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4:15 a.m. - May 24
My alarm clock goes off. I quickly slip out of bed and pull on my clothes, then disappear into the darkened hallway to do a final check on my field equipment. As soon as I finish loading my equipment into the trunk of the car, I am ready to head off to my first test site, 45 miles away. Background For the past three years I have been comparing the water quality of the rivers flowing into and out of Utah Lake. Utah Lake is a freshwater lake located in north central Utah. It is 24 miles long, eight miles wide, and at its lowest point, 14 feet deep. It is also home to the June Sucker, an endangered species of fish. The June Sucker is not a bottom-feeder like most suckers. Its mouth is positioned so that it can eat zooplankton mid-lake. Unfortunately, its numbers are rapidly declining due to pollution and the destruction of its spawning areas. Another thing threatening the June Sucker is competition from non-native species such as carp. This is a serious problem because Utah Lake is the only place on earth this species can be found.  Site map of Utah Lake and Spanish Fork River system (Click to enlarge) After reading up on the river and interviewing some local scientists, I still had many unanswered questions. I decided to set out on an expedition to see if I could figure out what was going on. I hypothesized that human activity was playing a major role. Sites I picked seven sites to test along the Spanish Fork River system (Appendix I). The first three sites were the tributaries that create the Spanish Fork River: Thistle Creek, Soldier Creek, and Diamond Fork River. By testing these sites, I could figure out which pollutants were flowing into the Spanish Fork River at its head. The next spot, Site 4, was located in the Spanish Fork Canyon after the tributaries meet. Sites 5 and 6 involved urbanization; one was located above the City of Spanish Fork (pop. 20,000) and one was below. Site 7 tested the effects of agriculture. It was also the site where I had done earlier research and had found such poor water quality. Dissolved Oxygen Testing  Site 1: Thistle Creek The car pulls onto a gravel turnoff at the side of the road, and the race begins. I must test all seven sites for dissolved oxygen before the sun comes up because as soon as the sun hits the water, algae start to photosynthesize and will throw off my results.  Shannon gathering a sample
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The sun starts peeking its head over the mountaintops of the Wasatch Range as I finish up with Site 7. Whew! I have gotten all of the dissolved oxygen testing done just in time.
Other Chemical Testing With dissolved oxygen out of the way, I concentrate on testing for nitrate, phosphorus, and pH. Luckily, these tests can be done when the sun is up.  Shannon testing a water sample My test for phosphorus uses a reagent packet that is added to a sample of river water and is then compared against a second sample to determine the change in color. Phosphorus provides food for plants and is consumed very quickly. If you find too much phosphorus in a stream, however, it is probably inorganic phosphorus, which is often a man-made pollutant. PH testing is done by dipping a pH strip into river water, then comparing it with a color guide. Both high and low levels of pH can be deadly—high being basic and low acidic. Things like decaying leaves and other plant material can cause acidic pH. On the other hand, limestone or chemicals such as bleach and most soaps cause pH to rise and become more basic.  Site 7, Spanish Fork River (Click to see 6 month overview) Site 7, Spanish Fork River (downstream agriculture) Nitrate - 0.1 ppm Phosphorus - 0.1 ppm pH - 7.5 Physical Data With the chemical testing done, I start collecting physical data. The first thing I do is take the temperature of the water. Temperature is an important physical factor because scientists use it to categorize a river, and it helps define what types of fish can live there. The Spanish Fork River is classified as a cold water fishery. Water temperature is also important because it affects the amount of oxygen that can be dissolved in the water and the toxicity of chemicals. The next thing I do is measure turbidity. This involves a long clear tube with a checkered disk at the bottom. I dip the tube into the river, fill it with water, and then watch the water as it drains out. When I see the black-and-white-checkered disk, I close the faucet on the side of the tube and measure how many centimeters of water are left. High turbidity often indicates an erosion problem upstream. If there is too much sediment in a river, plants and animals start dying off. Stream width and depth are measured so you can find the cross-section of the river. The cross-section allows you to figure out if the river is channelized or has other structural problems. It also gives you the numbers needed for the formula for flow rate.  Shannon taking river measurements To determine velocity, I put a large pinecone in the water and time it as it floats downstream for 50 feet. How fast the river flows has an impact on what kinds of habitats can exist; usually, the faster the flow, the less variety of life is found. Temperature - 68.2° F Turbidity - 19 centimeters River Width - 25 feet Average River Depth - 13 inches Velocity - 0.9ft/sec Before leaving Site 7, I quickly snap a few pictures with my digital camera and jot down some notes about the riparian zone. The riverbed at this site has been channelized, and the bottom is filled with silt and sand-sized substrate. The west bank is mainly covered with cottonwood, scrub oak, and poplar trees, many of which have great branches stretching over the river. The east bank is covered with tall grasses and occasional Dalmatian Toadflax. Watering cattle, trying to get to the river, have trampled large gaps through the trees and grasses. With the data for Site 7 collected, I am ready to retrace my steps back upstream and repeat the same procedures at the other six sites. |
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