Tom Ross: The unseen determines water traits
July 22, 2011
Steamboat Springs — I was standing on the banks of the Yampa River on Friday morning pointing my newfangled iPhone 4's video camera at Kevin McBride when a trout broke the water.
McBride, who is the general manager of the Upper Yampa Water Conservancy District, was describing water quality issues to a small group of river lovers hosted by Yampatika when the trout interrupted him.
The fish was a chunky rainbow that was either feeding on mayflies or just plain wanted to mug for the camera. If my smartphone had a fly rod app, I probably would have gone after the fish. But it didn't make a repeat appearance and the group quickly refocused on McBride's description of how there's much more to water quality than meets the eye. Another way to put it would be to say that there's much more to water than H2O.
"The only time water is in its pure H2O state is when it's a vapor," McBride told the group. "And as soon as it has turned into liquid water things start to dissolve in it. The first thing that dissolves in it is gases, and the most important gas from a biological statement is oxygen."
Trout and other cold-water species of fish are better off when ample summer flows aren't warmed as readily by the sun and the water is able to take up more dissolved oxygen. A river like the Yampa aerates and captures oxygen wherever it splashes over boulders.
That could explain why our rainbow jumped on cue Friday morning. The Yampa has run deep and cold all month as it has posted daily records for the amount of water it is carrying.
At least to the eye, the Yampa has looked exceptionally healthy this year, even when it was flowing through my driveway in June.
McBride predicted the town stretch of the Yampa would probably get a clean bill of health when the results of the newest tests are known, but that report will depend on things we cannot observe with our eyes.
"You have dissolved gases and you have dissolved solids like road salt," McBride said. "And as the river starts to move and has power, then you have suspended solids. Everything else in water quality is related to the what and how of those three things — dissolved gases, dissolved solids and suspended solids."
Dissolved phosphorous is the major limiting nutrient on growth in aquatic environments, McBride said. Phosphorous naturally leeches out of rocks and minerals in riverbeds, but other sources are industrial fertilizers and the discharge from water treatment plants, McBride said.
Some phosphorous in rivers is desirable, according to the Minnesota Department of Natural Resources, but too much can cause unwanted algae blooms that rob the stream of oxygen when the plant matters decay.
Fortunately, it doesn't look like we'll have to worry about algae blooms in the Yampa River this season.
Enjoy the beauty of the Yampa at record July flows this weekend as you make your way between athletic events and outdoor concerts. And take a few minutes to think about the stuff that washes down the storm drains in your neighborhood. I know of a trout in my neighborhood who will thank you for it.
To reach Tom Ross, call 970-871-4205 or email tross@SteamboatToday.com