WatershedEvents

Chum Salmon and the Weathering Process

Chum salmon contending for position over a spawning female (obscured by wave action photo left)

As I've written several times previously, each November chum salmon spawn in a small ephemeral stream not more than a quarter mile from our front door. Beatty Creek it's called, and I have loved it since the first time I laid eyes on it. This creek differs in almost every respect from Fanno Creek, particularly with regard to its bottom. The waters of Beatty Creek flow over deep beds of well sorted gravel; those of Fanno Creek flow over a bottom that is almost entirely composed of an exceedingly fine mud. 

Ironically, these creeks share a common ancestor: the Fraser Glaciation that invaded Washington State during the last glacial maximum. Fanno Creek's geological history is tied to the Purcell Lobe of that glaciation and its relationship to the great Missoula Floods that took place 16-12,000 years ago. The creek lies in the Tualatin Basin, a deep bowl of land in northwest Oregon. The Missoula Floods visited this basin at least once, leaving behind vast quantities of debris, including millions of tons of loess. The muddy bottom of Fanno Creek is directly attributable to that great abundance of that material. 

Beatty Creek, on the other hand, owes its salmon-friendly, gravely bottom to the Puget Lobe of the same glaciation. As that monstrous body of ice plowed through the Puget Sound, it carried with it enormous quantities of mineral-rich rocks it had literally ripped out of the mountains of British Columbia and Washington. When the glacier retreated, around 12,500 years ago, it left behind great piles of rocky debris, which in turn were washed and worn by glacial meltwater and all the other agents of the weathering process. The deep glacial drift that covers the lowlands of the Puget Sound are one of the artifacts of that weathering process. 

Great things happen when the rains of October and November flow through the ancient gravels of the Beatty Creek watershed. 

 

The Chehalis River Basin and The Gate Pathway

In April I began to think seriously about starting work on a new book. The idea had come to me a month earlier as I was nearing the end of my first read of a 1913 scientific paper written by J Harlen Bretz (Glaciation of the Puget Sound, Bulletin #8, Washington Geological Society). I stumbled across this paper when I was looking for information about Dry Falls. I've known of Bretz and his Scablands work for many years and even wrote a segment about Glacial Lake Missoula for my book on Fanno Creek. However, until I read that article and began digging a little deeper into Bretz's earliest years as a geologist, I had no idea he had begun his field work as a glaciologist.

It is now closing in on the end of June, and I am close to going all in on the project. I've been testing the waters by sharing an outline of my ideas with folks whose opinions I deeply respect. One of these people is a writer and publisher who is also married to an engineering geologist. Their immediate responses were particularly encouraging, because I am sure either of them would have told me not to waste my time if they had seen little promise in the venture. I've also shared the outline with a handful of well-placed and Bretz-savvy geologists, who have shown considerable interest in the project.

All in all, the uniformly positive and enthusiastic responses I've received are very encouraging. It looks as if I have a good story in hand, one that could be marketed to a national audience. The only hang-ups now - besides the perennial practical ones - is the same ones I had a hard time getting past when I was just beginning to write Up Fanno Creek: will my writing skills live up to the subject matter, and do I have the strength of character it will take to see it through to the end? 

The differences between this book and the Fanno Creek effort are many; however, telling this story will demand (1) a greater commitment of time, money and spiritual capitol; (2) a significantly higher caliber of research; and (3) a far greater degree of artistry. Quite frankly, I'm not sure I pack enough gear for the long haul I am certain it will be. 

To help me get in closer touch to some of the material, I've begun visiting a few of the areas Bretz wrote about in his paper. The Chehalis River Basin is one of those places and figures large in the story of the Puget Lobe glaciation. Roughly 12,000 years ago, as the glacier was retreating out of the upper reaches of the Puget Sound, the Chehalis river became an absolute monster. I'm not ready to tell that story in detail right now, but it will certainly be included in the book.  

Over the next few weeks I hope to make several trips through the middle part of the basin - the reaches between Grand Mound and Elma. It was roughly along this line where the snout of the Puget Lobe reached its most southerly advance. I'm not sure where Bretz worked when he visited this area, but I'm sure I'll cross his track from time to time. For example, I am pretty sure he once tramped along this section of railroad track. There was a small community near this sign in Bretz's day, but it was well on its way to dying, thanks to a devastating fire in 1900, followed by the failure of the area's timber industry in the years that followed.

My next post will be about the Black River, a tributary of the Chehalis, and one time a bit of a monster in its own right.  

 

The Bug Chicks

Have you stopped off at the Bug Chicks site? Make sure you do, you won't regret it. I was so inspired by my visit to their site that I decided to post a photo I took while waiting to photograph the controlled burn that took place in Cook Park a few years ago. This gal had a burrow in the loose material next to the railroad berm that separates Cook and Durham Parks. She was busy that day and made more than a dozen trips out and back in the short half-hour I spent lying on my belly outside her door.