DRRR Reviewer (Rainfall)

• Landslide (Landslip)


  A ground movement on a sloping terrain, where gravity induces the land to move downward. The hazard of landslide can be induced further or aggravated by rain.
• Areas prone to landslides

  • Steep slope
  • Dense population
  • Denuded ground
• Sinkhole


  Depressions or holes on the ground that resulted from the collapse of the surface layer of the soil, occurring in areas where the soil foundation is made of soft minerals and rocks (limestone, salt beds, or any acidic rock)
• Causes of sinkhole formation

  • Earthquake
  • Volcanic activities
  • Construction and industrial activities
• Signs of impending landslides or sinkholes

  • Springs, water seepage, or water saturated grounds in areas that are not typically wet
  • Soil that loosens and moves away from foundations
  • New cracks or unusual bulges on cemented ground or walls
  • Underground utility lines that are broken due to vibrations or tremors from the surface of the ground
  • Buildings, poles, walls, and fences that are leaning
  • Sudden rapid flow of creek waters carrying more silted water
  • For sinkholes, signs of an imminent danger in groundwater that does not provide the same amount and quality as before or has become cloudy, acidic, silted or soiled
  • Sign post or poles that are suddenly leaning, slumping, sagging, slanting, or bent
  • Ponds that have recently formed or puddles that grow or have never disappeared
• Scientific tools for assessing landslides


  • Abney level or a laser rangefinder equipped with a tiltmeter to measure slope angle, soil compaction, and soil strength
• Scientific tools for assessing sinkholes


  • Ground penetrating radar to detect the type of materials underneath the soil
• Areas that have the highest vulnerability to rainfall-induced geologic hazards have already been identified by the MGB of the Department of Environment and Natural Resources (DENR) through their Geohazard Mapping and Assessment Program.
• Precautionary measures in case of a landslide


  • Plant more trees, grasses, and other vegetation to prevent erosion and for compaction of soil
  • Build channels for diversion of mudflow or debris flow to direct the flow away from your property
  • Do not build your house on or near steep slopes, mountain edges, drainages, or natural erosion valleys
• Precautionary measures before a landslide


  • Be familiar with your surroundings
  • Avoid open storm-water drainage and runoff as these areas are likely to receive debris
  • Be updated on news regarding the condition of your area
  • Learn and participate in emergency response and evacuation plans for your community
• Precautionary measures during a landslide


  • Be attentive to unusual sounds such as cracking objects, moving debris, and rolling boulders
  • Stay away from the path of debris
  • Stay on an elevated and sturdy area
  • If escape is not possible, curl into a tight ball and protect your head. Find a structure that can serve to protect you from the flow of debris
• Precautionary measures after a landslide


  • Avoid the slide area
  • Listen for the latest emergency information
  • If the landslide is caused by rainfall, watch out for flooding as it will follow the same path
  • Check for injured or trapped people near the slide, and for damaged structures and other potential hazard