Water Supply and Treatment

Where does your drinking water come from?

Lake Whatcom is the drinking water source for over 100,000 people, which is approximately half of all Whatcom County residents.  Water is provided by: 

Water flows into Lake Whatcom from two main sources:


How does your drinking water get from the lake to your tap?

Drinking water is withdrawn from two major intake structures in the lake. 

The City of Bellingham withdraws water from Basin 2 through a 1,200-foot wooden pipeline that leads to Whatcom Falls Park.  At the park, the water first flows through a screenhouse then to the treatment plant.  The city's treatment plant is capable of producing 24 million gallons of drinking water per day and serves residents of Bellingham as well as five neighboring water districts and one tribal nation.

The Lake Whatcom Water and Sewer District withdraws water out of Basin 3 to serve residents of Sudden Valley, Geneva, and portions of North Shore and South Bay. The  District's treatment process is similar to that of the City of Bellingham but uses four multi-media filters and reaches a maximum output of 50,100 gallons per day.

What happens to your wastewater?

Sewers were first installed throughout the developed areas of Bellingham in 1892. These original sewers collected both sewage and rainwater and discharged them into Whatcom Creek and Bellingham Bay. Most of these early sewers are still in use. The ones carrying sewage are now separate from those carrying stormwater and send their flows directly to the wastewater treatment plant.  

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