Big Bear Rockfall Crash: 5 Injured, Safety Tips for Mountain Roads

What Happened on Highway 18

On Friday evening, a massive boulder broke loose from the steep slope above Highway 18 and rolled onto the roadway near mile marker 44, west of Big Bear Lake. The falling rock struck or forced two vehicles to collide, resulting in a two-car crash.

Firefighters from San Bernardino County, along with Big Bear Lake and Arrowbear Lake fire departments, responded to the scene. They treated five people for minor injuries and transported four to local hospitals for further evaluation. The crash occurred during a period of heavy winter weather, which can weaken slopes and increase the risk of rockfalls on mountain highways.

Why Rockfalls Happen on Mountain Roads

Rockfalls are common on steep, mountainous roads like Highway 18, especially after heavy rain, snow, or freeze–thaw cycles. Water seeps into cracks in the rock, expands when it freezes, and gradually pries loose boulders over time.

Roads cut into hillsides can also destabilize slopes, and natural erosion or seismic activity can trigger rocks to break free without warning. In this case, the recent winter storm likely contributed to the slope failure that sent the boulder onto Highway 18.

How Drivers Can Stay Safe on Rockfall-Prone Roads

While you can’t control the weather or geology, there are practical steps drivers can take to reduce their risk on mountain roads where rockfalls are possible.

1. Slow down and increase following distance

Drive well below the posted speed limit on winding, mountainous roads, especially in bad weather. Slower speeds give you more time to react if a rock falls or another vehicle swerves.

Leave extra space between your vehicle and the one ahead so you can stop or maneuver safely if debris appears on the road. On Highway 18 and similar routes, many safety agencies recommend cutting your normal speed in half when conditions are wet, icy, or snowy.

2. Stay alert for warning signs

Watch for “Rockfall Area,” “Falling Rock,” or “Debris” warning signs along the highway. These indicate zones where rockfalls have happened before and are more likely to occur again.

Be especially cautious after heavy rain, snow, or rapid temperature changes, since these conditions increase the chance of loose rocks breaking free. If possible, avoid driving through known rockfall zones during or immediately after storms.

3. Choose your lane wisely

On two-lane mountain roads, the lane closer to the mountain (the inside lane) is often more exposed to falling rocks, while the outside lane (closer to the drop-off) may be safer from rockfall but riskier in other ways.​

If traffic allows, consider staying in the outside lane when passing through a rockfall zone, but always prioritize safe and legal driving over maintaining lane position. Never stop or park in a rockfall warning area unless absolutely necessary.

4. Keep your vehicle in good condition

Ensure your windshield, wipers, and headlights are in good working order so you can see clearly in rain, fog, or low-light conditions. A clear view of the road and slopes above helps you spot hazards earlier.

Ensure your tires have sufficient tread and are properly inflated, especially when driving in winter conditions near Big Bear or similar mountainous areas. Good traction improves control if you need to swerve or stop suddenly.

5. What to do if a rock falls or you’re in a crash

If a rock falls onto the road ahead, brake smoothly and steer to avoid it if possible, but do not make sudden, jerky movements that could cause a loss of control. If a collision is unavoidable, try to hit the rock at a shallow angle rather than head-on to reduce impact force.

If you are involved in a crash caused by falling rock or another vehicle, move to a safe location if possible, turn on hazard lights, and call 911. Take photos of the scene, the rock, and any damage, and exchange information with other drivers and witnesses.

What Authorities Are Doing to Prevent Rockfalls

Caltrans and other transportation agencies employ several engineering methods to mitigate rockfall risk on highways, such as Highway 18. These include rock bolts and anchors to secure loose blocks, shotcrete (sprayed concrete) to stabilize slopes, and high‑tensile wire mesh draped over rock faces to catch falling fragments.

They also install passive rockfall barriers and catch fences downslope to prevent or slow the movement of falling rocks before they reach the road. These systems are designed to absorb the energy of falling boulders and protect vehicles below.

When to Seek Legal Help After a Rockfall Crash

If you or a loved one is injured in a crash caused by a falling rock or debris on a public road, you may have rights under personal injury law. Depending on the circumstances, liability could involve the state (for road maintenance and slope safety), a construction company, or another driver.

If the crash resulted in medical bills, lost wages, or long‑term injuries, it’s wise to consult an experienced accident attorney who understands mountain road and premises liability cases. They can help investigate whether the road was properly maintained and whether warning signs or protective barriers were adequate.