Spring Road Clearing

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 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

 

• 

  How Park Road Crews Clear Snow From Lassen Volcanic National Park Highway

  See how park road crews clear snow from the park highway in a two-month long process each spring.

  Duration:

  4 minutes, 27 seconds

 

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'