Water Supply Conditions
Below are current supply conditions for Seattle's regional water system.
September 24, 2023
Last week, the 7-day precipitation totals for the period 9/18/2023 through 9/25/2023 were 2.8 inches and 2.0 inches in our Cedar River and South Fork Tolt (SF Tolt) River watersheds, respectively.
Chester Morse Lake at the Overflow Dike was at elevation 1547.7 feet, about 0.8 feet lower than last week, and about 2.1 feet below its long-term average (based on the years 1990 to 2019). The South Fork Tolt Reservoir at the South Fork Tolt Dam was at elevation 1724.9 feet, about 0.7 feet lower than last week, and about 15.9 feet below its long-term average. Water releases from reservoir storage are actively being managed for water supply, fish habitat and flood management objectives for both the Cedar and South Fork Tolt Rivers.
Water consumption for the previous seven days averaged approximately 131 million gallons per day (mgd). That is 21 mgd less than the 157 mgd consumed during the same period last year, and 4 mgd more than the average of 127 mgd used during the same period over the years 2010-2019.
After an unusually dry summer and an extended seasonal outlook for a dry fall, Seattle is concerned about having sufficient water for people and fish through the end of the year. To help stretch our water supply until the return of sustained fall rains, Seattle Public Utilities activated the Voluntary Stage of our Water Shortage Contingency Plan. While we always ask customers to use water wisely, we are asking customers to voluntarily use less water than they normally would. For practical tips and information on how to save water this year, please visit www.savingwater.org.