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Water Supply

  • Masonry Pool. The photo was taken on May 12, 2013 by Lloyd Buster.

May 14, 2013

Conditions and Outlook

Our overall water supply situation and outlook is good.

Last week, 0.79 inches and 1.46 inches of precipitation were recorded in our Cedar and South Fork Tolt River watersheds, respectively. Snowpack for water supply is above the long term average for this time of the year and is melting off into our reservoirs during the spring reservoir refill season.

Chester Morse Lake at the Overflow Dike is at elevation 1559.6 feet, about 1.9 feet higher than last week, and about 1.3 feet above its long term average (based on the years 1989 to 2005). Masonry Pool Reservoir at Masonry Dam is at elevation 1559.5 feet, about 1.9 feet higher than last week, and about 2.0 feet above its long term average. The South Fork Tolt Reservoir at the South Fork Tolt Dam is at elevation 1761.1 feet, about 2.5 feet higher than last week, and about 0.4 feet below 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 129 mgd. That is more than the 113 mgd consumed during the same period last year, and more than the average of 126 mgd used during the same period over the years 1999-2008.

Summer-run steelhead have completed spawning in the upper reaches of the South Fork Tolt River; winter-run steelhead continue to spawn in the North Fork Tolt, mainstem and lower 1.6 miles of the South Fork Tolt River. Young summer-run steelhead should be starting to emerge from their redds. Winter-run steelhead, resident and adfluvial trout continue to spawn in the Cedar system.

The emergence of young Chinook salmon from their redds is complete in the Cedar and South Fork Tolt rivers. The emergence of young sockeye is nearly complete in the Cedar River. Young coho continue to emerge in the Cedar and Tolt. Most sockeye emerge between late January and mid-May. Most coho emerge between early March and early June. Salmon eggs and alevins will continue to incubate in the gravels of the Cedar and South Fork Tolt rivers through late May. Steelhead eggs and alevins will incubate through late July.

View Current Water Supply Graphs (pdf)

Tips for customers

  • Wash full loads of clothes.
  • Fix leaking toilets and faucets.
  • Wash your vehicle at locations that recycle their water.
  • Turn off running water in bathrooms or kitchen sinks.
  • Check out the Saving Water Partnership’s Plant List (pdf) for water-wise suggestions.
  • Visit the Saving Water Partnership or call (206) 684-SAVE (7283) for more water-wise tips.

Related links

Landsburg Mitigation
Cedar River Watershed
Tolt River Watershed
Water Shortage Contingency Plan