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Current Water Supply Conditions and Outlook

  • Masonry Pool. This photo was taken January 18, 2015 by Mark Hopf.

January 22, 2015

Supply Outlook

Our overall water supply situation and outlook is good.

Last week, 4.06 inches and 2.47 inches of precipitation were recorded in our Cedar and South Fork Tolt River watersheds, respectively. While snowpack is below the long term average for this time of the year, we have almost three months of winter left for snow to accumulate. We will be carefully watching how the snowpack builds throughout the remaining part of the snow season and we plan to hold water levels in our reservoirs above normal levels while staying within winter season flood management levels.

Chester Morse Lake at the Overflow Dike is at elevation 1555.8 feet, about 0.9 feet lower than last week, and about 5.0 feet above its long term average (based on the years 1989 to 2005). Masonry Pool Reservoir at Masonry Dam is at elevation 1555.7 feet, about 0.9 feet lower than last week, and about 8.7 feet above its long term average. The South Fork Tolt Reservoir at the South Fork Tolt Dam is at elevation 1759.7 feet, about 0.6 feet lower than last week, and about 6.0 feet above its long term average. Water releases from reservoir storage are actively being managed for water supply, fish habitat, hydropower and flood management objectives for both the Cedar and South Fork Tolt Rivers.

Water consumption for the previous seven days averaged approximately 101 mgd. That is less than the 102 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.

Sockeye and Chinook salmon completed spawning in the mainstem Cedar River by the end of December. Juvenile sockeye and Chinook salmon have begun to emerge from redds spawned early in the spawning period and these young fish will use the river margins to rear. Cedar River Coho salmon peak spawning is usually in December. Cedar Coho will continue to spawn in the Cedar River through the end of February. Young coho, steelhead and trout that emerged in 2014, are rearing in the Cedar at this time.

Tolt summer-run steelhead move into the upper reaches of the South Fork Tolt River during the summer and fall where they wait to spawn during the following winter and spring. At this time, early spawning steelhead in the population have begun to construct redds. These early redds will start to produce emerging fry in April. Adult summer steelhead will continue to spawn into the month of April so protection against redd scour and juvenile stranding are important. Young steelhead and coho that emerged in 2014 are currently rearing in the South Fork Tolt.

View Current Water Supply Graphs (pdf)

Related links

Landsburg Mitigation
Water Sources and Treatment