Water Supply Conditions
The current supply conditions for Seattle's regional water system.
September 16, 2024
Last week, the 7-day precipitation totals for the period 9/9/2024 through 9/15/2024 were 1.23 inches and 0.69 inches in our Cedar River and South Fork (S.F.) Tolt River watersheds, respectively.
Chester Morse Lake at the Overflow Dike was at an elevation of 1550.6 feet, about 0.6 feet lower than last week, and about 0.1 foot above its long-term average (based on the years 1990 to 2019). The S.F. Tolt Reservoir at the S.F. Tolt Dam was at an elevation of 1744.6 feet, about 1.6 feet lower than last week, and about 2.6 feet above 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 136 million gallons per day (mgd). That is about 14 mgd less than the 150 mgd consumed during the same period last year, and less than the 139 mgd used during the same period over the years 2010-2019.
Based on current conditions and forecasts, Seattle anticipates the regional water system will have sufficient water supply for people and fish this summer. As always, we continue to ask customers to use water wisely. For information about ways to save water, visit www.savingwater.org.
Note:
Regular readers may notice changes to the presentation of the Water Supply Synopsis. These changes bring components of this report into compliance with Web Content Accessibility Guidelines and into line with the City of Seattle style guide. These changes to plot color schemes and to plot layout make it easier for readers with visual impairments to read these charts.
While the presentation looks different, the information in this week’s water supply synopsis and the methods used to calculate these values are exactly the same as they have been in previous weeks.