Topic: UPDATE Canyon Creek and South Yuba Flows
|Posted: May 4, 2010Post Subject: UPDATE Canyon Creek and South Yuba Flows
|Releases Postponed One Week: Due to changing operational conditions NID is altering the releases that will be used as study flows.|
On Saturday, May 15 through Monday, May 17 NID will release 200 CFS through the power house below Bowman Dam, resulting in 200 cfs plus accretion on lower Canyon Creek. It is possible that the release will continue past Monday.
Provisionally, Saturday May 22 through Monday, May 24 the release below Bowman into Canyon Creek will be increased to 300 cfs.
The May 22 through May 24 300 cfs release from Bowman into Canyon Creek is contingent on water being on the gates at Spaulding, enabling a release of 250 cfs out of Spaulding into the South Yuba on May 22 and 23.
The combined releases from Bowman and Spaulding will provide for study flows in all of the South Yuba reaches below the Canyon Creek confluence.
Flow Study Surveys
If you paddle any reach of Canyon Creek or the South Yuba in the next several weeks, please go to http://www.zoomerang.com/survey/web2297AJ8Q9ZL and fill out a boater survey. Survey information will be important in determining future flows in these reaches.
The contingency is the weather, particularly temperature above Spaulding, which will drive how fast the snow comes off and fills Spaulding. We will provide an update next Monday, May 10.
Opportunistic Nature of Study Flows
NIDís most recent snow survey indicates 118% of normal snow pack. The next PG&E survey will likely show a similar snow pack. Both Bowman and Spaulding will spill, and the above releases are primarily driven by operational management of spill. For example, the 200 cfs and 300 cfs releases out of Bowman Lake will generate power with water that would otherwise spill.