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An Advanced Biology Adventure

By: Chyann Erickson

ALMA — Every year the students in Colfax High School’s Advanced Biology class embark on a life changing adventure, an adventure that tests the mind, the body, and one’s fishing ability. Our journey took us through town after town to arrive at a little place along the Mississippi River nestled at the bottom of vibrant green rolling hills, called Alma.

The spring quarter arrives with much anticipation from the Advanced Biology students. It means that we are finally done learning from the textbook, and we get to go outside to learn about things in the environment with the main focus being water. Our town is very fortunate to have a creek running through it; we get to study things and do research on it that many other schools are not given the opportunity to do. In the beginning of our water testing unit, we go to the 18 Mile Creek and do several different forms of tests to gather a wide range of information like turbidity, velocity, and the dissolved oxygen. Performing some of these tests on different rivers was the whole objective of taking our field trip to the Mississippi River.

On the morning of the trip, we had to arrive at the school by 5:00am because we would be leaving by 5:15am. Many students were tired and wrapped up in blankets to keep warm as we waited outside the school for the bus to arrive and take us on our adventure. However, 5:15am came and went with no signs of a bus. As the time was drawing nearer to 6:00am, Mr. Mosey decided to call around and see what the problem was. He got off the phone and told us there was no bus coming for us. He then proceeded to tell us that we had a few options on what to do; we either completely rescheduled the trip for a later date or we waited until after 8:00am to see if someone would be willing to drive us. Obviously, everyone already had their hearts set on not going to school for the day, so it was unanimously decided that we were going to wait to get a bus at 8:00am.

In the meantime, students were allowed to go home and scrounge up a couple more hours of sleep; others went out to breakfast. A few of us went down to the Red Cedar River with Mr. Mosey to test the turbidity and the dissolved oxygen. We trekked down to the water’s edge to do our tests. The water entering the Red Cedar from the 18 Mile Creek was very murky and full of sediment from the two inch rainfall the night before; its color was very close to chocolate milk. The turbidity was a measly 5 cm and the water was too murky to even do a dissolved oxygen test in that particular spot. Because those results were unsatisfactory we went upriver from the 18 Mile Creek and redid the tests, getting 15.3 cm for the turbidity, which is a lot better than 5 cm and getting 5.4 parts per million for the dissolved oxygen test.

Turbidity measures the clarity of water. This is done by taking a sample of water from the center of the river (to be sure not to get any excess sediment) and put it in a turbidity tube. A turbidity tube is a clear plastic tube about four feet long that has a hose coming off the side; it has measurements along the length of the tube in centimeters to determine the depth of clarity. The higher the number, the clearer the water. The lower the number, the murkier the water is. Taking the water obtained from the river, a person pours it into the tube and look down into it. At the bottom of the tube there is a black and white indicator disk, so when looking down into it, if the indicator cannot be seen, release water from the tube by letting it flow out of the attached hose being sure not to let the water run out too quickly. As soon as the indicator can be seen, stop the water flow and record the depth of water left in the tube. That is how the turbidity of a river is found.

The dissolved oxygen test’s purpose is to determine the oxygen available to aquatic organisms. To do this, we start by taking two samples of water from the river. We place one of the sample bottles in the dark and leave it for five days (5 Day Biological Demand Test). The other sample has chemicals added to it right after we get it from the river that makes it form a precipitate and turn a yellowish orange color. After this happens, eight drops of sulfuric acid are added and the solution is shaken up to mix it all together. The water will then go back to its original consistency. After transferring 20 mL of the sample to a mixing bottle, a special syringe made specifically for this test is filled with sodium thiosulfate and then used to change the yellowish orange liquid to a pale yellow color one drop at a time. Once the color becomes pale yellow, eight drops of a starch indicator are added that make the water turn a deep indigo color. We continue adding the sodium thiosulfate, swishing the solution around after every drop until the dark liquid returns to clear water. Reading the amount of sodium thiosulfate left in the syringe is how you find the oxygen dissolved in parts per million. Then five days later a person takes the second sample of water and does the same process. Subtracting the first dissolved oxygen from the second will tell you exactly how much oxygen is being used by bacteria while consuming excess nutrients caused by runoff from nonpoint sources.

After we were done at the Red Cedar River, it was about time to meet back up at the school to get on the bus that would take us to Alma. With everyone reassembled, we boarded the bus with renewed energy and we were on our way! Because the field trip started three hours later than it was supposed to, the number of stops we could make at various rivers for testing was cut down from the Red Cedar, Chippewa, Buffalo, and Mississippi Rivers to just the Red Cedar and Mississippi. It was a bummer that we could not go and visit all those places, but I was very happy just going straight to the Mississippi River. Upon arriving in Alma, I was awestruck. The landscape and town itself was so beautiful. I especially liked how the town seemed to be nestled into the hillside. Even the factory there looked somewhat pretty against the backdrop of the rolling, green hills. My favorite part of the whole trip was just sitting and admiring the beautiful landscape and being outside to enjoy it. I had never been to Alma before, and I could not believe this beautiful place was just a short distance from Colfax. The town itself was so quaint and pretty, I cannot wait to go back and explore everything it has to offer sometime in the future.

Across some railroad tracks and down a little hill with stairs onto a rickety old dock, we all squished into a little passenger boat for a less than five minute ride to the fish float on the Mississippi River. The float connected to the left side of the river bank just below the lock and dam. Once we got there, many dispersed to try their luck at fishing, others went to explore the shore adjacent to the float. Sitting on the fish float was my favorite part of the whole trip, not because I caught some huge trophy fish, but because I was so content sitting on the float and just being outside. I liked sitting there and feeling the enormity of the world while eating my lunch. Plus it was entertaining to see some pretty large fish jumping out of the water despite the fact that the fishermen still were not catching any. It was cold at times but honestly that did not bother me. I would rather it had been a little chilly out than blazing hot.

As the day passed, eventually it was time to leave this place I had grown quite fond of. Getting back on the bus, I had the bittersweet feeling of being glad that I had been introduced to this place, but sad because I had to depart so quickly.  Our adventure was not over yet though, on the way back home, we drove through Nelson and stopped at the Nelson Cheese Factory for ice cream! It was amazing, and I would recommend their ice cream to anyone. We then boarded the bus and made the hour trip back to Colfax.

For anyone who has not been to Alma, I highly suggest going because it is a very worthwhile trip and the memories made there will be with me forever. I will recall them fondly as I return sometime down the road. Even though there was a minor setback in the beginning, I am so grateful that we went on the trip.