Press release from California State Parks:
California State Parks will reopen the Mattole Road in Humboldt Redwoods State Park on Friday March 31st, at 4pm. A half-mile section of the road had been closed due to a landslide that occurred on January 17th. The closure was located 1.5 miles west of the juncture with Highway 101. Mattole Road runs west from the highway at the confluence of the south fork and main stem of the Eel River, then traverses through Humboldt Redwoods State Park.
California State Parks has been monitoring the slide and its impacts to the road as well as the surrounding landscape. The landslide was roughly 90 acres and extended north of Bull Creek to the top of the adjacent ridge. Multiple old-growth redwood trees toppled as a result of ground subsidence. The road was impassable due to large fissures and buckling of the asphalt.
Over the last several weeks, geoengineers have bored holes deep beneath the road surface and have employed inclinometers to assess the underlying geology. During that period the road has not moved appreciably. Parks will continue to monitor the road and will close it again if warranted.
The area where the road had been impacted is now resurfaced with gravel. Drivers should be aware that there is a 25 mph speed limit and to proceed with caution in the impacted areas due to the abrupt change from asphalt to gravel. The adjacent Rockefeller Loop Trail is currently closed and will be reopened once hazard trees have been assessed.