Slope or Hillside Failure: What to Do in the First 72 Hours
If a slope, retaining wall or hillside road starts to move, get people away from it and call 911 if anyone is in danger. Then stop water from reaching the area, document what you see with dated photos, call your local building and safety office and your insurance, and bring in a geotechnical engineer and an experienced civil contractor to stabilize it.
When a hillside starts to move, people want to act fast. The right first moves protect people, limit the damage and set up a permanent fix. Here is the order we recommend.
Hour 0: People first
- Keep everyone away from the moving area, both above and below it.
- Call 911 if anyone is hurt or a structure or road is in danger.
- If you smell gas or see damaged power lines, leave the area and call the utility.
Hours 1 to 24: Stop the water
Water is behind most slope failures. Shut off irrigation on and above the slope. Redirect roof drains and downspouts away from it. If it is raining, plastic sheeting placed and anchored from a safe position can keep more water out of cracks. Don't climb onto a moving slope to do it.
Hours 1 to 24: Document everything
- Take dated photos and videos from safe spots, the same spots each day.
- Mark crack ends with paint or stakes so you can see whether they grow.
- Note any water coming out of the slope and any new cracks in walls, driveways or floors.
Hours 24 to 48: Make the calls
- Your local building and safety office, which may inspect and post the property.
- Your insurance carrier, with your photos.
- A geotechnical engineer, who evaluates the slope and designs the permanent repair.
- An experienced civil contractor for emergency stabilization under the engineer's direction.
Hours 48 to 72: Stabilize, then plan the fix
Emergency work buys time: controlling water, protecting the slope from rain and, where the engineer calls for it, temporary measures. The permanent repair, which may include drainage, retaining walls or caissons, is designed by the engineer and built to those plans.
What not to do
- Don't pile soil or debris at the top of the slope.
- Don't dig at the toe of the slope.
- Don't wait for the next storm to see what happens.
How we help
We do emergency hillside stabilization, drainage, retaining walls and caissons across Greater Los Angeles, working with your geotechnical engineer. Call (800) 606-3880.
Sources
JFPEC field practice on emergency hillside work. Design of permanent repairs stays with the geotechnical engineer and Engineer of Record.