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Current Water Supply Conditions and Outlook

  • Masonry Pool. This photo was taken June 28, 2015 by Mark Hopf.

July 1, 2015

Supply Outlook

Our current water supply outlook is good. However, the unusually warm and dry weather we’ve had since May has caused inflows into our water supply reservoirs to be quite low for this time of year. Water use is also up significantly compared to typical amounts over the same period. We are monitoring the situation closely and carefully. Last week, 0.04 inches and 0.21 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 1553.7 feet, about 2.2 feet lower than last week, and about 5.7 feet below its long term average (based on the years 1989 to 2005). Masonry Pool Reservoir at Masonry Dam is at elevation 1553.3 feet, about 2.5 feet lower than last week, and about 5.2 feet below its long term average.

The South Fork Tolt Reservoir at the South Fork Tolt Dam is at elevation 1747.7 feet, about 2.5 feet lower than last week, and about 13.1 feet below its long term average. Water releases from reservoir storage are actively being managed for water supply and fish habitat management objectives for both the Cedar and South Fork Tolt Rivers. Streamflows in both the South Fork Tolt River and Cedar River are being held slightly above guaranteed flows for this time of the year and are providing full protection for incubating salmon and steelhead trout.

Water consumption for the previous seven days averaged approximately 192 mgd. That is more than the 150 mgd consumed during the same period last year, and more than the average of 169 mgd used during the same period over the years 1999-2008.

View Current Water Supply Graphs (pdf)

Related links

Landsburg Mitigation
Water Sources and Treatment