Views from Palisades and High Bridge Parks
Palisades Park
The Palisades Conservation Area encompasses 700 acres and provides a spectacular overview of the main Missoula floodpath through the Spokane Valley, which was then occupied by glacial Lake Columbia. The Park is at the top of a basalt bench historically referred to as rimrock and characterized by large boulders of fractured basalt undermined by the megaflood which widened Spokane Valley. In the far distance, well above the flood debacle, is Mt Spokane, highest peak in the Selkirk Range.
This park’s trail system consists of a mixture of converted road bed and single trackways meandering through Ponderosa pines interspersed between flowered meadows, including seasonal wetlands, scour pools and isolated outcrops of columnar basalts, typical of megaflood erosion found in the Channeled Scabland.
If you stick to the upper trail on top of the bench emanating westward along Rimrock Drive, you will see spectacular wildflower blooms in the spring and little elevation gain. For the more adventurous hiker, head south along Rimrock Drive and drop down 200 feet to Indian Canyon Mystic Falls, which cut into and expose pillow basalt found below the rimrock.
Highbridge Park
An exceptional cliff exposure of the Missoula megaflood deposit, which once filled the Spokane Valley, can be viewed along Latah Creek near the confluence with the Spokane River. This exposure can be viewed from an extensive gravel bar within Highbridge Park that can be reached by a short hike along a dirt road trail from the parking lot near the intersection of Riverside and Clarke Avenues. You can see within this 60-foot exposure of a cross-bedded megaflood deposit, visible channeling, gravel lenses (pinching in and out of channels), scour depressions and a big boulder filled channel just below the terraced surface. A small exposure of Mt. Mazama ash dating back to 7,700 years ago occurs at the top of this terrace marking the past elevation of Latah Creek. Standing at the confluence is Mike McCollum, who provided much helpful info about the flood features.
Another reason to visit this site is that archaeologists excavated and recovered anthropological evidence that this flood gravel bar was a very important fishing site and gathering place for indigenous people for at least 8,000 years. We invite all the IAFI members to join us in early June for another multi-day Annual Fieldtrip Jamboree and we will even include these two parks in our agenda. So those of you who are interested in seeing the evidence suggesting that the Spokane Valley was carved out by the Missoula megafloods might want to sign up soon, space is limited. Who knows, but maybe our region’s flood history may not be that different from those of you residing in the Channeled Scablands after all.
This article is a collaboration between IAFI Cheney-Spokane board members Dr. Linda McCollum, President; Jim Fox, Vice President; and Don Chadbourne Treasurer