Skip to content
Basalt cliffs above Lake Lenore, July 2007
Elementary Inquiry

How did the Ice Age floods shape the land we live on today?

Introduction

Long before highways, cities, and farmland, powerful natural forces shaped the land we now call Washington. In this inquiry, students explore the dramatic Ice Age floods that swept across the Pacific Northwest thousands of years ago, and were some of the largest floods in Earth’s history. Using maps, images, and scientific explanations, students investigate how the floods carved out canyons, left behind giant rocks, and created the unique landscape of eastern Washington. This inquiry encourages students to see the land as a storyteller and to make connections between ancient events and the landforms they see today in their own communities.

Images

Giant ripple marks formed by powerful currents that flowed across Markle Pass near Camas Hot Springs, Montana, ca. 1976
Dry Falls, remnant of the world’s largest waterfall, July 2007
Grand Coulee Region exploratory group including J Harlen Bretz, Adrian (west of Soap Lake), ca. 1925
Floodwaters plucked boulders from these basalt cliffs near Soap Lake, July 2007
Glacial Landforms of the Puget Lowland

Maps

Distribution of the major lithospheric plates of the Earth
Map of channeled scablands drawn by J Harlen Bretz, 1925