High Flow Experiment to Begin November 11

The Department of Interior Glen Canyon Leadership Team has directed the Bureau of Reclamation to carry out a High Flow Experiment from Glen Canyon Dam November 11-16, 2013. This notification describes the operations of Glen Canyon Dam in November for the days prior to, during, and after the High Flow Experiment.

Beginning on November 1, 2013, and through November 10, 2013, the releases from Glen Canyon Dam will total approximately 14,008 acre-feet per day. Hourly and daily average releases from Glen Canyon Dam for November 1-10 will be scheduled through Western Area Power Administration to be consistent with the Glen Canyon Dam Operating Criteria (Federal Register, Volume 62, No. 41, March 3, 1997) and to also achieve, as nearly as is practicable, this daily release volume. Releases are anticipated to fluctuate between approximately 8,000 cubic feet per second (cfs) during the daytime hours and 5,000 cfs during the nighttime hours of midnight to 7:00 a.m.

During November 11-16, releases from Glen Canyon Dam will be made according to the hourly schedule described at http://www.usbr.gov/uc/water/crsp/cs/images/2013HFE_hydrograph.JPG.

The above link shows the scheduled hourly releases from Glen Canyon Dam during the High Flow Experiment. Note that the schedule shows power plant capacity releases of approximately 22,200 cfs with full bypass increasing the total release up to approximately 37,000 cfs. The 37,200 cfs will be maintained till Friday November 15.  It is understood that the actual plant capacity with seven units running and 40 megawatts (MW) of system regulation may be slightly more or less than this estimate.

During all days of November, including during the High Flow Experiment, 40 MW of system regulation will be maintained at Glen Canyon Dam. During the High Flow Experiment, 41 MW of system reserves will be moved off of Glen Canyon Dam. During the days prior to and after the HFE, the usual 41 MW of system reserves will be maintained at Glen Canyon Dam.

After the High Flow Experiment, releases will return to a daily total of approximately 14,008 acre-feet per day.  Beginning November 16, 2013 at 1500 hours, hourly and daily average releases from Glen Canyon Dam will resume being scheduled through Western Area Power Administration to be consistent with the Glen Canyon Dam Operating Criteria (Federal Register, Volume 62, No. 41, March 3, 1997) and to also achieve, as nearly as is practicable, this daily release volume. Releases are anticipated to fluctuate between approximately 8,000 cfs during the daytime hours and 5,000 cfs during the nighttime hours of midnight to 7:00 a.m. The scheduled release volume for November 2013 including the High Flow Experiment is approximately 700,000 acre-feet.

The release volume for December is expected to be 600,000 acre-feet, with fluctuations between approximately 6,000 cfs and 12,000 cfs. The release volume for January is expected to be 800,000 acre-feet. Releases for December and January will be confirmed with a subsequent notification toward the end of November.

This notification supersedes all previously issued notifications and is current until a new notification is issued. All times identified in this notification and attached schedule are local time (MST).

This update courtesy of Katrina Grantz, Bureau of Reclamation