Iliamna and Redoubt are both active volcanoes within Lake Clark National Park. Gases are frequently seen venting near the summit of Iliamna, but there are no documented reports of recent eruptions, according to the USGS.
Redoubt Volcano's recent eruptive periods include its awakening on December 14, 1989, dumping varying amounts of ash primarily north and west of the volcano and lightly dusting Anchorage and Kenai. Periodic eruptions continued throughout the week before Christmas, disrupting holiday air traffic and nearly causing the crash of a passenger jet. The jet unknowingly flew through a Redoubt ash cloud. The ash clogged the jet's engines and the jet plummeted about 10,000 feet before the pilot was able to restart the engines and land safely in Anchorage. Redoubt experienced 23 explosive events before its culminating eruption April 21, 1990.
Redoubt entered into another eruptive period in March of 2009 with several explosive events spreading ash north, east and south of the volcano. Hot ash and pyroclastic flows melted significant parts of the glacier ice mantling the volcano sending numerous lahars (mudflows) down the Drift River. This eruptive period concluded in April when the extrusion of a massive lava dome plugged the volcano's vent. Seismic activity in the vicinity of the lava dome is being observed closely by the Alaska Volcano Observatory. Instability of the lava dome has the potential to trigger an eruption at some future date.
Both Iliamna and Redoubt are among the volcanoes continuously monitored by the Alaska Volcano Observatory (AVO). For direct links to AVO's pages on the park's volcanoes click on their names below:
Alaska Volcano Observatory: Iliamna Volcano
Alaska Volcano Observatory: Redoubt Volcano
Did You Know?
Lake Clark is 1056 feet deep and covers 128 square miles. Thousands of years ago, the lake (and nearby Lake Iliamna) may have been open to salt water before being closed off by glacial outwash deposits.