Skip to main content

Washington State Route 155 and the Coulee Corridor

I recently took US 2 across Washington State from Leavenworth to Spokane, but decided to make a detour up to the Grand Coulee Dam. The detour took me up WA 155 from Coulee City along Banks Lake to Grand Coulee, through a place where roads meets epic geologic history. WA 155 is part of the Coulee Corridor National Scenic Byway, boasting quite a number of scenic views as it goes through the Grand Coulee.


The story of this stretch of land begins a long time ago, during the Ice Age. There was a large ice sheet known as the Cordilleran ice sheet that covered western Canada, as well as portions of Idaho, Montana and Washington State. Towards the end of this glaciation, about 12,000-15,000 years ago, a large ice dam blocked the Clark Fork River in the Idaho Panhandle, creating Glacial Lake Missoula. Glacial Lake Missoula was a massive lake 2,000 feet deep, filling the valleys of western Montana, stretching more than 200 miles. At its maximum height and extent, the lake contained more than 500 cubic miles of water. Every so often, the ice dam would fail, resulting in a large catastrophic flood, rushing across northern Idaho and eastern and central Washington, down the Columbia River, through the Columbia River Gorge, and finally poured into the Pacific Ocean at the mouth of the Columbia River.

Thundering waves and chunks of ice stripped away hundreds of feet of soil, carved  mountainsides into deep canyons, or coulees, into the underlying bedrock, deposited giant ripple marks, created the Channeled Scablands of Eastern Washington and carved the Columbia River Gorge. When Lake Missoula burst through the ice dam and exploded downstream, it did so at a rate 10 times the combined flow of all the rivers of the world and at speeds of about 65 miles an hour, draining in as little as 48 hours. This towering mass of water and ice literally shook the ground as it thundered toward the Pacific Ocean. Grand Coulee, along with Dry Falls and Palouse Falls were all were created by these flood waters.

Today, the flooding is over, but the evidence of the Missoula Floods remain. WA 155 travels alongside a canyon that was once one of the channels of the Columbia River during these floods. It makes for a nice and memorable drive as the road meanders along the east bank of the 27 mile long Banks Lake and passes by Steamboat Rock State Park. Let's take a ride now, shall we?


We start near Coulee City, where US 2 veers east through rolling hills and pastures on its way to Spokane. We're some 27 miles away from the Grand Coulee Dam at this point. A few miles southwest of here is Dry Falls, which is an ancient waterfall that was once the world's largest waterfall.

You can start to make out the canyon walls that make up the edges of the coulee. There's also some grazing land for cattle.

Riding the edge of the canyon that will follow the roadway most of the way to the town of Electric City.
I spy a grand opening...

And boom goes the dynamite. That's an incredible view.
Banks Lake to our left, canyon walls to our right.

Obligatory WA 155 shield photo.

Steamboat Rock
Heading into the Northrup Canyon. This is a good area to go hiking and even see bald eagles during the winter.

Back to Banks Lake and canyon walls.
Getting into the outskirts of Electric City...

...and arriving at the junction of WA 155 and WA 174 in Grand Coulee. Both towns are near the Grand Coulee Dam. This is where our story ends, but there is a neat engineering marvel that you should see first.
If you so desire, you can check out the Grand Coulee Dam, which is just a couple miles to the north.


Sources and Links:
Scenic Washington State 365 - Coulee Corridor National Scenic Byway
Montana Natural History Center - Glacial Lake Missoula
The Columbia River: A Photographic Journey - Missoula Floods



How to Get There:

Comments

Popular posts from this blog

California State Route 232

This past month I drove the entirety of California State Route 232 in Ventura County. CA 232 is an approximately 4 miles State Highway aligned on Vineland Avenye which begins near Saticoy at CA 118 and traverses southwest to US Route 101 in Oxnard.  The alignment of CA 232 was first adopted into the State Highway System in 1933 as Legislative Route Number 154 according to CAhighways.org. CAhighways.org on LRN 154 As originally defined LRN 154 was aligned from LRN 9 (future CA 118) southwest to LRN 2/US 101 in El Rio.  This configuration of LRN 154 between CA 118/LRN 9 and US 101/LRN 2 can be seen on the 1935 California Division of Highways Map of Ventura County. 1935 Ventura County Highway Map According to CAhighways.org the route of LRN 154 was extended west from US 101/LRN 2 to US 101A/LRN 60 in 1951.  Unfortunately State Highway Maps do not show this extension due to it being extremely small. During the 1964 State Highway Renumbering LRN 154 was assigned CA 232.  Of n

Former US Route 50 and the South Lincoln Highway from Folsom east to Placerville

The corridor of Folsom of Sacramento County east to Placerville of El Dorado County has been a long established corridor of overland travel dating back to the California Gold Rush.  The Folsom-Placerville corridor was once part of the path of the Lake Tahoe Wagon Road which became the first California State Highway and later the South Lincoln Highway.  In time the South Lincoln Highway's surface alignment was inherited by US Route 50.  The Folsom-Placerville corridor also includes the communities of; Clarksville, Shingle Springs and El Dorado. Part 1; the history of the Lake Tahoe Wagon Road, South Lincoln Highway and US Route 50 through Folsom-Placerville Folsom is located on the American River/Lake Natoma of eastern Sacramento County.  That lands now occupied by the City of Folsom were part of Rancho Rio de los Americanos prior to the finding of gold at Sutter's Mill during 1848.  During the California Gold Rush the lands of Rancho Rio de los Americanos were purchased by Jose

US Route 101 through Gaviota Pass

US Route 101 in the Santa Ynez Mountains of Santa Barbra County, California passes through Gaviota Pass.  Gaviota Pass is most well known for being part of El Camino Real and the namesake Gaviota Tunnel which opened during 1953.  Since 1964 Gaviota Pass and US Route 101 have also carried a multiplex of California State Route 1.   Part 1; the history of the Gaviota Pass corridor Gaviota Pass is historic path of travel through the Santa Ynez Mountains of Santa Barbra County.  Gavoita Pass was a known route through the Santa Ynez Mountains which was utilized by the Chumash tribes before the arrival of Europeans.  Gaviota Pass was first explored by Spanish during the 1769 Portola Expedition of Las Californias.  The Portola Expedition opted to follow the coastline northward fearing that the established Chumash path through Gaviota Pass was too narrow to traverse.  In time Gaviota Pass became a favored established path of Spanish travel which bypassed the hazardous coastline as part of El C