A re-print, since Rosgen classification got mentioned yesterday…
A lovely stream dances and sparkles down the side of a mountain meadow. Sunlight glints off the wet rocks in the cold water, and in a few still, tree-shadowed pools, the flash of a shadow hints at the presence of trout. A few water striders scoot over the surface. Farther downstream, the little brook slows and spreads gaining the title of River and picking up a little silt, no longer cold and diamond clear but a touch muddy, especially after rain. It winds slowly, starting to meander across the plateau that sits between the mountains to the west and the broken, mesa-capped plains to the east.
Or I could say that the stream went from a Rosgen Aa2+ in a Type II valley to an A/II and then a G4/VIII.
Which description is better? It depends: are you a poet or an engineer? Because both paragraphs mean the same thing. Continue reading
Um, yeah, so I was doing stream classification on a gutter the other morning. Why? Because I was. For reasons known only to water and whoever laid this section of gutter, there’s a fifty foot or so section that has a very nice riffle-pool sequence much like an ideal stream reach, complete with knickpoint and thalweg.
OK. Rewind a bit. When hydrology-types describe streams, creeks, brooks, rivers, bayous to each other, we use some in-field jargon and a numerical classification system developed by a gent named Dave Rosgen (who studied under Luna Leopold, the son of Aldo Leopold.). Streams [bodies of flowing water of any size] have certain characteristics no matter what the stream looks like. There are shallow areas with obstructions called riffles, deeper areas where the water flows more smoothly called pools, and a center of the active channel called the thalweg. Places where bedrock controls erosion (often marked by a waterfall of some kind) are knickpoints. Continue reading
It is rather common for thunderstorms to cause forest and range fires. Lightning flashes down from the cloud, smites a tree or some dry grass, and foomp! Call in Smokey the Bear! What is less common, especially with grass fires, is for the fire to create a storm. That happened out here, last week.
It was impressive. It was awful in both meanings of the word. Continue reading
Yes, it is either the International Day of Labor, which interestingly enough started in Chicago as part of the Pullman Strikes and the Haymarket Massacre/bombing/terror-attack by police (historians are still arguing over that one), or the day to give small flower arrangements to ladies of your acquaintance. Neither tradition seems to be practiced too much in the US, since we shifted Labor Day to late August, and tussie-mussies and other tokens of esteem have disappeared.
So this post is a follow-up to the little grass-fire that happened this past winter not far from where I work.
Bunches of bunch-grass. They will re-sprout in late spring.
Ah, spring, when an evening stroller’s thoughts turn to duck!
Ahem, to avoiding the local wildlife, especially when that wildlife is re-enacting dog-fights straight out of Battle of Britain and Top Gun. Continue reading
To whom belongs the stream? The water under the ground? The water in the clouds? It depends on where you are, how much water there is to divide, and if you got there first and what you plan to do with it. In some areas, a central government or a group of national governments divide up the water and take responsibilities for it. In other places, medieval and Roman law is used by communities.
This little quick discussion is going to focus on water quantity. Water quality has been regulated by various community and customary laws going waaaaay back. One is not to foul water so that downstream users suffer. You are not supposed to dump things [bodies, offal] into wells (unless you are at war). Continue reading
Drought gnaws. You can’t point to a day on the calendar and say, “On November 22, drought started.” It sidles into being as day after day passes without rain or snow, or with just enough to tease but not to produce. Animals that can leave start shifting their territories, and brown gradually, creepingly, replaces green on the landscape. The lack of soil moisture makes the air drier, and the air heats up faster, making rain less likely, which dries the soil, and so on in a feedback cycle.
And then the wind begins. And the dust. And something more than dust, something bitter and sweet and rich and terrifying. Continue reading