Thursday, June 3, 2010

Wading into Science

Wading into Science
Caroline Moellering is the School Programs Coordinator at Keystone Science School.


When thinking about summertime in Summit County, your mind might immediately jump to mountains and trails — hiking, mountain biking, climbing and running being the popular recreational activities that they are. Even in this high alpine environment, however, we are lucky enough to have another wonderful source of recreation: water, in the form of lakes and rivers. As our local bodies of water are so close to their sources — melting snow — they're often too cold for swimming and other contact sports, but nonetheless are an aesthetically pleasing part of our environment, an important resource and, of course, provide a rich opportunity to learn about science and nature.

As our local rivers start to emerge from their blanket of ice and snow, there are lots of interesting changes to observe. The most obvious change you might notice as the weather warms is the amount of water flowing through the river. To get a rough measurement of this, choose a specific spot on a river, place a tall, sturdy stick in the water, and mark the water level. Try this on different days (and even times of day) and note the air temperature in each instance. Do you see any patterns? Are levels higher or lower in relation to the air temperature?

Another fun thing to measure in a river is its surface velocity (or how fast it flows) and to determine how that velocity changes as the amount of water in the river increases. One student at Keystone Science School was excited to share a story about how he made a boat out of sticks and grass with his parents, then sent the boat down the river to see what it would do. This is a great way to measure surface velocity. To try it, measure a relatively straight section of river and create a small craft out of natural materials you find on the river bank (you could even simply use a small, lightweight stick). Then time how long it takes for your object to get from the beginning to the end of that measured section. The distance divided by the time gives you the surface velocity. Try doing this at different times throughout the summer to see how the numbers change with the rise and fall of water levels. Water can run very quickly and strongly at times, so always be very careful as you're performing your experiments!

While you're studying the amount of water, take note of the shape of the river and the changes that occur as the river rises. In spring, when water levels tend to be higher, you will be able to see higher rates of erosion along the stream banks (especially on the outside of curves), which makes the stream channels a little wider. The river bed materials picked up by water are dropped off in other parts of the stream when the water slows down. Watch your stick/boat to see how the water starts to slow down on the inside of a curve. At those points you will probably find what looks like a ‘beach' of rocks or gravel deposited by the water.

These are just a couple of examples of the many things you can learn about our local rivers by getting out and exploring. Keep an eye out, too, for signs of animals (trout and beavers are plentiful), riverbank vegetation, and notice what kinds of bugs hang out around the water. There's a whole world to discover when you take the time to investigate!

Caroline Moellering is the School Programs Coordinator at Keystone Science School. She can be reached at (970) 468-2098.