I asked about your pet immoderations. About two weeks ago, one of my favorite teachers tweeted:
I love going into seclusion; there’s nothing better in all of life.
She reminds me of one my favorite rivers — THE poster child for what hydrologists term entrenchment.
Entrenchment describes a river’s relationship to its surrounding landscape. It’s measured by how a river responds to increased flow. When life really starts to rock-and-roll, some rivers spread way out and inundate a huge wide floodplain. But the entrenched river has a high degree of “vertical containment.” She gets deeper and deeper without becoming much wider.
Is this okay?
Popular psychology sometimes worries about secluded individuals. So does hydrology. And yet two types of healthy natural rivers ARE quite thoroughly entrenched. One is the step-pool system I described earlier. The other is perfectly personified by my friend:
- considerably entrenched down in some highly weathered material — she’s picturesque both at the close scale and from a panoramic viewpoint;
- meandering through riffle/pool sequences – boaters love her intermittent respites almost as much as her thrilling rapids; and
- flowing at low gradient in a relatively wide channel — unlike steep, straight, narrow waterfalls and cascades, my pal’s quite accessible.
People from all over the world invest great effort and money just to be in her presence:
So if one of the Seven Natural Wonders is a classic example of entrenchment…
… then why the bad rap?
1. It’s a question of foundation. Again.
An entrenched channel has a trapezoidal shape (unusual in natural streams though a favorite in engineering designs!) AND high stream banks. Physics-wise, this combination directs so much force onto the sidewalls that an entrenched river based on any material smaller than a Volkswagen WILL erode. Typical silt, sand, and gravel rivers simply can’t do well when disconnected from an expansive overflow area.
But the Colorado River (and my teacher) incised herself through layer after layer of solid rock. As we discussed last month, a river with a solid base will always thrive. The same holds true with humans. Regardless of individual style, when you cultivate a clear, free mind, you’re carving a life in bedrock.
2. What’s left behind
Hydrologists put it like this: “entrenched rivers develop by abandoning their historic floodplains.” What’s left behind is no longer directly nourished by the river. That community (soil, plants, animals) converts to a different ecosystem. Plus now only a flood of huge magnitude makes the entrenched river over-top her banks — she can manage most action on her own. The adjacent flat is no longer indispensable. That’s a lot of change for folks to handle.
3. A reminder
Here’s how The Colorado herself responds to my mentor’s tweet.
Dear Teacher to Many,
Entrenchment reminds us of what trauma does – it makes a river downcut, often steeply and in a hyper-straight fashion. I imagine it’s similar with people. When the down-cutting ceases, the river’s back to her innate slope, albeit at a “deeper level,” and the river begins to broaden herself in order to once again create space for meandering.
This healing stage is a joyfully entrenched one.
No wonder we awe, frighten, and inspire.
Yours — C
And that’s one reason why the Colorado River and Martha Beck are my heroes.