Paper No. 7
Presentation Time: 9:00 AM-6:30 PM

PHOSPHORUS CONCENTRATIONS IN SIX MILE CREEK, MCLEAN COUNTY, IL


SUGANO, Laura Lynn1, HANNA, Laura2, MEINZER, Evan Randolph3, TWAIT, Richard4 and O'REILLY, Catherine2, (1)Geology, Illinois State University, Campus Box 4400, Illinois State University, Normal, IL 61790-4400, (2)Geography-Geology, Illinois State University, Campus Box 4400, Normal, IL 61790, (3)Geology, Illinois State University, Campus Box 4400, Illinois State University, Normal, IL 61761-4400, (4)City of Bloomington, 25515 Waterside Way, Hudson, IL 61748, llsugan@ilstu.edu

Abstract

Maintaining drinking water resources so that they are safe and uncontaminated is important to the economic, social, and environmental quality of life in the United States. Phosphorus nutrient levels influence water quality, affecting life in the water. One of the most damaging ways that high phosphorus levels can affect life in water is through eutrophication. This occurs when a body of water is enriched with dissolved nutrients, such as phosphates, which leads to increased algae blooms, resulting in the depletion of dissolved oxygen available in the water. In our study, we are focusing on the phosphate and total phosphorus concentrations in the water samples in order to determine whether phosphorus concentrations are higher when collected during storm events or base flow conditions. Phosphates are important because they are a limiting nutrient in freshwater environments like our study site, Six Mile Creek. Total phosphorus is toxic to animals and humans in high amounts so it is important to periodically measure total phosphorus levels. In this study, we collected samples from September to December of 2012, twice a week, from Six Mile Creek, a main tributary that flows into Lake Evergreen, the drinking water reservoir for Bloomington, Illinois. We also collected samples during storm events to compare with the phosphorus and phosphate amounts found in the biweekly base flow samples. Concentrations of phosphorus were measured in water samples using a spectrophotometer. Phosphorus concentrations are generally higher in the samples collected during storm events, suggesting that discharge and precipitation effect phosphorus concentrations. Base flow samples ranged from 0 to 45 microliters of phosphorus while samples collected during storm events ranged from 0 to 131 microliters.