Landslides can be caused by several factors, such as water saturation, slopes becoming steeper due to construction or erosion, freezing and thawing of land, shaking from earthquakes and their aftershocks, and volcanic eruptions. Gravity is the enemy during any kind of land movement.
Landslides can be slow or fast moving, depending on the area and weather related or man made factors.Landslides usually happen after periods of heavy water saturation. Flooding often occurs. In recently burned area, it does not take much water to start a landslide.
Mudslides, also known as mud flows or debris flows, are fast moving landslides. They typically occur after heavy rains or snow that melts quickly. They are usually associated with area with steeper terrain. Mudslides start out as shallow landslides, and with the help of gravity, gather debris and gain speed quickly. The consistency of a mudslide varies from watery mud to very thick mud to rocky mud depending on whatever is in its path. Depending on the terrain, separate mudslides can merge together, and pick up speed, gathering any debris in its path. It is not uncommon for mudslides to pick up rocks, boulders, trees, even cars. They more debris picked up along the way, the faster the flow, thus causing more havoc..When the flow hits flatter land, the debris spreads out, and can cause widespread destruction.Most people think of landslides or mudslides in hilly or mountainous area, especially after a heavy rain follows a fire. There is no vegetation to hold the water and mud and debris back. However, one example associated with volcanic activity is Mount Saint Helen in Washington state. This caused one of the largest debris flows on record. Another example happened in California along the Pacific Coast Highway. When a mudslide came to the bottom of a hillside, it wiped out the town of La Conchita and part of Pacific Coast Highway. Areas with a history of previous landslides, developed hillside areas, the bases of steep slops, areas where leach field septic systems are used, the bases of drainage channels (natural or man made), are all prone to landslides.Mudslides are a disaster that happens in all states. To find out how susceptible you are in your area, you can contact your local university's department of geology, your local or state geological society or department of natural resources. If you live in an area prone to slides, watch for storm water drainage on slopes near your home. Keep track of the places where water runoff comes together, or where the flow of water increases its flow over well covered slopes. Always check for signs of land movement on any hillside around your home, such as small landslides or trees that tilt and falling rocks.
Planning for a Landslide or Mudslide
► If you live in an area prone to mudslides, talk to your Insurance agent about insurance. through the National Flood Insurance Program, flood insurance may cover Debris flow from a slide.
► Have an Evacuation Plan. Discuss this plan along with your other Disaster Plans with all of the family. Everyone should know what to do in a Disaster situation, whether they are home or not. Discussions and planning helps to reduce the fear levels when responding to an emergency.
Have your Disaster Supplies and Emergency Kits ready!
Protect your Property Before a Storm
► You can contact private consulting company who specializes in earth movement for opinions and advice on problems and how to solve them. Look for Geo technical engineering, structural engineering, civil engineering. Trying to fix problems without professional advice could make the problem worse and cause more of a risk to you and your family and your property.
► The use of flexible pipe fittings can help you avoid water or gas leaks since they are less likely to break.
► Knowing what land issues are in your area, and what landslides have happened in the past, can help you to assess your risk for future problems and future danger.
► Watch for any activity around your property: any land movement or small slides, any pooling of water, or tilting trees or out structures.
During a storm
► Stay aware and watchful. Listen to the weather reports. Make sure you have your Disaster Supplies and Emergency Kits handy, both in the house and in the car should you have to evacuate. Remember the flashlights and portable radio.
► Short but intense bursts of rain, especially after longer periods of rain or damp weather, or when the ground is already saturated, can cause serious damage. If you can, consider leaving the area before a disaster happens. Be extremely cautious when driving in a bad storm or heavy downfall can be dangerous.
DO NOT CROSS ANY SWIFT MOVING WATER! You could be washed away in the current it creates. Avoid any landslide or mudslide areas or debris flows. Watch for falling rocks or boulders from hillsides.
► If you stay on the property, listen for unusual sounds, such as rushing water, or falling boulders or cracking tree limbs. These often precede a mudslide. Move to the highest floor of your home in case the mudslide is triggered and enters your house.
► If you live near a stream or river or flood channel, watch for sudden rises or falls in the water level. Also watch for clear water turning muddy or having more debris in it. If a change occurs, something is happening upstream. Be ready to evacuate. Since flowing water can move extremely fast, Get Out of the area Quickly.
With planning and proper actions, you can save the lives of you and your loved ones! Do not worry about your property. Things can be replaced, your Life cannot.
► Continue to monitor the weather information for evacuation warnings. Evacuate if necessary. If caught in a mudslide, move to the highest point you can safely. Curl up in a little ball to protect your head and face, and abdominal area from any debris strikes.
After a Storm
► Because there is danger from additional slides, stay away from the area.
► Without entering the direct slide area, you can heck for injured and trapped people near the slide. Listen for any sounds of people yelling or crying. Tell them to Stay Calm and quiet, and to breathe as normally as possible. When help arrives, you can send the rescuer workers to their locations.
► Listen to local radio or television stations for the latest weather reports and emergency information.
► Be aware and watchful. The main event which triggered the mudslide may trigger floods or more mudslides.
► Check your house and property for any structural damage. Check the foundation, chimney and surrounding land. Look for any broken utility lines or poles, and report any problems to your local utility companies as soon as possible.
If you see any damage, and it is safe to do so, leave the area.
► After the storm is over, replace any lost ground as soon as possible. Erosion caused by the loss of ground can lead to flash flooding in the event of another storm. Again, you can seek the advise of experts to help you evaluate the landslide hazards you may have and how to best solve those problems. They can help you design a plan to reduce or possibly prevent further slides and not create further hazards.
Help a neighbor who may require special assistance--infants, elderly people, and people with disabilities. Elderly people and people with disabilities may require additional assistance. People who care for them or who have large families may need additional assistance in emergency situations.