The DOI Glen Canyon Leadership Team has directed Reclamation to carry out a High Flow Experiment from Glen Canyon Dam November 10-15, 2014. 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, 2014, and through November 9, 2014, the releases from Glen Canyon Dam will total approximately 16,736 acre-feet per day. Hourly and daily average releases from Glen Canyon Dam for November 1-9 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 9,000 cfs during the daytime hours and 6,500 cfs during the nighttime hours of midnight to 5:00 a.m..
During November 10-15, releases from Glen Canyon Dam will be made according to the hourly schedule described in the file attached to this notification. This schedule will be followed during the High Flow Experiment and shows the average hourly releases from Glen Canyon Dam that should occur during the High Flow Experiment. Note that the schedule shows power plant capacity releases of approximately 22,500 cfs. It is understood that the actual plant capacity with seven units running and 40 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, the required 27 MW of system reserves will not be maintained by Glen Canyon Dam and will be moved to other CRSP generation facilities. During the days prior to, and after the High Flow Experiment, the required 27 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 16,736 acre-feet per day. Beginning November 15, 2014 at 1400 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 9,000 cfs during the daytime hours and 6,500 cfs during the nighttime hours of midnight to 5:00 a.m. The scheduled release volume for November 2014 including the High Flow Experiment is approximately 770,000 acre-feet.
The release volume for December is expected to be approximately 865,000 acre-feet with daily fluctuations between approximately 9,500 and 17,500 cfs. The release volume for January is expected to be about 865,000 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).
The above update courtesy of Katrina Grantz, Bureau of Reclamation
River Runners for Wilderness has posted a map of the Grand Canyon with flow levels and dates here: https://rrfw.org/sites/default/files/2014_map_of_Grand_Canyon.jpg
and the Glen Canyon Dam release schedule here:
https://rrfw.org/sites/default/files/glen_schedule_10-29-2014.pdf