What’s seasonal supply planning?
Each year, we develop a plan to make sure we can provide enough water to Portlanders and nearby wholesale customers through the dry summer months. This seasonal water supply plan evaluates:
- How much water is available in the Bull Run Watershed and in our groundwater source, the Columbia South Shore Well Field
- Projected weather forecasts
- Overall demand for water
We use our seasonal plan to help us manage Portland’s drinking water system. Thanks to the Water Bureau’s careful planning, continuing investment in two high-quality water sources, and conservation efforts we are ready to meet Portland’s water needs this summer.
Learn more about our seasonal supply planning
Where does Portland’s water come from?
Portland’s primary drinking water source is the Bull Run Watershed. Even though the watershed is near Mount Hood, it doesn’t receive runoff or snowmelt from the mountain. Instead, abundant rain in the watershed during the wet season (late fall through spring) fills two reservoirs. These reservoirs store the water Portland needs to get through the dry summer. (You may be surprised to learn that snowpack levels in the Bull Run Watershed don’t have much influence on summer water supply. The amount of precipitation in April, May, and June has the most impact.)
Some summer seasons are particularly hot and dry in the Portland area. We keep monitoring reservoir levels, water use, and the weather throughout the summer. If needed, we can use our secondary source, groundwater from the Columbia South Shore Well Field, to supplement the water from Bull Run. With these two high-quality water sources, we expect to have enough water for the summer season.
How can Portlanders use water wisely?
As stewards of Portland’s drinking water system, we are committed to clean, safe, abundant water for every Portlander—all year round. This summer, you can do your part by using water wisely. Our Water Efficiency team can help you save water in your home and outdoors. We also offer rebates and free water-saving devices for your home.