Final Report From Preston High School
-Lower Youghiogheny River
Before completing the water sampling tests, we had hypothesized that our water would be reasonably clean and hospitable to aquatic life. In appearance, our river is clear and constantly flowing. There is no large growth of algae or harmful plant life, while small mammals, fish, and waterfowl have been previously observed between the riverbanks. Perhaps the most interesting bit of information is that the river skirts around the town of Oakland, Md. There are no visible sources of industrial pollution or public littering, and fishermen frequent the banks of the river. We expected to find noticeable quantities of both phosphates and nitrates due to a large number of farmlands in the surrounding area, but not to find them in harmful quantities. Our belief for pH was that the water would likely be slightly basic (greater than a pH of 7) due mainly to fertilizer runoff.
Water was sampled four times on the dates March 29, April 16, April 30, and May 5, and the data collected was averaged for submittance to the Global Water Survey's collected data.
Temperature of the water was taken at each sampling; the water temperature ranged from 11.1 °C (52 °F) to 17.2 °C (63 °F) and averaged 14.6°C (58.3 °F). The variance of temperature was important in my collecting in both general observations and tests for dissolved oxygen, phosphates, and nitrates. Dissolved oxygen concentrations can be higher at cooler water temperatures due in part to oxygen solubility, so I expected DO concentrations to be greater for the earliest samplings. Similarly, with my initial tests earlier in the year I did not expect much farm runoff from field treatments.
Readings of pH ranged from 7.2 to 7.5 (averaging 7.4) and fell within my predictions of a slightly basic nature. The readings earliest in the year (before much farming activity) were taken as 7.2, while the reading taken later in the year (as treatment of fields was underway) increased to 7.5. These observations first led me to believe that agricultural activity was to have a great impact on the water quality of the river. Data taken from testing amounts of phosphates and nitrates would have to be an indicator of how true that conclusion was in actuality. Still, the readings of slightly above 7 are well within the range of being hospitable to aquatic species.
Dissolved Oxygen readings varied from 9.5 ppm to 7.5 ppm over the course of testing, with an average reading of 8.5. Excellent levels of DO are around 8 ppm so the results from the testing showed a healthy level. DO is possible in greater concentrations in colder water and was found likewise in my testing. Previously unfamiliar with DO, I could not easily hypothesize an expected level; the results though show the river to be quite healthy in the respect of DO.
Nitrates and Phosphates were expected to be found in noticeable quantities, but not in harmful excesses. Readings of nitrates varied from 0.25 ppm to 0.50 ppm and averaged 0.41 ppm, while reading of phosphates varied from less than 0.05 ppm to 0.1 ppm and averaged about 0.05 ppm. Results for both of these tests were surprising. I had expected much higher amounts of both quantities than was apparent. The amount of agricultural runoff was less than expected for perhaps a variety of reasons. First, full scale treatments of fields had not completely gotten underway; less chemicals would be on the ground to wash away. Second, there may be less runoff into the river than I had first suspected. These factors have yet to be analyzed, but may prove an interesting project in the future.
In (somewhat lengthy) conclusion, the Lower Youghiogheny was found to be a cleaner river than even I optimistically suspected. All required water tests were found to be excellent in possible hospitality to aquatic (both plant and animal) life. The river is surprisingly well taken care of; I hope others had similar results.
Conclusively, Scott Kelly and Samplers from Preston High School