Missoula Floods and Columbia River Gorge Geology with Jim O’Connor

Join the Lake Lewis Chapter of the Ice Age Floods Institute for a free public meeting and Missoula Floods lecture at the REACH Museum on Tuesday, November 3, 2026. Guest speaker Jim O’Connor of the U.S. Geological Survey in Portland, Oregon, will explore the Ice Age Floods and other geological stories of the Columbia River Gorge.

What can the Columbia River Gorge reveal about the Missoula Floods?

Beginning with the pioneering work of J Harlen Bretz and Ira Williams in 1915, geologists have followed evidence of the Missoula Floods through the Columbia River Gorge.

That research continues today as scientists investigate enduring and emerging questions: How many floods occurred? How large were they? When and where did they originate? How did they shape the landscape?

O’Connor will summarize the current understanding of the Missoula Floods in the Columbia River Gorge and share other geological stories being investigated by the USGS mapping group. The presentation concludes the Lake Lewis Chapter’s 2026 lecture theme tracing floodwaters from ancient Lake Missoula to the Pacific Ocean.

Event schedule

• Chapter Meeting: 6:30–7:00 p.m. PST
• Guest Lecture with Jim O’Connor: 7:00–8:00 p.m. PST

This event is free and open to the public. No registration is required.

The program will also be broadcast live. Instructions for joining online will be added to this page when available.

Questions may be emailed to lakelewis@iafi.org.