Submitted by Greta Carlson, Jake Paulsen

We measured three different sections of the stream and found the width, length, depth, and surface velocity of the sections we measured. To find the depth, we measured the width across our section of the stream, and measured how deep the water was with a yardstick at one foot intervals. We added the depths together to find the sum of depths. We divided the sum by the number of one-foot intervals we took to find the average depth. Then we multiplied the average depth by the width of our section to find the cross-sectional area. We had to put in a “correction value” because the bottom of the stream was muddy and uneven. To find the surface velocity, we took a tennis ball and a stopwatch, and we floated the tennis ball down the length of our stream section. We recorded how long it took for the tennis ball to go from the beginning to the end of our section. Then, to find the average float time, we added the time (in seconds) together and divided it by the number of trials we did. Then we multiplied the cross-sectional area by the surface velocity to get the stream flow in cubic feet per second (rounded to the nearest tenth).