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Current Water Supply Conditions and Outlook

  • Masonry Pool. This photo was taken July 13, 2014 by Lloyd Buster.

July 15, 2014

Supply Outlook

Our overall water supply situation and outlook is good.

Last week, 0.00 inches and 0.00 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 1560.9 feet, about 1.2 feet lower than last week, and about 3.0 feet above its long term average (based on the years 1989 to 2005). Masonry Pool Reservoir at Masonry Dam is at elevation 1560.8 feet, about 1.3 feet lower than last week, and about 4.0 feet above its long term average. The South Fork Tolt Reservoir at the South Fork Tolt Dam is at elevation 1756.4 feet, about 2.2 feet lower than last week, and about 2.3 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 188 mgd. That is more than the 167 mgd consumed during the same period last year, and more than the average of 186 mgd used during the same period over the years 1999-2008.

This year’s return of adult sockeye salmon is passing through the Ballard Locks facilities. On June 12, biologists from the Muckleshoot Indian Tribe and Washington Department of Fish and Wildlife initiated formal data collection and daily estimates of the number of fish passing upstream. Based upon counts so far, WDFW is projecting that this year’s sockeye return will be well below the pre-season forecast.

The emergence of young coho salmon (fry) from their redds is complete in the Cedar and South Fork Tolt rivers. After emerging, young coho usually rear for one year in freshwater prior to migrating to sea. Young steelhead continue to emerge from their redds in the Tolt basin. Steelhead fry are expected to continue to emerge through late July. These young steelhead typically rear for two years in freshwater before migrating to sea.

Adult summer-run steelhead are returning to the Tolt River basin. Most of these fish will move into the upper reaches of the South Fork Tolt 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