The City owns and operates a regional water treatment plant on the east side of the Skagit River near Mount Vernon. The plant was built in 2013 on the site of the previous plant.
Features include a ballasted sedimentation system for pre-treatment, eight filters, an above ground clearwell, and a high-service pump station. The plant has the capacity to produce 42 million gallons of water per day, expandable to 55 million gallons per day. It serves approximately 56,000 residential, commercial and industrial customers.
Water from the plant is pumped through 24-inch and 36-inch transmission lines serving western Skagit County and northern Island County. In addition to the City of Anacortes, the plant provides water to the City of Oak Harbor, which supplies the Naval Air Station Whidbey Island; the Town of La Conner, which supplies Shelter Bay; the Swinomish Indian Tribal Community; Skagit Public Utility District #1; and the Marathon and Shell oil refineries.