Located in the Whidbey Basin, Possession Sound is a body of water within the Puget Sound that is directly influenced by the Snohomish River. Water runoff from rain events takes phosphorus from the soil and eroded rocks, and introduces it into the Snohomish River, which eventually travels into Possession Sound. Additionally, irrigation, agriculture, construction and other human influences on the environment affect the chemistry of the water. Students of the Ocean Research College Academy (ORCA), a Running Start program through Everett Community College, have been collecting water chemistry and nutrient data in Possession Sound for the past ten years. Our research group compiled data from previous years to study the relationship between phosphorus concentration and salinity. Salinity levels were determined by EXO Sonde or YSI 650 and water samples were captured with a Niskin bottle, which were sent to the University of Washington Marine Chemistry Laboratory for nutrient analysis. The data were collected at three different research stations. Two sites are located near the mouth of the Snohomish River and the Port of Everett, while the third is further south and not as directly impacted by the freshwater from the Snohomish River, however there is some freshwater impact due to storm drains near the data collection site. It was hypothesized that, higher phosphate levels would be found in lower salinity water nearest the Snohomish River. Over several years, we expected to see different patterns in phosphorus levels based on Snohomish River discharge. Data and findings from this research project will aid in our understanding on our Spring Quarter research project, which will focus on plankton concentrations in the Possession Sound.