The recent wildfires across the west side of the country have increased the danger and rate of mudslides, landslides, and debris flows. We have included advice and information on how to prepare before, react during, and recover after one of these natural disasters.
Recognize the causes of landslides, mudslides and debris flows
Landslides occur in every US state. They are typically caused by earthquakes, storms, wildfires, and human actions upon the environment. A landslide or mudslide is a rapidly flowing river of rock, dirt and debris that develops when water accumulates in the ground due to rainfall or snow melting. The recent wildfires in the western US have caused frequent landslides.
“Wildland fires are inevitable in the western United States. Expansion of human development into forested areas has created a situation where wildfires can adversely affect lives and property, as can the flooding and landslides that occur in the aftermath of the fires.” — USGS.gov
Wildfires cause landslides because the forest canopy is damaged. This leads to more runoff. The runoff then causes destructive debris to flow rapidly, damaging land and property. Wildfires also put structures at a higher risk of flooding.
“Post-fire landslide hazards include fast-moving, highly destructive debris flows that can occur in the years immediately after wildfires in response to high intensity rainfall events, and those flows that are generated over longer time periods accompanied by root decay and loss of soil strength.” — USGS.gov
These landslides are more dangerous because they can happen suddenly and without much warning.
Warning signs of landslides or mudslides
Landslides often occur frequently in the years following wildfires. Once the forest canopy, plants, and soil have been damaged by these fires, water from rainfall or snow melting is not absorbed as efficiently, runoff increases, and mudslides and landslides occur. If a wildfire or other landscape change has occurred recently, you should prepare for the possibility of a landslide.
More warning signs include:
- Cracks forming in foundations, walls, and ceilings
- Doors and windows are more difficult to open/close
- Driveways and walkways crack
- Utility lines underground are damaged
- Ground is broken/bulging with new water
- Fences and trees are tilting or displaced
- You can hear rumbling
- You can hear trees cracking
After a wildfire, watch out for other hazards like flooding and rockfalls. You can sign up for emergency alerts to make sure you’re aware of any threats.
How to prepare before a landslide or mudslide
If you’re in a region prone to wildfires and/or landslides, you should prepare now. Start by creating an emergency kit as well as a family plan.
Your emergency kit should enable you to survive for potentially several days. This means it should contain food, water, medical supplies, and anything else necessary to your survival.
Emergency Kit Checklist:
- 1 gallon of water/person/day for a minimum of 3 days
- 3 day supply of non-perishable food
- Infant supplies
- Pet supplies
- Battery-powered radio / NOAA Weather Radio + extra batteries
- Medical supplies / First aid kit / Prescriptions
- Masks to filter air & prevent the spread of COVID-19
- Hand sanitizer
- Disinfecting wipes
- Plastic sheets to create a shelter
- Sleeping bags
- Clothing & shoes
- Duct tape
- Tools (including a wrench, utensils and can opener)
- Charged phones + back-up portable charger
- Important documents (insurance, IDs)
- TrapBags and/or other barrier supplies to protect your property
When making your family plan, make sure everyone knows where to go/meet, and how to protect themselves during the COVID-19 pandemic. Have everyone sign up for emergency alerts.
Ready.gov recommends: “the Emergency Alert System (EAS) and National Oceanic and Atmospheric Administration (NOAA) Weather Radio also provide emergency alerts. Sign up for email updates and follow the latest guidelines about coronavirus from the Centers for Disease Control and Prevention (CDC) and your local authorities to prevent the spread of COVID-19. Leave if you have been told to evacuate or you feel it is unsafe to remain in your home. Text SHELTER + your ZIP code to 43362 (4FEMA) to find the nearest shelter in your area (example: shelter 12345).”
Make sure to have an assessment of your property conducted by a certified professional. After your assessment, implement necessary preventative measures. TrapBags can help protect your property against landslide and mudslide damage following wildfires. TrapBags are an affordable, sustainable, and efficient barrier system alternative to sandbags.
What to do during a mudslide or landslide:
- Tune In. During a landslide, make sure to tune into local news stations on your battery-powered radio to stay informed. Make sure to adhere to ALL evacuation notices and follow any instructions given.
- Stay Healthy. If you need to evacuate and must shelter with people from other households, make sure to wear a mask and maintain social distance to prevent the spread of COVID-19.
- Stay Awake. During weather events which could lead to landslides, make sure to stay awake and pay attention to the situation. Many deaths have occured when people were sleeping during the event.
- Evacuate Quickly. If debris is already flowing, it’s too late to evacuate. It’s very dangerous to attempt to cross the flow. If you become stuck in or near the flow, try to navigate to higher ground as fast as you’re able.
How do TrapBags work to protect from mudslides or debris flows?
A well positioned TrapBag® barrier system will redirect these mountain floods and mudslides to avoid unnecessary damage to property and residents that would otherwise be in danger. TrapBags® can redirect debris flows and protect infrastructure. By installing TrapBags® around your home you create a barrier that will redirect the mudflow away from or around your home, preventing the damage that would be caused otherwise. Having TrapBags® in place will save properties and lives. TrapBags® can be used for mudslide protection by using them to stabilize the unstable slope, or in many situations you may use the barriers to redirect a mudslide (mudflow) to change its path and prevent it from destroying properties.
What to do after a landslide or mudslide
After the landslide, make sure to stay away from the area since another slide could occur. Keep an eye out for flooding, which can also happen after wildfires.
- Make sure no one has been injured and contact rescuers to help.
- Report damages including any potential hazards (like utility lines).
- Make sure structures have been professionally inspected.
- Try to replace any vegetation loss to prevent further erosion and damage.
- Isolate if you have been exposed to COVID-19 after sheltering with other households.
There can be a lot of damage following a landslide or mudslide including damage to roadways, structures, and the environment. Cleaning up after a landslide can be difficult and potentially dangerous. The debris can contain hazardous materials such as:
- Bacterial contamination
- Hazardous chemicals
Check with your county for safety information regarding disaster clean up before attempting to clean up on your own.
How do I remove TrapBags after a mudslide, and can TrapBags be reused?
To remove the TrapBags that were used, you must cut open each cell on the vertical side from the bottom of the bag up towards the top. This will allow the fill material to escape. Then you remove the plastic with a thumb and bucket on a mini-excavator. TrapBags are not reusable. New TrapBags should be installed if ever needed.