Frenchman Coulee, Washington

Steven Dutch, Professor Emeritus, Natural and Applied Sciences, Universityof Wisconsin - Green Bay

When Missoula Flood waters spilled across Washington, they flooded the QuincyBasin which is bounded on the west and south by low anticlinal ridges. More orless simultaneously the floods spilled south into the Drumheller Channels southof Moses Lake and west into the Columbia River near Quincy. The spillways intothe Columbia near Quincy carved two large cataract channels and several smallerones. The two largest are the Potholes Cataracts southwest of Quincy andFrenchman Coulee just north of I-90.

Frenchman Coulee is easily accessible off I-90. Follow the signs for theGorge Amphitheater (Silica Road) and take the left onto Vantage Road. This is a popularrock-climbing area, and extended hiking and parking will require a use permit.Although there are numerous roads in the area, they are reserved for officialuse only.

Silica Road is named for quarries that extract silica-cemented diatomaceousearth from interbeds in the basalts, by the way.

On the opposite side of the river is Ginkgo Petrified Forest State Park, and roads in the park probably offer good views of the coulee, especially afternoon. I haven't been there yet.

## Looking east toward the entrance to Frenchman Coulee. Unlike the spectacular Dry Falls gorge, a road goes down into Frenchman Coulee.
## Also unlike Dry Falls, a waterfall drops into Frenchman Coulee.
## So do cars, presumably pushed off rather than driven off. Although there are places one wonders.
##  This is looking west toward the mouth of the gorge and the Columbia River. The road down the gorge is in the notch at upper left and basically clinging to the cliff. There are numerous roads on the floor of the gorge but they are off-limits without official permission.

Below: Panoramic view of upper Frenchman Coulee. This is a truly wonderfulplace and this first overlook just takes your breath away. Note the gentle butquite definite anticline near the mouth of the gorge and syncline just left(west) of the waterfall.

## This wall of standing basalt columns, only one column thick, is a popular stop.
## The outlet of Frenchman Coulee
## Looking back up Frenchman Coulee
## Small cataract south of the standing columns
## The southern cataract
## Looking south down the Columbia River from the mouth of Frenchman Coulee
## End of the road. Despite the name, the road does not extend to the hamlet of Vantage where I-90 crosses the river.

Below: Panoramic view of the Columbia River from the mouth of Frenchman Coulee

## Left and below: The southern and smaller cataract. The map shows a deep dry plunge pool not visible from this vantage point.
## Left and below: Flood-carried boulders at the mouth of Frenchman Coulee
## Left and below: Views up Frenchman Coulee
## The waterfall with an isolated pedestal in the foreground
## Left and below: columnar jointing in the basalt
## Left and below: fresh angular jointing in the road cut grading upward into spheroidal weathering. 
## Scabland terrain near Frenchman Coulee as seen from I-90.

The Potholes Cataracts are actually much bigger than Frenchman Coulee but less conveniently accessible.There are roads from the east and north that offer access to public hunting andfishing, but the coulees require fairly long hikes. The numerous roads are for official use only and closed to public traffic (though open to hiking.) If you park at any of the access areas for an extended time you will need a state use permit.

This is a practice that is becoming more widespread and to which I amadamantly opposed. Public land is public - the public pays for it and should have access to it. If people want to be couch potatoes, fine. They can pay for their bypass operations out of their own pockets. But don't charge people who are doing something constructive with their time to save money to provide services to those who don't. And if that strikes you as elitist, it'syour Constitutional right to say so, and mine to ignore you. 

View east across the Quincy Basin. The sediment on the valley floor is thick flood sand and gravel.
Left and below: head of one of the potholes cataract coulees.
Left and below: several small ponds have been impounded in the coulees

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Created 21 November 2003, Last Update 07 June 2020