Difference between revisions of "The 2018 Fall HFE"

Revision as of 15:11, 19 November 2018

High Flow Experiment- 2018

2018 High Flow Experiment Snapshot

Sediment Conditions

Fall Accounting Period

• Paria input (Jul 1 - Sept 21): 709,000
• Accumulated in Upper Marble Canyon (Jul 1 - Sept 4, lower bound) = 238,000
• Accumulated in Lower Marble Canyon (Jul 1 - Sept 4, lower bound) = 84,000
• Available for HFE: 238,000 + 84,000 = 322,000

HFE Transport

• Paria input (Nov 5 - 10):
• Evacuated from Upper Marble Canyon (Nov 5 - 10, lower bound) =
• Evacuated from Lower Marble Canyon (Nov 5 - 10, lower bound) =
• Left over in Marble Canyon after HFE (Nov 5 - 10):

Winter Accounting Period

• Paria input (Nov 11 to Apr 1):
• Evacuated from Upper Marble Canyon (Dec 1 to Apr 1, lower bound) =
• Evacuated from Lower Marble Canyon (Dec 1 to Apr 1, lower bound) =
• Available for spring HFE:

HFE Details

Schedule & Duration

• Nov. 5 - 6:00 a.m. begin upramp to powerplant capacity (~23,100 cfs) [7 generation units]
• Nov. 5 - 11:00 a.m. open bypass tubes, reach full bypass at 2:00 p.m.
• Nov. 8 - 9:00 a.m. end of bypass
• Nov. 8 - 3:00 p.m. end of High Flow Experiment
• Total duration: 3 days & 10 hours; 2 ½ days at peak release (60 hours)

Ramp Rates

• Ramp up: 4,000 cfs/hr from 6,500 - 23,100 cfs, then 3,750 cfs/hr to peak (38,100 cfs)
• Ramp down: 1,875 cfs/hr from 38,100 – 23,100 cfs, then 2,500 cfs/hr to 9,000 cfs

https://www.usbr.gov/uc/rm/gcdHFE/

• Maximum total release: 38,100 cfs
• Powerplant capacity: 23,100 cfs
• River outlet tubes: 15,000 cfs
• Hydropower generation units available: 7 (one unit off-line for replacement)
• River outlet tubes: 4

Releases and Lake Elevation

• Releases will range from 6,500 - 9,000 cfs prior to and after the HFE
• Lake elevation is projected to decrease by approximately 7 inches during the 3-day experiment

Costs

• Estimated costs to hydropower: $923,963
• Actual costs to hydropower: TBD
• Direct expenses for removal of concession assets: TBD

SUPPORTING DOCUMENTS

https://www.usbr.gov/uc/rm/gcdHFE/

• 2018 High Flow Experimental Release Decision Memorandum
• Final Tech Team Report: Recommendation to Implement a Fall 2018 High Flow Experiment at Glen Canyon Dam, November 5-8, 2018

COMPLIANCE

• News Release: Interior Initiates High-Flow Experiment at Glen Canyon Dam
• Media Advisory: High-Flow Experiment at Glen Canyon Dam

CONCERNS

• Angler's 2018 HFE deferral letter
• GCRMC response to HFE deferral request

ADDITIONAL

• AZ Central news article: Controlled flood of the Grand Canyon begins a four-day exercise on the Colorado River
• Lighted bypass tube video
• Colorado River Pearce Ferry Rapid After High Flow Release From Glen Canyon Dam