Wallula Gap: An Ice Age Floods Lecture with George Last
Join the Lake Lewis Chapter of the Ice Age Floods Institute for a free public meeting and guest lecture featuring George Last on Tuesday, September 1, 2026, at the REACH Museum.
How did Wallula Gap shape the Ice Age Floods?
George Last will explore the geology and history of Wallula Gap, an important local feature in the path of the Ice Age Floods. The presentation continues the chapter’s 2026 lecture series tracing floodwaters from ancient Lake Missoula to the Pacific Ocean.
Learn how Wallula Gap restricted the flow of massive floodwaters, causing water to back up across the Pasco Basin and temporarily form Lake Lewis.
Event Schedule
- Chapter Meeting: 6:30–7:00 p.m. PDT
- Guest Lecture with George Last: 7:00–8:00 p.m. PDT
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.