Geological Hazards

Geological Hazards

• Rainfall-induced landslides are caused by heavy rain due to storms and southwest monsoons (habagat)
• Landslides result in the sliding down of soil, rocks, or mud from an elevated place, causing damage to houses, structures, and properties, and can even lead to loss of lives
• Negative economic effects of landslides include:
  • Cost to repair structures
  • Loss of property value
  • Disruption of transportation routes
  • Medical costs in the event of injury
  • Indirect costs such as lost timber and lost fish stocks
• Landslides can affect water availability, quantity, and quality

Warning Signs of Landslides

• Look for new areas of moisture
• Look for warping in your home
• Look for warping and movement in the surrounding area
• Notice unusual sounds
• Monitor changing water levels

Preparing for Landslides

• Follow proper land-use procedures
• Contact local officials about past landslides
• Consider building retaining or deflection walls
• Talk to an insurance agent if your area is at risk
• Make an emergency kit

Safety During a Landslide

• Keep yourself alert and awake
• Listen to a local news station for updates
• Evacuate if it is safe to do so
• Be cautious and alert while driving
• Move to a second story, if possible
• Move out of the path of the landslide as quickly as you can
• Avoid river valleys and other low areas
• Curl into a ball if you cannot escape

Safety After a Landslide

• Go to a public shelter
• Avoid the area where the landslide occurred
• Check for trapped and injured people
• Help neighbors who need special assistance
• Assess the area for damage and safety
• Replant the affected area
• Talk to a geotechnical expert

Sinkholes

• Form when water dissolves surface rocks
• Types of sinkholes:
  • Dissolution or solution sinkhole
  • Cover-subsidence sinkhole
  • Cover-collapse sinkhole

Causes of Sinkholes

• Soil erosion
• Underground caverns
• Leaking pipes and sewers
• Factors can compromise the underlying foundation over time, leading to sinkholes forming rapidly or gradually across a variety of terrains