, 5/22.

May 27 - The crew is making slow, but steady progress, working our way into a more difficult section of the road. We ended the week at the lower switchbacks at Little Hot Springs Valley, about 1 mile from Diamond Point. It takes three opeartors in three different machines moving snow to expose bare pavement. The lead bulldozer, pushes snow off the park highway. A second bulldozer pushes off an additional layer down to about 4 feet above the pavement. The rotary blower then clears the final layer of snow. We will resume Tuesday. May 30. Have a safe and fun weekend!

June 3 - We worked our way to the upper switchback above Little Hot Springs Valley this week, about another mile beyond the lower switchback. The snow is getting deeper as we push up in elevation. It is about 10 - 12 feet at this spot. Also, there are a lot of trees fallen across the road slowing progress. Monday, we will begin the treacherous Emerald side hill. Stay tuned...

June 10 - A lot has happened since our last post! Yesterday, the road to Warner Valley opened. It has received a bit more damage from runoff this year than prior years. Consequently, there are deep potholes and washouts up to 6 inches. Also a bit of washbording. Low-clearance vehicles are not advised. Trailers and RVs may also experience difficulty. Please drive slow to help preserve the road and your vehicle! Along the main park highway we cleared through Emerald Side Hill in two days without any problems and are working our way toward Bumpass Hell parking area. Despite the amount of snow, progress has been steady. Check out the Facebook live recording.

June 17 - We made it about a mile and a half from the Emerald side hill to the Bumpass
Hell parking lot this week. There is about 10 feet of snow there. Also, we will decide next week if we will work on clearing the parking area or push ahead on the road. It could be more helpful to push ahead on the road and allow the sun to do some of the work in melting before returning to the parking area. There will be an update next week on the decision. If you want to see Lake Helen, expect a snowy sight! Not even the edges of the lake have melted yet.

June 24 - After a delay with equipment breakdown, we are now working at the deepest snow on the road, the Lake Helen drift and approaching the road summit at 8,512 feet.There is about 35 to 40 feet in the drift this year! We haven't seen that amount since 2006! Our We were hoping to have the entire road completed by Independance weekend, but now our estimate of completion with road clearing is mid-July.

July 7 - The park highway has been opened to the Bumpass Hell Parking Area on the south side of the park. However the trail into Bumpass Hell will remain closed until the snow melts off of the trail. The park road crew is continuing to plow through the deep snow past Lake Helen and are approaching the Lassen Peak Parking Area. On the north side of the park crews have worked their way to Summit Lake area, but the road remains closed at Devastated Area until parking areas and turn arounds are cleared.

July 16 - With the help of Cal-Trans District 2, there has been great forward progress on road clearing. Cal-Trans made it up to the Kings Creek Meadow area from the north, but suffered equipment break down last week. Also, the road has opened 3 miles beyond Devastated Area to Summit Lake. Progress on the Lassen Peak Parking area is moving along. It won’t be long before north and south meet. Once parking lots are cleared, culverts repaired, and fallen trees and rocks are cleared from the road, it will finally be open for the season. We anticipate opening the week of the 24th. Stay tuned…
Road clearing on Emerald side hill
Snow plowing below Emerald Lake

NPS Photo

When Will the Highway Open to Through Traffic?

Road clearing operations began April 4, 2017. Sections of the park highway will open when it is safe and there is sufficient parking for vehicle traffic. The road is expected to open to vehicle traffic late July.

The park highway encompasses 30 miles of stunning views through twisty hair pin corners, high elevations and steep grades. To attempt road clearing throughout winter would be impossible and extremely hazardous for plow operators and drivers. The park highway traverse avalanche prone slopes with up to 2,000 foot drops and can hold a snowpack up to 40 feet deep. With the park's high elevation and exposed passes, ice and blowing snow would be a constant issue.

Clearing of the park highway usually begins in April and continues for about two months before the road opens to through traffic. Predicting when the road will open is not possible, even in late spring, because weather in April and May can affect plowing progress significantly. See the chart below for opening and closing dates since 1980.


Spring Road Opening Dates - 1980 to Present


Date plowing began from southwest

Date road opened

Date road closed

1980 April 20 May 29 November 21
1981 April 20 May 21 November 3
1982 April 19 June 18 October 25
1983 April 18 July 2 November 10
1984 April 23 June 4 October 28
1985 April 14 May 18 October 21
1986 April 7 June 7 November 24
1987 April 20 May 15 November 13
1988 April 2 May 20 November 7
1989 April 3 June 6 October 23
1990 April 1 April 28 November 14
1991 April 7 May 24 October 22
1992 April 6 May 14 October 29
1993 April 12 June 28 November 10
1994 April 3 May 20 November 7
1995 March 19 July 21 November 21
1996 April 1 June 12 October 18
1997 April 7 June 5 November 14
1998 April 5 July 12 November 10
1999 April 12 June 11 November 19
2000 April 3 June 2 November 17
2001 April 2 May 10 November 15
2002 April 1 May 22 November 13
2003 March 26 May 23 November 7
2004 March 11 May 27 October 28
2005 April 4 June 2 November 8
2006 April 3 July 6 November 11
2007 April 2 May 18 December 6
2008 March 31 May 18 December 12
2009 April 13 June 4 November 18
2010 April 19 July 8 October 23
2011 April 19 July 16 November 22
2012 April 21 June 1 November 19
2013 March 21 May 24 December 18
2014 April 3 May 19 December 1
2015 March 31 May 3 November 8
2016 April 18 June 12 October 30
2017 April 4 July 26

Last updated: July 26, 2017

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Mailing Address:

PO Box 100
Mineral, CA 96063


(530) 595-4480

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