Seattle Public Utilities Mami Hara, Director

Current Water Supply Conditions

  • Masonry Pool ReservoirMasonry Pool Reservoir– This photo was taken on October 16, 2016 by Aaron Erman.

October 18, 2016

Another series of wet weather systems hit the Pacific Northwest region last week as the seasonal fall rains have returned in earnest. Last week 5.57 inches and 5.60 inches of precipitation were recorded in our Cedar River and South Fork Tolt River watersheds, respectively.

Chester Morse Lake at the Overflow Dike is at elevation 1551.3 feet, about 2.3 feet higher than last week, and about 5.6 feet above its long term average (based on the years 1989 to 2005). Masonry Pool Reservoir at Masonry Dam is at elevation 1534.3 feet, about 6.0 feet higher than last week, and about 5.5 feet above its long term average. The South Fork Tolt Reservoir at the South Fork Tolt Dam is at elevation 1742.8 feet, about 3.5 feet higher than last week, and about 2.2 feet above its long term average. Water releases from reservoir storage are actively being managed for water supply, hydropower, fish habitat and flood management objectives for both the Cedar and South Fork Tolt Rivers.

Water consumption for the previous seven days averaged approximately 107 million gallons per day (mgd). That is less than the 108 mgd consumed during the same period last year, and less than the average of 120 mgd used during the same period over the years 1999-2014.

Related links

Current water supply graphs (pdf)

Related links

Landsburg Mitigation
Water Sources and Treatment