Rockfall Mitigation Solutions for Washington

Access Limited deploys a full range of engineered rockfall mitigation systems across Washington. Each solution is selected based on site-specific conditions — rock type, slope geometry, catchment requirements, and traffic exposure along corridors like I-90 over Snoqualmie Pass, SR-14 along the Columbia Gorge, US-2 over Stevens Pass, and SR-20 through the North Cascades.

Wire Mesh and Draped Mesh Systems

Wire mesh and draped mesh installations control rockfall at the source by confining loose material on the slope face. In Washington, these systems are engineered for the specific rock mass conditions found along WSDOT corridors.

• Draped mesh — Anchored at the slope crest and allowed to drape over the face, guiding falling rock to a controlled collection zone at the toe
• Pinned mesh — Secured directly to the rock face with pattern-bolted anchors, preventing movement of individual blocks and slabs
• High-tensile steel mesh — Engineered for high-energy rockfall zones where standard mesh cannot absorb the impact loads

Flexible Rockfall Barriers and Catch Fences

Flexible rockfall barriers intercept falling rock before it reaches the roadway. Access Limited sizes barrier systems based on block size, fall height, and energy calculations specific to each Washington corridor.

• Flexible barriers — Energy-absorbing post-and-cable systems rated from 100 kJ to over 5,000 kJ, placed in the rockfall trajectory zone
• Catch fences — Lower-profile containment fencing for moderate-energy rockfall along ditches and benches
• Hybrid systems — Combined barrier-and-ditch configurations engineered for corridors with limited catchment area

Rock Bolting and Anchor Systems

Rock bolting stabilizes individual blocks and fractured zones in place — preventing rockfall before it initiates. Access Limited's Spyder Drill Rigs install bolt patterns on near-vertical Washington rock faces that conventional drill rigs cannot access.

• Fully grouted rock bolts — Passive reinforcement anchored through the failure plane into competent rock
• Tensioned rock anchors — Active reinforcement applying compressive load across open joints and fracture systems
• Pattern bolting — Systematic bolt grids securing entire slope faces in highly fractured rock

Rockfall Attenuator Systems

Attenuator systems reduce rockfall energy by guiding falling rock through successive curtains of steel mesh — slowing each block before it reaches the roadway below. These are engineered for Washington corridors with long, steep fall paths.

• Curtain attenuators — Suspended mesh panels that absorb energy progressively down the slope
• Hybrid attenuator-barrier systems — Combined energy reduction and final containment for high-exposure corridors

Rock Scaling Operations

Scaling removes loose and unstable rock from slope faces before it falls — the most direct form of rockfall hazard reduction. Access Limited performs mechanical and manual scaling across Washington using Spider Excavators and rope-access crews.

• Mechanical scaling — Spider Excavators remove loose rock from steep faces with hydraulic breakers and bucket work
• Manual scaling — Rope-access technicians hand-scale individual blocks and wedges on exposed faces
• Controlled trim blasting — Precision blasting to remove large unstable masses where mechanical methods are insufficient

Every rockfall mitigation solution Access Limited installs in Washington is engineered for the specific conditions of the site — not selected from a generic catalog. Access Limited's Pacific Northwest presence — headquartered in nearby Forest Grove, Oregon — enables rapid deployment to any WSDOT corridor across the Cascades.