The Belleisle Watershed covers approximately 37,000 ha stretching from Pearsonville to Lower Kars on the Northern side and from Mercer Settlement to Kingston Corner on the Southern side. The Belleisle Bay itself is approximately 24 Km2 freshwater offshoot of the Saint John River that is slightly effected by tide. Belleisle Bay has 20 named tributaries feeding into it.

The BWC has assessed and monitored many of the tributaries have since 2013. These stream assessments examine the water quality, fish habitat, and riparian (stream side) health of numerous sites along the watercourse for more information, please see our ETF Reports or the project section of the website.

The Belleisle Watershed is frequently used for recreational activities (swimming, boating, and fishing) by the residents and the many cottage owners that live within the rural communities that make up the watershed. Therefore the water quality of the bay and streams is important to many community members to ensure these activities can continue for future generations.

The most notable industries within the watershed are agriculture and forestry. Both of these industries can have impacts to the water quality and fish habitat such as sedimentation and nutrient runoff. Since 2017, the BWC has conducted monitoring of water quality in the Bay. Results of these efforts indicate the Bay has good water quality overall but faces challenges from Cyanobacteria Blooms, Development and Climate Change.