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The City of Portland, Oregon

Portland Water Bureau

From forest to faucet, we deliver the best drinking water in the world.

Customer Service: 503-823-7770


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Seasonal Water Supply Planning

  • Bull Run Reservoirs Store 9.9 Billion Gallons of Drinking Water.

  • Portland's secondary source of high quality groundwater can be used to supplement summer demand when needed

Each year, the Portland Water Bureau develops a Seasonal Water Supply Augmentation and Contingency Plan. This plan evaluates the availability of water from the Bull Run and groundwater sources, projected weather forecasts, and water demands to guide management of the drinking water system. Between careful management and the region’s strong conservation efforts, the Water Bureau is prepared to meet the range of potential supply and demand conditions that could occur in the Portland water system this season.

The dry spring weather and periods of above average temperatures has resulted in an unusually early start to reservoir drawdown for 2019. The Portland Water Bureau will continue to monitor weather forecasts and supply conditions to make the necessary decisions to ensure there is sufficient water to meet customer needs.

October 17, 2019 Update: The dry spring weather of 2019 resulted in an unusually early start to reservoir drawdown. The early start to drawdown along with available long-term weather forecasts predicting a dry summer resulted in the Portland Water Bureau supplementing the Bull Run drinking water supply with groundwater from the Columbia South Shore Well Field from July 10 to August 27, at an approximate blend of 25-35% groundwater to Bull Run. As a result of recent rains, there is currently approximately 4.5 billion gallons of usable storage in the Bull Run reservoirs. This along with the availability of additional groundwater if needed, is anticipated to be sufficient to meet system needs until the Bull Reservoirs return to full capacity. 

The graph below shows the usable storage in the Bull Run reservoirs for 2019 (blue) compared to the average level (green), and 2015 (yellow) and 2018 (orange), recent hot dry summers.

Graph of usable Storage for 2019 compared to 2018, 2015 and average

Drawdown Curve

August 6, 2019

Demand Curve

August 6, 2019

Water Efficiency Information

Information about ways to use water wisely.