More Big Skies, Silos, and Geology - Eastern Washington 2026 (Part 2)

We continue our June 2026 road trip into central eastern Washington. 

Heading north into north central part of the state, the terrain becomes more hilly. Occasional coulees (water-scored gullies) downcut into the underlying basalt. It is fascinating geology.

Odessa is a city in wheat country. We saw some German influence. Here in central Washington? I read later that some 80 percent of the immigrants in the late 1800s were Germans from Russia. 

Farm house near Odessa

Grand Coulee (the city) is located next to Lake Roosevelt, which is the Columbia River upstream of the huge Grand Coulee dam. Basalt walls loom above the city - it has a nice physical situation. The town itself is not too exciting. But it has an excellent coffee shop, the appropriately named Voltage Coffee House on Spokane Way. After driving through central Washington, it was time to stop for some volts. An old shed was next door.   

 

Head southwest along the spectacular Coulee Boulevard. It. runs along the west edge of the coulee (canyon), with basalt cliffs looming above you to the east. Banks Lake glistens blue to the west. But where to stay? Ah, ha, the Ala Cozy Motel in Coulee City. (The names are confusing; this is a different city than Grand Coulee.) Dinner at Couleegan's Bar & Grill was this incredible broasted chicken. Wow, enough chicken for a week of road trip!

 

 Coulee City is pretty quiet. But it had some interesting silos on the west edge of town.

 

 

Continue southwest to the Sun Lakes-Dry Falls State Park. Here, rock outcrops and lakes are more examples of the scouring and downcutting from the immense floods that coursed across this land when glacial Lake Missoula burst through its ice dam.

 

Fractured basalt boulder near Umatilla Rock, Sun Lakes-Dry Falls State Park

After hiking in Dry Falls, continue southwest to Quincy for a visit to the Ancient Lakes. There are several easy hikes, and you can camp here (but beware, the water in the lakes is farm runoff, so not drinkable).

Ancient Lakes from Upper Trailhead (Samsung phone digital file)

Hexagonal basalt and waterfall below the Upper Trailhead

Fractured basalt boulder near Lower Trailhead (Kodak T400CN film, 50mm ƒ/1.8 Canon lens) 

We reluctantly headed west towards Ellensburg. This is a nice college town. After hundreds of miles in eastern Washington, we were hungry. Dear readers, you know where this is going. We went to Smokey's on Pearl Street. Ahhhh....

Carnivore's delight - Smokey's on Pearl Street

This ends out June 2026 road trip in eastern Washington. There is more to explore. Time to return with a 4×5" camera.

I took the square pictures with a Rolleiflex 3.5E twin-lens camera with 75mm ƒ/3.5 Xenotar lens (5-element version) on Kodak Ektar 100 film. Glazer's Camera in Seattle, Washington, developed the film and scanned it with a Noritsu system. 

 

Rolleiflex 3.5E with 75mm ƒ/3.5 Schneider Xenotar taking lens

2025 E. Washington Road Trip 03 - Palouse Falls and Washtucna

 

Palouse Falls State Park Heritage Site

Palouse Falls is a geologic wonder in east central Washington. The rock here is part of the Columbia River Basalt Group, which covers over 81,000 square miles of the earth's surface in eastern Oregon, eastern Washington, western Idaho, and part of northern Nevada. Most of the basalt erupted between 14 and 17 million years ago, or the middle-late Miocene epoch. We do not need to delve deeper into the volcanic history of the region, but consider that you see these remarkable basalt outcrops in many parts of the state east of the Cascades. 

Map of the Columbia River Basalt Group, from the Volcano Hazards Program, US Geological Survey

The spectacular canyon and the waterfall at the state park are a result of immense floods that burst from Glacial Lake Missoula. Near the end of the last continental glacial era, about 15,000 years ago, a lobe of ice blocked the drainage of what is now the Clark Fork River. The water that backed up created Glacial Lake Missoula, a major body of water that may have included as much volume as the combined present Lakes Erie and Ontario. As the water level rose, pressure against the ice dam increased and caused the ice to float. The dam failed and a mass of water rushed westwards (see the figure below). Peak flow may have been as high as 386 million cubic feet per second (cfs). As a comparison, the flow of the Mississippi River at Old River Control during the record 2011 flood was 2 million cfs.

Floodwaters rushed across east central Washington towards the Columbia River valley and on to the Pacific. The waters carved an immense network of channels, canyons, and valleys, creating what we now call the Channeled Scablands. These included Grand Coulee, where the dam is now located, Dry Falls, and Palouse Falls. Flood waters even reached south deep into the Willamette Valley of Oregon, where they deposited masses of sediment. Geologists now estimated that there were at least 40 of these pulses of water that occurred over a period of about 2,500 years.

Consider the time scale. The earth is about 4.5 to 5 billion years old. The Missoula Floods occurred about 15,000 years ago, only a is a tiny fraction of earth's history. Humans may have come to North America during the last glacial maximum between 21,000 and 23,000 years ago (based on footprints found at White sands National Park). Therefore, predecessors of our present native Americans saw these floods. 

The Washington Department of Natural Resources has an excellent interactive presentation of Washington's Ice Age floods. 

Areas affected by floods (teal color), from the

 Montana Natural History Center, Glacial Lake Missoula Chapter.

 Note the ice lobe that extended south into the Puget Lowlands.

Palouse Falls from the visitor's center (Samsung phone digital file)

These amazing columns of basalt show lava flows of different ages. When the basalt cools quickly, it forms hexagonal columnar formations. Devil's Tower in Wyoming (where the UFOs land) and the Giant's Causeway in Northern Ireland are other well-known examples. A Wikipedia article lists other examples around the world.

View southwest (downstream) of the Palouse River.
The terraces outline successive basalt flows. (50mm ƒ/2 Rikenon lens)

Do visit Palouse Falls State Park Heritage Site. It is an impressive example of geology and the amazing effects of flowing water. 

Washtucna

Washtucna is a small town in Adams County about 17 miles north of Palouse Falls and about a hour from Spokane, Walla-Walla, and Pullman. The town is at the head of the Washtucna Coulee (again, one of the remnants of the Missoula Floods) and is therefore lower than some of the surrounding terrain. 

The town looked like it had gone through a rough time economically. I saw some interesting subject material along Main Street (Route 261).

El Camino (28mm ƒ/2.8 Vivitar lens)

I took most of these photographs on Kodak Portra 160 film with my Pentax MG camera and Pentax, Vivitar, and Rikenon lenses. Northeast Photographic in Bath, Maine developed the film. I scanned it with a Nikon Coolscan 5000 scanner.

References

Camp, V.E., Reidel, S.P., Ross, M.E., Brown, R.J., and Self, S., 2017. Field-trip guide to the vents, dikes, stratigraphy, and structure of the Columbia River Basalt Group, eastern Oregon and southeastern Washington, Scientific Investigations Report 2017-5022-N, U.S. Geological Survey, https://doi.org/10.3133/sir20175022N

Waltham, T., 2010. Lake Missoula and the Scablands, Washington, USA. Geology Today, pp 152-159DOI: 10.1111/j.1365-2451.2010.00763.x