FBE performed water quality sampling and analysis on the Pemaquid River for the Town of Bristol in 2018 and 2019 in collaboration with the Bristol Shellfish Committee and Pemaquid Watershed Association (now Coastal Rivers Conservation Trust). The Pemaquid River and its estuary are listed as impaired by the Maine Department of Environmental Protection (DEP) due to elevated fecal indicator bacteria, and portions of the river have suffered from shellfishing closures. Following investigative sampling by DEP in 2017, FBE sampled freshwater tributaries on the Pemaquid River and its estuary in 2018 to identify possible sources of fecal contamination contributing to the impairment. The 2018 results and further tributary bracket sampling and microbial source tracking in 2019 indicated potential septic system contamination, agriculture contamination sources, and wildlife contribution. FBE has continued to provide technical expertise to the Town and stakeholders to guide further efforts in eliminating fecal contamination in the watershed. In 2020, the Town of Bristol is working with FBE to perform a Septic System Vulnerability Assessment to identify septic systems that may be at risk of malfunctioning or failure and could be sources of fecal contamination to downstream waterbodies.