Effects of the eruption Primary effects Secondary effects Nuée ardente (hot ash and gas) destroyed forests and logging camps. 63 people were killed, mainly by poisonous gases. Lahars (mudflows of ash and water) covered an extensive area surrounding the volcano. Ash blocked rivers destroying popular fishing sites and causing flooding. This in turn destroyed crops and livestock. Flooding destroyed communications such as road and railway bridges. Sediment carried downstream ruined barge transport on the Columbia River. Social Economic Environmental • 56 people were killed • 200 homes destroyed by Lahars • 185 miles of road and 15 miles of railway destroyed • 27 bridges • Several logging camps destroyed • 12% of total crop destroyed • Estimated loss of $800 million in Washington state • $250 million cost of cleanup operation • Small mammals in the area wiped out. • km of forest destroyed • Ecosystems destroyed by lahars • 7,000 big game animals destroyed • Flood risks increased due to increase in sediment
