Bumpass Hell Trail and Boardwalk Rehabilitation

Visitors on a boardwalk in Bumpass Hell hydrothermal area
Hikers on the boardwalk in Bumpass Hell basin

Bumpass Hell Trail and Boardwalk Closed in 2018 for Rehabilitation

View information about the closure including the closure map and recommended alternatives to visiting Bumpass Hell here.
A man walks on a wooden boardwalk above a steaming hydrothermal area.
A boardwalk provides a close-up view of dramatic hydrothermal features.

A Multi-Year Project

In 2018, the NPS will begin a multi-year project to rehabilitate the Bumpass Hell Trail and boardwalk. The purpose of project is to ease maintenance for the Bumpass Hell Trail and boardwalk, while preserving natural and historic resources, improving interpretive opportunities, and accommodating high visitor use to and within the Bumpass Hell Basin.

The hottest and most vigorous hydrothermal features in Lassen Volcanic National Park are at Bumpass Hell. A three-mile round-trip trail―one of the most popular in the park―provides access to the Bumpass Hell basin. Within the basin, a boardwalk traverses a portion of the hydrothermal area and additional trails offer access to the southern portion of the basin and connect to additional area trails. While Bumpass Hell is a popular destination for park visitors, it is also a dynamic geologic area in which the only predictable element is change.
Map of Bumpass Hell trail and boardwalk identifying areas and actions for rehabilitation project
Map of Bumpass Hell Trail and Boardwalk Rehabilitation Project. Click on the map to view a larger version of the map and the current project handout.

Bumpass Hell Rehabilitation Project Underway

Lassen Trail Crew has begun work to rehabilitate the Bumpass Hell Trail and boardwalk following the completion of the Environmental Assessment (EA) process. The final EA identifies rehabilitation actions identified in Alternative 2 with some minor modifications. View the Environmental Assessment at parkplanning.nps.gov.

Improving the Historic Trail

The original Bumpass Hell trail was constructed in 1935 by the Civilian Conservation Corps. Trail improvements will both preserve the historic character of the trail and improve visitor access. Trail improvements between the trailhead and basin overlook include:

  • Restore original trail width of four feet to make passing easier and eliminate pinch points.
  • Rebuild stone retaining walls along the length of the trail.
  • Improve trail tread by creating erosion control systems and restore a mild grade of six percent to facilitate use by visitors with mobility impairments.
  • Rehabilitate five impacted areas adjacent to the trail.

Reconstructing the Basin Boardwalk

  • The boardwalk, which provides access to a portion of the hydrothermal area, will be reconstructed to maintain an up-close, full-sensory experience in the Bumpass Hell Basin. A single walkway will connect the Bumpass Hell Trail to a turnaround point near the Pyrite Pool.
  • Recycled, plastic lumber reinforced with fiberglass rods will provide a solid structure that will blend into the basin and withstand the acidic gases and other caustic elements in this active hydrothermal area.

Adding a Second Trail into the Basin

A 0.2-mile historic trail will be restored to provide a second route between the basin overlook and the basin. Because this trail is less steep and melts out from snow faster than the existing trail, its addition should improve access in the spring. The new trail will include a close-up look at shallow, vigorously boiling pools of clear water known as frypans and previously inaccessible wetlands. A newly constructed bridge and short section of boardwalk along the trail will allow safe access and protecting these fragile environments.

Enhancing Overlooks

Overlooks along the trail and both within and above the basin will be expanded or enhanced to improve the visitor experience. Overlook improvements include:

  • Improve the view of the eroded rim of Brokeoff Volcano by reconfiguring the gathering space, adding seating, and rehabilitating the interpretive wayside.
  • Enhance the Bumpass Hell Basin overlook by raising and leveling the area and removing a few small trees not present historically to provide a better view, adding additional seating, updating the interpretive wayside, and adding removable spotting scopes.
  • Enhance the inner basin overlook by adding low-profile interpretive signs and additional seating.
  • Improve the informal outer basin overlook located above the Pyrite Pool with interpretive waysides.

Last updated: August 23, 2018

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Mineral, CA 96063


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