This study focused on Atmospheric Deposition (AD) loading on Utah Lake. Utah Lake is susceptible to Harmful Algal Blooms (HABs) because of its large surface area to volume ratio, proximity to Great Basin dust sources, and various wind patterns from close mountain ranges that blow AD towards the lake. In this study, we continued the collection and analysis of AD samples that started in 2017 and 2018, while reporting additional 2019 and 2020 data. We constructed a sampler on Utah Lake itself, which allowed us to better estimate how AD loads were distributed over the lake. An interpolation assumption was made in the previous studies that the amount of AD decreases exponentially as it passes onto the lake from the shore. Results from 5 months of Bird Island AD sampling on Utah Lake indicate that this assumption was incorrect. We performed statistical comparison tests on 2 variables: (1) the difference in AD between 2 table heights at the same site and (2) the difference in AD between a filtered sample and an unfiltered sample. We were able to statistically conclude that there was no difference in AD between 1-meter and 2-meter tall sample tables and that filtered AD samples had as much as 3 times lower concentration than unfiltered AD samples. In 2017, the total AD loading was estimated to be, on the high end, approximately 350 tons of total phosphorous (TP) and 460 tons of dissolved inorganic nitrogen (DIN) (Olsen JM, 2018). After making some changes to the interpolation methods, Joshua Reidhead in 2018 estimated AD loads of 153 tons of TP and 505 tons of DIN (Reidhead, 2019). With no changes to the 2018 sampling methods, but using an updated interpolation method, we determined the AD results for Utah Lake in 2019 to be 262 tons of TP and 1052 tons of DIN. After adjustments to the sampling tables, the bucket filters, and incorporating the Bird Island sampler results, we calculated the 2020 AD loading totals to be 133 tons of TP and 482 tons of DIN on the lake.
College and Department
Ira A. Fulton College of Engineering and Technology; Civil and Environmental Engineering
BYU ScholarsArchive Citation
Barrus, Seth Michael, "Improvements of Atmospheric Deposition Sampling Procedures and Further Analysis of its Impact on Utah Lake" (2021). Theses and Dissertations. 8940.
Utah Lake, atmospheric deposition, total phosphorus, dissolved inorganic nitrogen, eutrophic, harmful algal blooms