Spring Road Clearing

A yellow snowplow clears snow backed by a snow-covered mountain
A snow plow clears snow near the Devastated Area.
 

Annual spring road clearing operations began on March 6 and concluded on April 30, 2020. Road crews have completed the initial snow removal on the 30-mile park highway and will continue with additional spring road maintenance including sweeping, cleaning culverts, installing signs, and clearing rockfall. Lassen Volcanic National Park, including the park highway, remains temporarily closed due to COVID-19 response.

Current road status | Routes around the park

 

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A rotary snow plow throws snow from a road lined by conifers
A rotary plow on the park highway in the Northwest Area of the park on April 3, 2019.

Road Clearing Process

Clearing the park highway is no quick or easy undertaking! Snow accumulates on the 30-mile park highway throughout the winter season (typically November through April). Snow depth can reach up to 30 feet at the highest elevations, with drifts occasionally reach as high as 40 feet. The highway may open in sections as conditions allow and as clearing operations continue. It will open to through traffic once it is safe for vehicles, not just only when it is cleared of snow. The road clearing process can take up to three months due to numerous factors including:

  • Heavy snowpack with deeper snowdrifts in some areas

  • Trees and boulders 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 (and additional accumulation) during the operations

  • Snow removal in parking areas

  • Road and road shoulder repairs

  • Lingering ice once snow is cleared
  • Equipment repair
 
 
Road clearing on Emerald side hill
Snow plowing below Emerald Lake

NPS Photo

When Will the Highway Open to Through Traffic?

Snow removal from 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. The park highway encompasses 30 miles of stunning views through twisty hair pin corners, high elevations, and steep grades. The park highway traverses avalanche prone slopes with up to 2,000 foot drops and can hold a snowpack up to 40 feet deep.

 

2020 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 30 - Road crew has completed the initial snow removal from the park highway.

March 6 - The park highway is plowed between Loomis Plaza and Devastated Area (10 miles). There is still a thin layer of snow/ice on this cleared section, which should melt out in the next week or so depending on weather conditions. Road crew is clearing snow from the Manzanita Boat Launch parking area. Road crew is moving equipment to the Southwest Area today and will begin clearing at Kohm Yah-mah-nee Visitor Center next week.

 

Spring Road Opening Dates - 1980 to Present

Year

Date plowing began from southwest

Date road opened

April 1 Snow Depth at Lake Helen (8,000' elevation)

Date road closed

1980 April 20 May 29 231" / 19.3' November 21
1981 April 20 May 21 149" / 12.5' November 3
1982 April 19 June 18 266" / 22.2' October 25
1983 April 18 July 2 331" / 27.6' November 10
1984 April 23 June 4 175" / 14.6' October 28
1985 April 14 May 18 163" / 13.6' October 21
1986 April 7 June 7 195" / 16.3' November 24
1987 April 20 May 15 138" / 11.6' November 13
1988 April 2 May 20 98" / 8.2' November 7
1989 April 3 June 6 223" / 18.6' October 23
1990 April 1 April 28 106" / 8.9' November 14
1991 April 7 May 24 151" / 12.6' October 22
1992 April 6 May 14 127" / 10.6' October 29
1993 April 12 June 28 225" / 18.8' November 10
1994 April 3 May 20 101" / 8.4' November 7
1995 March 19 July 21 287" / 23.9' November 21
1996 April 1 June 12 171" / 14.3' October 18
1997 April 7 June 5 135" / 11.3' November 14
1998 April 5 July 12 250" / 20.9' November 10
1999 April 12 June 11 194" / 16.2' November 19
2000 April 3 June 2 178" / 14.9' November 17
2001 April 2 May 10 109" / 9.1' November 15
2002 April 1 May 22 166" / 13.9' November 13
2003 March 26 May 23 185" / 15.5' November 7
2004 March 11 May 27 187" / 15.6' October 28
2005 April 4 June 2 173" / 14.5' November 8
2006 April 3 July 6 266" / 22.2' November 11
2007 April 2 May 18 112" / 9.3' December 6
2008 March 31 May 18 132" / 11' December 12
2009 April 13 June 4 146" / 12.2' November 18
2010 April 19 July 8 169" / 14.1' October 23
2011 April 19 July 16 242" / 20.2' November 22
2012 April 21 June 1 145" / 12.1' November 19
2013 March 21 May 24 140" / 11.7' December 18
2014 April 3 May 19 122" / 10.2' December 1
2015 March 31 May 3 91" / 7.6' November 8
2016 April 18 June 12 199" / 16.6' October 30
2017 April 4 July 26 243" / 20.3' November 10
2018 March 30 May 27 131" / 11' November 20
2019 April 18 June 22 238" / 19.8' November 29
2020 March 19 119" / 10'

Last updated: May 3, 2020

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Mailing Address:

PO Box 100
Mineral, CA 96063

Phone:

(530) 595-4480

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