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Water Supply

  • Masonry Pool. The photo was taken on April 13, 2014 by Lloyd Buster.

April 15, 2014

Conditions and Outlook

Our overall water supply situation and outlook is good as we head into the spring reservoir refill season.

Last week, 0.94 inches and 1.16 inches of precipitation were recorded in our Cedar and South Fork Tolt River watersheds, respectively. Snowpack is close to but remains below the long term average for this time of the year. Snowpack accumulation in our watersheds typically peaks around the first week of April. Last week the snowpack for water supply started showing signs of melting off into our reservoirs.

Chester Morse Lake at the Overflow Dike is at elevation 1557.4 feet, about 2.4 feet higher than last week, and about 2.6 feet above its long term average (based on the years 1989 to 2005). Masonry Pool Reservoir at Masonry Dam is at elevation 1557.4 feet, about 2.5 feet higher than last week, and about 3.9 feet above its long term average. The South Fork Tolt Reservoir at the South Fork Tolt Dam is at elevation 1760.5 feet, about 0.3 feet lower than last week, and about 0.9 feet above 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 103 mgd. That is more than the 100 mgd consumed during the same period last year, and less than the average of 116 mgd used during the same period over the years 1999-2008.

Summer-run steelhead spawning should be nearly complete in the upper reaches of the South Fork Tolt River. Winter-run steelhead are spawning in the North Fork, mainstem and lower two miles of the South Fork Tolt River. Winter-run steelhead, resident and adfluvial trout continue to spawn in the Cedar system.

The emergence of young Chinook salmon from their redds in the Cedar River should be nearly complete. The emergence of young sockeye salmon is expected to continue through mid-May in the Cedar. In the South Fork Tolt River, the emergence of young Chinook and pink salmon should be nearly complete. Young coho continue to emerge from their redds in both systems. 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