It took a while for me to actually see that rivers have a lot of brown in them. It's all that mud on the bottom, and the rocks below, and shade around them. Here in New England, a lot of the water I look at is blue, or deep gray, or sometimes that dark green/blue/gray. If you're from around here, you know what I mean.

The rivers out in Idaho are a different thing entirely. In the foreground they tend to be a warm sepia tone, then they darken up in the mid-ground. And far, far in the distance they are often light, reflecting the sky.

It's too much for a girl from these parts to comprehend. I'm going to search out some of my local rivers and see how they behave. It's high time to check out the newly renovated Deerfield Inn, which had it's own troubles with river waters. And I can usually lure John into a ride if it ends with Bub's Barbecue in Sunderland, MA. 
I'll be sure to post my findings.