Approximately 8000 people a year are killed by landslides worldwide.Surviving a landslide or debris flow (mudslide) is dependent on you being awake at the time of its occurrence, and aware of what is happening. Should you find yourself in the midst of a landslide, there are things that you can do to increase your chances of survival, as outlined in the following steps.
Staying alert for the possibility
Understand what constitutes a landslide. In a landslide, masses of rock, earth, or debris move down a slope. Landslides may be small or large, slow or rapid. They are activated by storms, earthquakes, volcanic eruptions, ﬁres, and human modification of land.
- Debris and mud ﬂows are rivers of rock, earth, and other debris saturated with water. They develop when water rapidly accumulates in the ground, during heavy rainfall or rapid snow melt, changing the earth into a ﬂowing river of mud or “slurry.”
- They can ﬂow rapidly, striking with little or no warning at avalanche speeds. They can travel several miles from their source, growing in size as they pick up trees, boulders, cars, and other materials.
Be aware of your environs at all times. Whether you live in an area prone to landslides, or you are traveling in such an area, it is important to note the local geological features and be aware of the potential for a landslide. Things to note around you include:
- Changes to the normal activity on your landscape, such as patterns of storm-water drainage on slopes (especially the places where runoff water converges) land movement, small slides, ﬂows, or progressively leaning trees.
- Doors or windows stick or jam for the first time.
- New cracks appear in plaster, tile, brick, or foundations.
- Outside walls, walks, or stairs begin pulling away from the building.
- Slowly developing, widening cracks appear on the ground or on paved areas such as streets or driveways.
- Underground utility lines break.
- Bulging ground appears at the base of a slope.
- Water breaks through the ground surface in new locations.
- Fences, retaining walls, utility poles, or trees tilt or move.
- The ground slopes downward in one direction and may begin shifting in that direction under your feet.
- Unusual sounds, such as trees cracking or boulders knocking together, might indicate moving debris. A trickle of flowing or falling mud or debris may precede larger landslides. Moving debris can flow quickly and sometimes without warning.
- A faint rumbling sound that increases in volume is noticeable as the landslide nears.
- Collapsed pavement, mud, fallen rocks, and other indications of possible debris flow can be seen when driving (embankments along roadsides are particularly susceptible to landslides).
Stay alert and awake. If there are any of the above indicators in your area, do not go to sleep. Many debris-flow fatalities occur when people are sleeping. Listen to a weather radio or a portable, battery-powered radio or television, for warnings of intense rainfall.
- Be aware that intense, short bursts of rain may be particularly dangerous, especially after longer periods of heavy rainfall and damp weather.
Consider leaving. If you are in areas susceptible to landslides and debris flows, consider leaving if it is safe to do so.
- Shift vulnerable people immediately to safer areas, as a precaution.
During a landslide
If you remain or are caught suddenly at home, move to a second story if possible. Staying out of the path of a landslide or debris flow saves lives.
If you are near a stream or channel, be alert for any sudden increase or decrease in water flow and for a change from clear to muddy water. Such changes may indicate landslide activity upstream, so be prepared to move quickly. Don’t delay! Save yourself, not your belongings.
Be especially alert if you are driving. Embankments along roadsides are particularly susceptible to landslides. Watch the road for collapsed pavement, mud, fallen rocks, and other indications of possible debris flows.
- A landslide can completely engulf a car on a road that is in its path.
Whenever you are in the path of a landslide or debris flow, move away as quickly as possible. If escape is not possible, curl into a tight ball and protect your head with your hands or a helmet.
After a landslide
he danger is not over after a landslide has passed through. It may not be the only landslide, and there will be a lot of damage left in the wake of the landslide that can present hazards. There are a number of things that you should do to minimize the danger.
Stay away from the slide area. There may be danger of additional slides.
Check for injured and trapped persons near the slide, without entering the direct slide area. Direct rescuers to their locations.
Watch for associated dangers such as broken electrical, water, gas, and sewage lines and damaged roadways and railways.
Return home with care. If you left your property or home to go to safer ground, be very careful when you return. Things to consider include:
- Understanding that returning home can be both physically and mentally challenging. Above all, use caution.
- Keep a battery-powered radio with you so you can listen for emergency updates and news reports.
- Use a battery-powered ﬂash light to inspect a damaged home. The ﬂashlight should be turned on outside before entering—the battery may produce a spark that could ignite leaking gas, if present.
- Watch out for animals, especially venomous snakes. Use a stick to poke through debris.
- Use the phone only to report life-threatening emergencies.
- Stay off the streets. If you must go out, watch for fallen objects, downed electric wires, and weakened walls, bridges, roads, and sidewalks.
Walk carefully around the outside and check for loose power lines, gas leaks, and structural damage. If you have any doubts about safety, have your residence inspected by a qualified building inspector or structural engineer before entering.
Do not enter your home if:
- You smell gas.
- Flood water remain around the building.
- Your home was damaged by ﬁre and the authorities have not declared it safe.
Consider long-term repairs. To avert the future possibility of a dangerous landslide, there are some additional things that can help:
- Replant damaged ground as soon as possible since erosion caused by loss of ground cover can lead to ﬂash ﬂooding and additional landslides in the near future.
- Seek advice from a geo-technical expert for evaluating landslide hazards or designing corrective techniques to reduce landslide risk.
- Landslides are extremely dangerous, so it is far better to evacuate immediately if you suspect imminent danger than to ponder the potential.
Things You’ll Need
- Safe area to escape to
- Radio or media access to remain informed