Students of the Ocean Research College Academy (ORCA), an early college program through Everett Community College, have monitored bacteria data near Everett, Washington where the Snohomish River meets the Possession Sound since 2004. Used as an indicator of fecal contamination, Escherichia coli (E. coli) are found in the intestinal tract of humans and other homeothermic animals. This study investigates the spatial and temporal trends of E. coli levels at three sites within the Possession Sound between 2014-2019 in order to better elucidate the ecosystem’s health and potentially negative anthropogenic influences. Variation in coliform levels were analyzed with regard to physical and chemical factors such as tidal stage, depth, the Snohomish River discharge, salinity, temperature, dissolved oxygen, pH, and point sources including combined sewer outflows and storm drains. Water samples were collected with a Niskin bottle while a YSI 650 CTD or a YSI EXO Sonde was utilized to measure salinity, temperature, dissolved oxygen, and pH for each of the samples. ORCA students followed the Coliscan® Easygel® Protocol for inoculation, incubation and quantification. Data were reported as colonies of E. coli per 100 mL of water. Preliminary results show that E. coli levels have a seasonal correlation with river discharge, increasing in the fall, winter, and spring months when river discharge spikes. Coliform levels are higher at the halocline than at the surface or near-deep. Further sampling at additional upriver sites will demonstrate more sources of E. coli data. The results of this study will provide a foundation for understanding the fluctuations in the spatial and temporal trends of E. coli levels within the Possession Sound in order to better assess threats to the ecosystem health.