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Current Water Supply Conditions and Outlook

  • Chester Morse Lake Outlet Channel. This photo was taken October 12, 2014 by Mark Hopf.

October 14, 2014

Supply Outlook

Our overall water supply situation and outlook is good.

Last week, 0.67 inches and 1.07 inches of precipitation were recorded in our Cedar and South Fork Tolt River watersheds, respectively.

Chester Morse Lake at the Overflow Dike is at elevation 1550.4 feet, about 0.5 feet lower than last week, and about 4.7 feet above its long term average (based on the years 1989 to 2005). Masonry Pool Reservoir at Masonry Dam is at elevation 1531.4 feet, about 16.0 feet lower than last week, and about 2.5 feet above its long term average. The South Fork Tolt Reservoir at the South Fork Tolt Dam is at elevation 1732.2 feet, about 1.5 feet lower than last week, and about 8.5 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.

Water consumption for the previous seven days averaged approximately 113 mgd. That is more than the 105 mgd consumed during the same period last year, and less than the average of 128 mgd used during the same period over the years 1999-2008.

Sockeye and Chinook salmon are spawning in the Cedar River. Most Cedar River sockeye spawn between mid-September and mid-December, with peak activity usually occurring during the second half of October. Most Cedar River Chinook spawn between mid-September and mid-November, with peak activity usually in early to mid-October. Chinook are also spawning in the Tolt River system. These fish typically spawn in mainstem, North Fork and lower two miles of the South Fork Tolt River through mid-November.

Young steelhead and coho salmon are rearing in the Cedar and South Fork Tolt rivers. Resident and adfluvial trout are rearing in the Cedar.

Adult summer-run steelhead continue to return to the Tolt River basin. Most of these returning fish move into the upper reaches of the South Fork Tolt River where they hold through the summer and fall, then spawn during the following winter and spring.

View Current Water Supply Graphs (pdf)

Related links

Landsburg Mitigation
Water Sources and Treatment