Mount Redoubt as seen looking west along a Kenai Spur Highway side street in Soldotna. This very active volcano has erupted five times since 1966. During the 1966 eruption, melting ice produced a jokulhlaup. (A Jokulhlaup is a glacial outburst caused by melt water from a subglacial volcano -
not surprisingly it is an Icelandic term). The four eruptions since 1966 have been moderate to large. The most recent eruptions were in 1989-1990. The eruptions caused considerable disruption to air traffic. Debris flows in Drift River valley threatened an oil tanker terminal. Damage and loss of revenue from ash and debris flows totaled about $160 million, making the 1989-1990 eruption the second most costly in the United States history.