Bumpass Hell Trail and Boardwalk Rehabilitation

Left: the newly reconstructed boardwalk in Bumpass Hell basin; Right: New stone retaining walls and gravel fill on the trail.

 

A Multi-Year Project

Lassen Volcanic began a multi-year project to rehabilitate the Bumpass Hell Trail and boardwalk in 2018. 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 Rehabilitation Project. Click on the map to view a larger version of the map and the current project handout.

Project Objectives

Improve 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.

Reconstruct 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.

Add 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.

Enhance 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.

 

2018 Accomplishments

The reconstructed boardwalk is complete and open to hikers from the Kings Creek Picnic Area Trailhead (via Cold Boiling Lake). A single walkway passes through the basin to a turnaround point just north of the Pyrite Pool. The new boardwalk is constructed of recycled, plastic lumber reinforced with fiberglass rods. This material is expected to better withstand the acidic gases and other caustic elements in this active hydrothermal area. The new beige planks blend into the basin and float just above the ground, reducing the visual impact on the landscape.

Trail improvements are 50 percent complete. The park trail crew constructed stone retaining structures along trail edges to create erosion control and restore the trail’s original, mild grade of six percent. Where necessary, crews cut and placed additional rock to fill dips and water passageways and restore the original trail width of four feet. Crews then used trail carts to transport gravel to fill in the eroded areas and cover tripping hazards such as rocks and tree roots.

2019 Objectives

Park staff will resume trail improvement efforts on the second half of the trail as soon as it is clear of snow. Trail crew anticipates completion one month after work begins. As with the normal summer trail opening of this high elevation trail, this date is largely dependent on winter snowpack and spring conditions. Due to heavy winter snowfall, the trail may not be accessible to begin work until well into August. Once trail improvement work is complete and the trail is reopened to the basin, crew members will begin work on the remaining project objectives including:

• Restoring a 0.2-mile historic trail to provide a second route between the basin overlook and the basin.
• Enhancing overlooks along the trail and within and above the basin to improve the visitor experience.
• Rehabilitating five impacted areas adjacent to the trail.