Meaning: water and mud, usually volcanic ash, that rushes down the side of a volcano sweeping over anything in its path.

Fast Facts:

  • lahars can extend over long distances
  • their water can be hot, being heated by volcanic activity
  • the water can consist of melted snow and ice
  • lahars have killed many people
  • More than 23,000 people were killed in Armero, Colombia, in a mudflow that started 50km away (1985)
  • As mudflows start they can carry along boulders, trees and construction materials causing widespread damage
  • In Japan large dams have been built to slow down mudflows give people time to escape the danger