Difference between revisions of "GCDAMP Glen Canyon Dam"

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[[File:2016 Releases (1).jpg|600px]]
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[[File:LTEMPmonthlyvolumes.jpg|center|400px]]
  
 
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== '''Operations of Glen Canyon Dam''' ==  
 
== '''Operations of Glen Canyon Dam''' ==  
−
The Record of Decision (ROD) on the operation of Glen Canyon Dam was signed on October 9, 1996. It stipulated flows at Glen Canyon (via reference to the EIS(1)). A new operating criteria for Glen Canyon Dam was signed on February 24, 1997.
+
The [http://ltempeis.anl.gov/documents/docs/LTEMP_ROD.pdf '''LTEMP Record of Decision (ROD)'''] on the operation of Glen Canyon Dam was signed on December 15, 2016. It changed operations at Glen Canyon from the 1996 ROD that implemented the MLFF flow regime. <br>
  
−
According to the EIS, minimum flows of 8,000 cubic feet per second (cfs) during the day and 5,000 cfs at night were incorporated within the preferred alternative largely to maintaining the food base for the sport fishery (EIS, pg 223). The maximum flow of 25,000 cfs was imposed in order to conserve sediment in the Grand Canyon, especially in the Marble Canyon area. The maximum daily change limitation of 8,000 cfs (during “wet” months) was intended to benefit a variety of resources; sport fish, native fishes, recreation, riparian vegetation and habitat and cultural. The downramp limit of 1,500 cfs was mainly imposed to reduce the erosion of beaches (sand deposits) in the Marble Canyon reach due to rapid leaching of water in the sand (EIS, pg 204). The ROD and operating criteria include “emergency exception criteria” which continued over from “interim flows” as a recognition of the fact that the Glen Canyon Powerplant is connected to an electrical system. [https://www.wapa.gov/regions/CRSP/PlanProject/Pages/glen-canyon-operations.aspx]
+
'''Minimum flows:'''  [[File:LTEMP monthly volumes.png|right|500px]]
 +
*8,000 cfs between 7 a.m. and 7 p.m.
 +
*5,000 cfs between 7 p.m. and 7 a.m.
 +
'''Maximum non-experimental flows:''' 
 +
*25,000 cfs
 +
'''Daily range:'''
 +
*June–August: Equal to 10 × monthly volume (in kaf)
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*All other months: 9 × monthly volume (in kaf)
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*Daily range not to exceed 8,000 cfs
 +
'''Ramp rates:'''
 +
*4,000 cfs/hr up
 +
*2,500 cfs/hr down
  
−
== '''Operating tier for WY2017''' ==
 
−
The operating tier for water year 2017, established in August 2016, is the Upper Elevation Balancing Tier, with an initial water year release volume of 8.23 maf and the potential for an April 2017 adjustment to equalization or balancing releases.  Based on the current forecast, an April adjustment to balancing releases is projected to occur and Lake Powell is currently projected to release 9.0 maf in water year 2017.  This projection will be updated each month throughout the water year. [http://www.usbr.gov/uc/water/crsp/cs/gcd.html]
 
  
 
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! style="width=33%; background:#cedff2;" | [[TBD|---]]
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! style="width=33%; background:#cedff2;" | [http://www.usbr.gov/uc/water/crsp/cs/gcd.html Current Status] <br>
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! style="width=33%; background:#cedff2;" | [[TBD|---]]  
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! style="width=33%; background:#cedff2;" | [http://www.usbr.gov/uc/water/crsp/cs/gcd.html Current Operations]  
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! style="width=33%; background:#cedff2;" | [[TBD|---]]
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! style="width=33%; background:#cedff2;" | [http://www.usbr.gov/uc/water/crsp/cs/gcd.html Inflow Forecasts <br> and Model Projections]  
 
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! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3bfb1; text-align:left; color:#000; padding:0.2em 0.4em;">Updates</h2>
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! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3bfb1; text-align:left; color:#000; padding:0.2em 0.4em;"> Updates </h2>
 
|-
 
|-
 
|style="color:#000;"|
 
|style="color:#000;"|
  
−
[[File:2017MonthlyVolumes.jpg|600px]] [https://www.usbr.gov/uc/rm/amp/twg/mtgs/17jan26/A4_Davidson.pdf]
+
== '''Glen Canyon Monthly Operational Call''' ==
 +
The DOI also will conduct monthly Glen Canyon Dam operational coordination meetings or calls with the DOI bureaus (USGS, NPS, FWS, BIA, and Reclamation), WAPA, AZGFD, and representatives from the Basin States and the UCRC. Each DOI bureau will provide updates on the status of resources and dam operations. In addition, WAPA will provide updates on the status of the Basin Fund, projected purchase power prices, and its financial and operational considerations. These meetings or calls are intended to provide an opportunity for participants to share and obtain the most up-to-date information on dam operational considerations and the status of resources (including ecological, cultural, Tribal, recreation, and the Basin Fund). One liaison from each Basin State and from the UCRC will be allowed to participate in the monthly operational coordination meetings or calls. [https://ltempeis.anl.gov/documents/docs/LTEMP_ROD.pdf]
 +
 
 +
*[[Media:202411_Information.pdf| November 2024 Operations call]]
 +
*[[Media:202410_Information.pdf| October 2024 Operations call]]
 +
*[[Media:202409_Information.pdf| September 2024 Operations call]]
 +
*[[Media:202408_Information.pdf| August 2024 Operations call]]
 +
*[[Media:202407_Information.pdf| July 2024 Operations call]]
 +
*[[Media:202406_Information.pdf| June 2024 Operations call]]
 +
*[[Media:202405_Information.pdf| May 2024 Operations call]]
 +
*[[Media:202404_Information.pdf| April 2024 Operations call]]
 +
*[[Media:202403_Information.pdf| March 2024 Operations call]]
 +
*[[Media:202402_Information.pdf| February 2024 Operations call]]
 +
*[[Media:202401_Information.pdf| January 2024 Operations call]]
 +
*[[Media:202312_Information.pdf| December 2023 Operations call]]
 +
*[[Media:202311_Information.pdf| November 2023 Operations call]]
 +
*[[Media:102023_Information.pdf| October 2023 Operations call]]
 +
 
 +
[[Archived Glen Canyon Monthly Operations Call slides]]
 +
 
 +
|-
 +
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b0bf; text-align:left; color:#000; padding:0.2em 0.4em;"> Critical Reservoir Elevations at Powell and Mead</h2>
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|-
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|style="color:#000;"|
 +
 
 +
[[File:Glen_Canyon_critical_elevations.png|center|600px]]
 +
 
 +
 
 +
[[File:Mead_critical_elevations.png|center|600px]]
  
 
== '''USBR Monthly/Annual Reports''' ==
 
== '''USBR Monthly/Annual Reports''' ==
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*[https://www.usbr.gov/uc/water/rsvrs/ops/aop/index.html Annual Operating Plans for Colorado River reservoirs]
 
*[https://www.usbr.gov/uc/water/rsvrs/ops/aop/index.html Annual Operating Plans for Colorado River reservoirs]
  
−
== '''Report to Congress Regarding Operations of Glen Canyon Dam''' ==
+
== '''Report to Congress Regarding Operations of Glen Canyon Dam'''[https://www.usbr.gov/uc/DocLibrary/reports.html] ==
−
 
+
*[https://www.usbr.gov/uc/DocLibrary/Reports/GlenCanyonDam/20210500-GlenCanyonDam-ReportCongress-2020-2021-508-UCRO.pdf Report to Congress - Water Year 2020-2021 ]
 +
*[https://www.usbr.gov/uc/DocLibrary/Reports/GlenCanyonDam/20210400-GlenCanyonDam-ReportCongress-2019-2020-508-UCRO.pdf Report to Congress - Water Year 2019-2020]
 +
*[https://www.usbr.gov/uc/DocLibrary/Reports/GlenCanyonDam/20200600-GlenCanyonDam-ReportCongress-2018-2019-508-UCRO.pdf Report to Congress - Water Year 2018-2019]
 +
*[https://www.usbr.gov/uc/DocLibrary/Reports/GlenCanyonDam/20180800-GlenCanyonDam-ReportCongress-2017-2018-508-UCRO.pdf Report to Congress - Water Year 2017-2018]
 +
*[https://www.usbr.gov/uc/envdocs/reports/GCDam/GC-Report-to-Congress2016-2017.pdf Report to Congress - Water Year 2016-2017 ]
 
*[[Media:Years 2015-16 GC Report to Congress FINAL.pdf| 2015-2016 Report to Congress ]]
 
*[[Media:Years 2015-16 GC Report to Congress FINAL.pdf| 2015-2016 Report to Congress ]]
−
*[http://www.usbr.gov/uc/envdocs/reports/GCDam/GC-Report-to-Congress2013-2014.pdf 2014-2015 Report to Congress ]
+
*[https://www.usbr.gov/uc/DocLibrary/Reports/GlenCanyonDam/20150800-GlenCanyonDam-ReportCongress-2014-2015-508-UCRO.pdf 2014-2015 Report to Congress ]
 
*[http://www.usbr.gov/uc/envdocs/reports/GCDam/GC-Report-to-Congress2013-2014.pdf 2013-2014 Report to Congress ]
 
*[http://www.usbr.gov/uc/envdocs/reports/GCDam/GC-Report-to-Congress2013-2014.pdf 2013-2014 Report to Congress ]
 
*[http://www.usbr.gov/uc/envdocs/reports/GCDam/GC-Report-to-Congress2010-2011.pdf 2010-2011 Report to Congress ]
 
*[http://www.usbr.gov/uc/envdocs/reports/GCDam/GC-Report-to-Congress2010-2011.pdf 2010-2011 Report to Congress ]
 
*[http://www.usbr.gov/uc/envdocs/reports/GCDam/GC-Report-to-Congress1999-2001.pdf 1999-2001 Report to Congress ]
 
*[http://www.usbr.gov/uc/envdocs/reports/GCDam/GC-Report-to-Congress1999-2001.pdf 1999-2001 Report to Congress ]
 
*[http://www.usbr.gov/uc/envdocs/reports/GCDam/GC-Report-to-Congress1998-1999.pdf 1998-1999 Report to Congress ]
 
*[http://www.usbr.gov/uc/envdocs/reports/GCDam/GC-Report-to-Congress1998-1999.pdf 1998-1999 Report to Congress ]
 +
 +
|-
 +
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b0bf; text-align:left; color:#000; padding:0.2em 0.4em;"> The Relationship Between Reclamation and Western Regarding Operating Glen Canyon </h2>
 +
|-
 +
|style="color:#000;"|
 +
 +
Reclamation’s Upper Colorado Region Water Office makes monthly water release schedules in acre-feet for Glen Canyon based upon anticipated inflows to the lake, release requirements to the lower basin and storage targets for the lake. This monthly water schedule is passed on to Western’s Resource Scheduling Office in Montrose, CO. Western’s scheduling office then develops an hourly release schedule. This schedule takes into account Glen Canyon ROD requirements and the requirements and agreements made by Western and Reclamation regarding the operation of the other CRSP powerplants. Western’s dispatch office in Phoenix, Arizona then provides Reclamation’s Glen Canyon Power Operations Center with a daily, 24 hour operating schedule, identifying Western’s desired hourly electric power schedule (in megawatts). This schedule is then put into the computer system at Glen Canyon by Reclamation (2). This schedule then becomes the megawatt quantities which are targeted during the “real time” operation at Glen Canyon Dam.
 +
 +
The Glen Canyon Power Operations Center operators utilize the generation schedule supplied by Western to operate the generating units while giving consideration to efficiency and equipment characteristics. In addition, the generators automatically respond to a “regulation signal” developed and electronically transmitted to the dam by Western for continuous response to power system load and frequency changes. (This is further described later in this paper). [https://www.wapa.gov/regions/CRSP/PlanProject/Pages/glen-canyon-operations.aspx]
 +
 +
|-
 +
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b0bf; text-align:left; color:#000; padding:0.2em 0.4em;"> Recent History of the "Flexibility" Within Operation Constraints </h2>
 +
|-
 +
|style="color:#000;"|
 +
 +
Shortly after Interim Flows began (August , 1991), Western met with staff at the Glen Canyon Environmental Studies (GCES) and with other Reclamation representatives. Western requested flexibility in order to regulate an electrical control area. This resulted in an agreement whereby Western was allowed to fluctuate 10% around any operational constraint and that Western would meet with GCES staff monthly to discuss any operational issues that surfaced. Thus, the Interim Flow downramp requirement of 1,500 cfs could be as high as 1,650 cfs and still be in compliance (1,500 cfs + 150 cfs).
 +
 +
After the ROD and Operating Criteria were signed, Western and Reclamation negotiated a MOU to more fully detail operational issues. Reclamation was interested in changing the 10% band width because it believed that the ROD and Operating Criteria didn’t specify that kind of flexibility. Instead, Western was allowed to use up to 1,000 cfs for regulation purposes. Compliance was to be monitored by SCADA using a one hour integrated value. It was thought that, even though a downramp at any one moment of time could be as high as 2,500 cfs (1,500 cfs + 1,000 cfs), it would be uncommon for the downramp to exceed 1,500 cfs since this is recorded as an integrated value over the hour. [https://www.wapa.gov/regions/CRSP/PlanProject/Pages/glen-canyon-operations.aspx]
 +
 +
|-
 +
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b0bf; text-align:left; color:#000; padding:0.2em 0.4em;"> Emergency Exception Criteria vs the Regulation of an Electrical Control Area </h2>
 +
|-
 +
|style="color:#000;"|
 +
 +
The EIS identified Emergency Exception Criteria as common elements in all alternatives. They are defined in the EIS as follows (3):
 +
 +
“Normal operations described under any alternative would be altered temporarily to respond to emergencies. NERC has established guidelines for the emergency operations of interconnected power systems. . . . Examples of system emergencies include:
 +
 +
*Insufficient generating capacity
 +
*Transmission system: overload, voltage control, and frequency
 +
*System restoration
 +
*Humanitarian situations (search and rescue)”
 +
 +
When emergency exception criteria are invoked, normal operations are suspended until the emergency has ended, or Western has discharged its North American Energy Reliability Council (NERC) responsibility regarding the emergency. Emergency exception criteria are further defined in the operating criteria and in the MOU on Glen Canyon operations signed by Western and Reclamation.
 +
 +
It was the invocation of emergency exception criteria on April 1st, 1998 which piqued the interest of some AMWG members in Reclamation and Western’s interpretation of the ROD.[https://www.wapa.gov/regions/CRSP/PlanProject/Pages/glen-canyon-operations.aspx]
 +
 +
|-
 +
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b0bf; text-align:left; color:#000; padding:0.2em 0.4em;"> Emergency Exception Criteria vs. Regulation </h2>
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|-
 +
|style="color:#000;"|
 +
 +
Both emergency exception criteria and regulation have been described in this paper. Recently, some members of the AMWG and TWG have focused their concerns and discussion on “emergencies”. However, the issue at hand and the subject of this paper is regulation. It is largely regulation that has resulted in the occasional exceedence of the 1,500 cfs downramp.[https://www.wapa.gov/regions/CRSP/PlanProject/Pages/glen-canyon-operations.aspx]
 +
 +
|-
 +
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b0bf; text-align:left; color:#000; padding:0.2em 0.4em;"> Policy Conclusions by Reclamation and Western </h2>
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|-
 +
|style="color:#000;"|
 +
 +
It does not seem reasonable that the ROD was intended to require either: 1) the exclusion of Glen Canyon Dam from participating in regulating a load control area, or 2) participation in regulating a load control area but limiting hourly load following to 500 cfs downramp (or something like it). Further, the environmental impact of regulation appears to be minimal, based on a review of the flows at the Lee Ferry gage. Finally, it has become clear to Reclamation and Western that precise and inviolate control of water releases from Glen Canyon Dam is beyond the capabilities of the machinery and electronic controls. For these reasons, Reclamation and Western intend to impose the following changes:
 +
 +
*Limit scheduled down ramps to 1,450 cfs (rather than 1,500),
 +
*Employ the use of SCADA table in the preparation of Western’s hourly schedules,
 +
*Investigate the transfer of a portion of the “ACE” to other CRSP powerplants,
 +
*Move the ACE signal back to Glen Canyon Dam (i.e. return “regulation” to the dam) once it has been demonstrated that the ACE will not cause “routine” excedences,
 +
*Work with the AMWG to determine the proper level of analysis required to address the potential downstream impacts of regulation in Glen and Grand Canyons,
 +
*Educate all interested parties on the power system and equipment operations and the associated results to water releases at the dam,
 +
*Add release data to Western’s web site and provide periodic reports to the TWG on the operation of Glen Canyon Dam and,
 +
*Continue efforts to for better coordination between Reclamation and Western regarding the scheduling and operation of Glen Canyon Dam.[https://www.wapa.gov/regions/CRSP/PlanProject/Pages/glen-canyon-operations.aspx]
 +
 +
 +
[[File:Glen_Canyon_Dam_filling.png|center|600px]] <br>
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The back of Glen Canyon Dam as Lake Powell was filling showing the 8 penstocks on the right and the two river outlet works on the left.
  
 
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|style="color:#000;"|
  
−
*[[Media:GCD Operating Criteria 1997.pdf| 1997 Operating Criteria for Glen Canyon Dam]]
+
*[https://www.usbr.gov/uc/DocLibrary/Memos/20240326-EstablishmentInterimOperatingGuidanceGlenCanyonDamLowReservoirLevels-TechnicalDecisionMemo-508-TSC.pdf Glen Canyon Dam Interim Low Elevation Operational Guidance]
 +
*[[Media:2017 Glen Canyon Operating Criteria Signed.pdf| 2017 Operating Criteria for Glen Canyon Dam]]
 +
*[http://ltempeis.anl.gov/documents/docs/LTEMP_ROD.pdf 2016 LTEMP Record of Decision (ROD)]
 +
*[http://ltempeis.anl.gov/documents/final-eis/ 2016 LTEMP EIS Final Draft (FEIS)]
 
*[https://www.usbr.gov/lc/region/programs/strategies.html 2007 Interim Guidelines for Lower Basin Shortages and Coordinated Operations for Lake Powell and Lake Mead]
 
*[https://www.usbr.gov/lc/region/programs/strategies.html 2007 Interim Guidelines for Lower Basin Shortages and Coordinated Operations for Lake Powell and Lake Mead]
 +
*[[Media:97-SLC-0333 BOR Glen Canyon Dam Operating Agmt.pdf| 1997 Operating Agreement between Reclamation and WAPA regarding the Operation of Glen Canyon Dam]]
 +
*[[Media:GCD Operating Criteria 1997.pdf| 1997 Operating Criteria for Glen Canyon Dam]]
 
*[https://www.wapa.gov/regions/CRSP/PlanProject/Pages/glen-canyon-operations.aspx Operations of Glen Canyon Dam under the 1996 ROD]
 
*[https://www.wapa.gov/regions/CRSP/PlanProject/Pages/glen-canyon-operations.aspx Operations of Glen Canyon Dam under the 1996 ROD]
 +
*[https://www.usbr.gov/uc/rm/amp/pdfs/sp_appndxG_ROD.pdf 1996 Record of Decision on the Operation of Glen Canyon Dam]
 +
*[https://www.usbr.gov/uc/envdocs/eis/gc/gcdOpsFEIS.html 1996 EIS on the Operation of Glen Canyon Dam]
 +
*[[Media:1980 GCD Transfer of Functions BOR WAPA.pdf| 1980 memo: Transfer of Functions and Property at Glen Canyon Dam from Reclamation to WAPA]]
 +
*[https://www.usbr.gov/uc/rm/crsp/index.html The Colorado River Basin Project ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2021-08-19-amwg-meeting/20210819-LawoftheRiverOverview-508-UCRO.pdf Law of the River Overview ]
  
 
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|style="color:#000;"|
 
|style="color:#000;"|
 +
 +
'''2024'''
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2024-05-15-amwg-meeting/20240515-BasinHydrologyOperations-508-UCRO.pdf Basin Hydrology and Operations ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2024-02-29-amwg-meeting/20240229-OperationPlanningUpdates-508-UCRO.pdf Operation Planning Updates ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2024-02-29-amwg-meeting/20240229-BasinHydrologyOperations-508-UCRO.pdf Basin Hydrology and Operations ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2024-01-25-twg-meeting/20240125-TWGMeeting-BasinHydrologyOperations-508-UCRO.pdf Basin Hydrology and Operations ]
 +
 +
'''2023'''
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2023-11-08-twg-meeting/20231108-BasinHydrologyOperationsWaterQuality-508-UCRO.pdf Basin Hydrology, Operations and Water Quality]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2023-08-17-amwg-meeting/20230817-BasinHydrologyOperations-508-UCRO.pdf Basin Hydrology and Operations]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2023-06-15-twg-meeting/20230615-BasinHydrologyOperationsWaterQuality-508-UCRO.pdf Basin Hydrology, Operations, and Water Quality]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2023-04-13-twg-meeting/20230413-BasinHydrologyOperations-508-UCRO.pdf Basin Hydrology and Operations]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2023-02-16-amwg-meeting/20230216-GlenCanyonDamOperationsUpperBasinHydrologyWaterQuality-508-UCRO.pdf Glen Canyon Dam Operations and Upper Basin Hydrology and Water Quality]
 +
 +
'''2022'''
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2022-10-13-twg-meeting/20221013-BasinHydrologyOperationsWaterQuality-508-UCRO.pdf Basin Hydrology, Operations and Water Quality ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2022-08-18-amwg-meeting/20220818-BasinHydrologyOperationsWaterQuality-508-UCRO.pdf Basin Hydrology, Operations and Water Quality ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2022-06-16-twg-meeting/20220616-BasinHydrologyOperationsWaterQuality-508-UCRO.pdf Basin Hydrology, Operations and Water Quality ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2022-05-18-amwg-meeting/20220518-BasinHydrologyOperations-508-UCRO.pdf Basin Hydrology and Operations ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2022-04-13-twg-meeting/20220413-BasinHydrologyOperationsWaterQuality-Presentation-508-UCRO.pdf Basin Hydrology, Operations, and Water Quality ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2022-02-10-amwg-meeting/20220210-BasinHydrologyWaterQualityOperations-508-UCRO.pdf Basin Hydrology, Water Quality, and Operations ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2022-01-13-twg-meeting/20220113-TWGMeeting-BasinHydrologyOperationsWaterQuality-508-UCRO.pdf Basin Hydrology, Operations and Water Quality ]
 +
 +
'''2021'''
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2021-06-17-twg-meeting/20210617-BasinHydrologyOperations-508-UCRO.pdf Basin Hydrology and Operations ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2021-05-19-amwg-meeting/20210519-BasinHydrologyOperation-Presentation-508-UCRO.pdf Basin Hydrology and Operations ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2021-04-14-twg-meeting/20210414-UpdateHydrologyOperationsWaterQualityConditions-508-UCRO.pdf Update on Hydrology, Operations and Water Quality Conditions ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2021-02-11-amwg-meeting/20210211-BasinHydrologyOperations-508-UCRO.pdf Basin Hydrology and Operations ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2021-01-22-twg-meeting/20210122-BasinHydrologyOperations-508-UCRO.pdf Basin Hydrology and Operations ]
 +
 +
'''2020'''
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2020-10-15-twg-meeting/20201015-OpsHydrologyTWG-508.pdf TWG Basin Hydrology and Operations ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2020-08-20-amwg-meeting/20200820-BasinHydrologyReservoirOperations2020-2021Hydrograph-Presentation-508-UCRO.pdf Basin Hydrology, Reservoir Operations 2020 and 2021 Hydrograph ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2020-08-20-amwg-meeting/20200820-7DReviewReportUpdate.pdf Review of the Colorado River Interim Guidelines for Lower Basin Shortages and Coordinated Operations for Lake Powell and Lake Mead ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2020-06-24-twg-meeting/20200624-HydrologyOperationsReservoirRelease-508-UCRO.pdf Hydrology, Operations and Reservoir Release presentation ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2020-05-20-amwg-meeting/20200520-AMWG-HydrologyOperationsReservoirRelease-508-UCRO.pdf Hydrology, Operations and Reservoir Release presentation ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2020-02-12-amwg-meeting/20200212-AMWG-HydrologyOperationsReservoirRelease-Presentation-508-UCRO.pdf Hydrology, Operations and Reservoir Release]
 +
 +
'''2019'''
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2019-10-21-twg-meeting/20191021-BasinHydrologyReservoirOperations2020Hydrograph-Presentation-508-UCRO.pdf Basin Hydrology, Reservoir Operations and 2020 Hydrograph Presentation ]
 +
 +
'''2018'''
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2018-10-10-twg-meeting/Attach_06.pdf Basin Hydrology, Water Years 2018-2019 Operations PPT]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2018-08-22-amwg-meeting/Attach_02.pdf Basin Hydrology, Reservoir Operations 2018 and 2019 Hydrograph]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2018-06-25-twg-meeting/Attach_04.pdf Basin Hydrology, Water Years 2018-2019 Operations PPT]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2018-05-22-amwg-meeting/Attach_02.pdf Basin Hydrology, Reservoir Operations 2018 and 2019 Hydrograph PPT]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2018-04-23-twg-meeting/Attach_06.pdf Basin Hydrology, Water Years 2018-2019 Operations PPT]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2018-02-14-amwg-meeting/Attach_03.pdf Basin Hydrology, Water Years 2018-2019 Operations PPT]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2018-01-25-twg-meeting/AR21.pdf Basin Hydrology, Operations and 2018 Hydrograph PPT]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2018-01-25-twg-meeting/Attach_04.pdf Basin Hydrology, Water Years 2018-2019 Operations PPT]
 +
*[http://www.yumaheritage.com/docs/2nd-A-1JackSchmidt_USU_LoganUT.pdf?bcsi_scan_16614fa24ff8c4a5=0&bcsi_scan_filename=2nd-A-1JackSchmidt_USU_LoganUT.pdf Urban Waterfronts 2018]
  
 
'''2017'''
 
'''2017'''
−
*[[Media:Feb2017 OperationsCall.pdf| February 2017 Glen Canyon Montly Operational Coordination Call]]
+
*[https://www.usbr.gov/uc/progact/amp/twg/2017-04-20-twg-meeting/Attach_03.pdf Basin Hydrology and Operations]
−
*[https://www.usbr.gov/uc/rm/amp/amwg/mtgs/17feb15/Fill%20Mead%20First.pdf Analysis of Water Losses and Impacts to the Grand Canyon Ecosystem of the "Fill Mead First" Proposal and PPT]
+
*[[Media:Feb2017 OperationsCall.pdf| February 2017 Glen Canyon Monthly Operational Coordination Call]]
−
*[https://www.usbr.gov/uc/rm/amp/amwg/mtgs/17feb15/Hydrology.pdf Basin Hydrology, and 2017-2018 Operations]
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2017-02-15-amwg-meeting/Attach_16.pdf Analysis of Water Losses and Impacts to the Grand Canyon Ecosystem of the "Fill Mead First" Proposal]
−
*[https://www.usbr.gov/uc/rm/amp/twg/mtgs/17jan26/A4_Davidson.pdf Basin Hydrology, Operations and 2018 Hydrograph]
+
*[https://qcnr.usu.edu/wats/colorado_river_studies/files/documents/Fill_Mead_First_Exec_Summary.pdf Fill Mead First: A technical assessment (Summary)]
 +
*[https://qcnr.usu.edu/wats/colorado_river_studies/files/documents/Fill_Mead_First_Analysis.pdf Fill Mead First: A technical assessment (Analysis)]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2017-02-15-amwg-meeting/Attach_05.pdf Basin Hydrology, and 2017-2018 Operations]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2017-01-26-twg-meeting/A6_Davidson.pdf Basin Hydrology, Operations and 2018 Hydrograph]
  
 
'''2016'''
 
'''2016'''
−
*[https://qcnr.usu.edu/wats/colorado_river_studies/files/documents/Fill_Mead_First_Exec_Summary.pdf FILL MEAD FIRST: A technical assessment (Summary)]
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2016-08-24-amwg-meeting/Attach_05.pdf Basin Hydrology and Water Year (WY) 2017 Hydrograph]
−
*[https://qcnr.usu.edu/wats/colorado_river_studies/files/documents/Fill_Mead_First_Analysis.pdf FILL MEAD FIRST: A technical assessment (Analysis)]
+
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/16aug24/Attach_05.pdf Basin Hydrology and Water Year (WY) 2017 Hydrograph]
+
 
*[[Media:Aug2016 Information.pdf| August 2016 DOI-DOE Federal Family call on Glen Canyon Operations ]]
 
*[[Media:Aug2016 Information.pdf| August 2016 DOI-DOE Federal Family call on Glen Canyon Operations ]]
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/16may25/Attach_02.pdf Basin Hydrology, Operations, and 2017 Hydrograph]
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2016-05-25-amwg-meeting/Attach_02.pdf Basin Hydrology, Operations, and 2017 Hydrograph]
 
*[[Media:2017 Hydrology PPT.pdf | TWG: Basin Hydrology, Operations, and 2017 Hydrograph]]
 
*[[Media:2017 Hydrology PPT.pdf | TWG: Basin Hydrology, Operations, and 2017 Hydrograph]]
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/16feb24/pdf/Attach_08.pdf AMWG: Basin Hydrology, Operations, and 2017 Hydrograph]
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2016-02-24-amwg-meeting/Attach_08.pdf Basin Hydrology, Operations, and 2017 Hydrograph]
−
*[http://www.usbr.gov/uc/rm/amp/twg/mtgs/16jan26/documents/Attach_03.pdf Glen Canyon Dam operations during equalization]
+
*[https://www.usbr.gov/uc/progact/amp/twg/2016-02-26-twg-meeting/Attach_03.pdf Glen Canyon Dam operations during equalization]
  
 
'''2015'''
 
'''2015'''
 
*[https://drive.google.com/file/d/0BwY-Z2c3NTUGMHhacTF4enJ1eGs/view 2016 Annual Operating Plan]
 
*[https://drive.google.com/file/d/0BwY-Z2c3NTUGMHhacTF4enJ1eGs/view 2016 Annual Operating Plan]
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/15may28/Attach_05.pdf AMWG: Basin Hydrology and WY 2016 Hydrograph]
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2015-05-28-amwg-meeting/Attach_05.pdf Basin Hydrology and WY 2016 Hydrograph]
−
*[http://www.usbr.gov/uc/rm/amp/twg/mtgs/15apr21/Attach_03.pdf TWG: Hydrology Update and 2016 Hydrograph]
+
*[https://www.usbr.gov/uc/progact/amp/twg/2015-04-21-twg-meeting/Attach_03.pdf Hydrology Update and 2016 Hydrograph]
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/15feb25/Attach_03a.pdf Panel on Current Projects and Issues in Utah]
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2015-02-25-amwg-meeting/Attach_03a.pdf Panel on Current Projects and Issues in Utah]
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/15feb25/Attach_03b.pdf Central Utah Project]
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2015-02-25-amwg-meeting/Attach_03b.pdf Central Utah Project]
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/15feb25/Attach_03c.pdf Meeting the Mitigation Requirement for the Bonneville Unit CUP]
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2015-02-25-amwg-meeting/Attach_03c.pdf Meeting the Mitigation Requirement for the Bonneville Unit CUP]
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/15feb25/Attach_03d.pdf Current Projects and Issues in Utah]
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2015-02-25-amwg-meeting/Attach_03d.pdf Current Projects and Issues in Utah]
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/15feb25/Attach_03e.pdf Provo Area Office]
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2015-02-25-amwg-meeting/Attach_03e.pdf Provo Area Office]
  
 
'''2014'''
 
'''2014'''
−
*[http://www.usbr.gov/uc/rm/amp/twg/mtgs/14oct28/Attach_09.pdf Colorado River Annual Operating Plan and Drought Contingency Planning ]
+
*[https://www.usbr.gov/uc/progact/amp/twg/2014-10-28-twg-meeting/Attach_09.pdf Colorado River Annual Operating Plan and Drought Contingency Planning ]
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/14aug27/Attach_02a.pdf Basin Hydrology, Operations ]
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2014-08-27-amwg-meeting/Attach_02a.pdf Basin Hydrology, Operations ]
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/14aug27/Attach_02b.pdf DOI-DOE Hydrograph Development for Water Year 2015  ]
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2014-08-27-amwg-meeting/Attach_02b.pdf DOI-DOE Hydrograph Development for Water Year 2015  ]
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/14may27/Attach_01.pdf Basin Hydrology, Operations, and 2015 Hydrograph and Development of Water Year 2015 Hydrograph ]  
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2014-05-27-amwg-meeting/Attach_01.pdf Basin Hydrology, Operations, and 2015 Hydrograph and Development of Water Year 2015 Hydrograph ]  
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/14feb19/Attach_02.pdf Basin Hydrology, Operations, and 2015 Hydrograph ]  
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2014-02-19-amwg-meeting/Attach_02.pdf Basin Hydrology, Operations, and 2015 Hydrograph ]  
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/14feb19/Attach_03a.pdf Panel on the Potential Effects of Long-Term Drought on Colorado River Operations ]  
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2014-02-19-amwg-meeting/Attach_03a.pdf Panel on the Potential Effects of Long-Term Drought on Colorado River Operations ]  
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/14feb19/Attach_03b.pdf Near Term Risks: Options to Address Declining Reservoirs ]  
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2014-02-19-amwg-meeting/Attach_03b.pdf Near Term Risks: Options to Address Declining Reservoirs ]  
−
*[http://www.usbr.gov/uc/rm/amp/amwg/mtgs/14feb19/Attach_03c.pdf State of Nevada Concerns ]  
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2014-02-19-amwg-meeting/Attach_03c.pdf State of Nevada Concerns ]  
  
 
'''2013'''
 
'''2013'''
−
*[https://www.usbr.gov/uc/rm/amp/twg/mtgs/13jun26/Attach_04.pdf Colorado River Basin Hydrology and Projected Glen Canyon Dam Operations ]
+
*[https://www.usbr.gov/uc/progact/amp/amwg/2013-08-08-amwg-meeting/Attach_04.pdf Water Year 2014 Hydrograph ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2013-08-08-amwg-meeting/Attach_03.pdf Basin Hydrology and Operations ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2013-06-26-twg-meeting/Attach_04.pdf Colorado River Basin Hydrology and Projected Glen Canyon Dam Operations ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2013-02-20-amwg-meeting/Attach_02.pdf Basin Hydrology and Operations]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2013-02-20-amwg-meeting/Attach_04.pdf Glen Canyon Dam Facility Management]
 +
 
 +
'''2012'''
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2012-08-29-amwg-meeting/Attach_06a.pdf Water Year 2013 Hydrograph ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2012-08-29-amwg-meeting/Attach_06b.pdf TWG Report: 2013 Hydrograph ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2012-06-20-twg-meeting/Attach_04a.pdf DOI and DOE Operating Hydrograph Recommendations for GCD (2012 water year)]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2012-06-20-twg-meeting/Attach_04b.pdf Water Year 2013 Hydrograph TWG Motion ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2012-02-22-amwg-meeting/Attach_05.pdf 2013 Hydrograph Development ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2012-02-22-amwg-meeting/Attach_09.pdf Basin Hydrology and Operations ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2012-02-02-twg-meeting/Attach_07.pdf FY2013 Hydrograph (from 8/2011 AMWG meeting)]
 +
 
 +
'''2011'''
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2011-08-24-amwg-meeting/Attach_09.pdf 2012 Hydrograph ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2011-06-28-twg-meeting/Attach_06a.pdf 2012 Hydrograph Development ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2011-06-28-twg-meeting/Attach_06b.pdf Department of the Interior and Department of Energy Operating Hydrograph Recommendations for Glen Canyon Dam (2012 Water Year), June 6, 2011]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2011-05-18-amwg-meeting/Attach_04.pdf WY2012 Hydrograph Development ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2011-03-08-twg-meeting/Attach_05a.pdf 2012 Hydrograph Development ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2011-03-08-twg-meeting/Attach_05b.pdf Grand Canyon Trust Proposed FY2012 Hydrograph]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2011-01-20-twg-meeting/Attach_04a.pdf Bureau of Reclamation Updates ]
 +
 
 +
'''2010'''
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2010-08-24-amwg-meeting/Attach_06.pdf Basin Hydrology and Operations]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2010-08-24-amwg-meeting/Attach_07a.pdf Fiscal Year 2011-12 Hydrograph and E-mail Message to the AMWG from Anne Castle Dated July 23, 2010, Subject: July 23 Final Draft DOI-DOE Proposed Hydrograph Recommendations]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2010-08-24-amwg-meeting/Attach_07b.pdf Department of the Interior and Department of the Energy Recommendations for Glen Canyon Dam with August 23, 2010, edits]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2010-08-24-amwg-meeting/Attach_07c.pdf Grand Canyon Protection Act]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2010-08-24-amwg-meeting/Attach_07d.pdf Report on Modeling the 2008-2010 Period to Support Development of the 2011 Hydrograph]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2010-08-24-amwg-meeting/Attach_07e.pdf Proposed Water year 2011 Hydrograph: Impacts on CRSP Electric Power Resources]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2010-08-24-amwg-meeting/Attach_07f.pdf Grand Canyon Trust Hydrograph Proposal]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2010-01-21-twg-meeting/Attach_03b.pdf Figure 1, AOP, BOR, AMWG monthly volumes]
 +
 
 +
'''2009'''
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2009-08-12-amwg-meeting/Attach_08a.pdf FY2010-11 Draft Budget, Worplan, and Hydrograph]
 +
 
 +
'''2006'''
 +
*[https://pubs.usgs.gov/of/2006/1243/pdf/of06-1243_508.pdf Hazel et al. 2006. Stage-Discharge Relations for the Colorado River in Glen, Marble, and Grand Canyons, Arizona: U.S. Geological Survey Open-File Report 2006-1243, 7 p]
 +
 
 +
'''2004'''
 +
*[http://www.riversimulator.org/Resources/AquaticResearch/MLFFfailureKorman2004.pdf ***DRAFT*** Evidence for the Failure of the Modified Low Fluctuating Flow Alternative (MLFFA) to Benefit Most Ecological Resources in Grand Canyon ]
 +
 
 +
'''2003'''
 +
*[https://pubs.usgs.gov/pp/pp1677/pdf/pp1677.pdf Topping et al. 2003.  Computation and analysis of the instantaneous-discharge record for the Colorado River at Lees Ferry, Arizona, May 8, 1921 through September 30, 2000: U.S. Geological Survey Professional Paper 1677, 118 p.]
  
 
|-
 
|-
−
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b0bf; text-align:left; color:#000; padding:0.2em 0.4em;"> Operational Flexibility </h2>  
+
! <h2 style="margin:0; background:#cedff2; font-size:120%; font-weight:bold; border:1px solid #a3b0bf; text-align:left; color:#000; padding:0.2em 0.4em;"> Operations under MLFF [http://ltempeis.anl.gov/documents/final-eis/vol1/Chapter_2-Alternatives.pdf] </h2>
 
|-
 
|-
 
|style="color:#000;"|
 
|style="color:#000;"|
  
−
In addition to daily scheduled fluctuations for power generation, the instantaneous releases from Glen Canyon Dam may also fluctuate to provide 40 megawatts (mw) of system regulation. These instantaneous release adjustments stabilize the electrical generation and transmission system and translate to a range of about 1,200 cfs above or below the hourly scheduled release rate.  Under system normal conditions, fluctuations for regulation are typically short lived and generally balance out over the hour with minimal or no noticeable impacts on downstream river flow conditions.
+
[[File:MLFF volumes.jpg|left|400px]]
 +
[[File:MLFF hydrograph.jpg|left|400px]]
 +
 
 +
'''Minimum flows:'''
 +
*8,000 cfs between 7 a.m. and 7 p.m.
 +
*5,000 cfs between 7 p.m. and 7 a.m.
 +
 
 +
'''Maximum non-experimental flows:'''
 +
*25,000 cfs
 +
 
 +
'''Daily range:'''
 +
*5,000 for monthly volumes <600 kaf
 +
*6,000 for monthly volumes 600– 800 kaf
 +
*8,000 for monthly volumes >800 kaf
  
−
Releases from Glen Canyon Dam can also fluctuate beyond scheduled releases when called upon to respond to unscheduled power outages or power system emergencies.  Depending on the severity of the system emergency, the response from Glen Canyon Dam can be significant, within  the full range of the operating capacity of the power plant for as long as is necessary to maintain balance in the transmission system.  Glen Canyon Dam typically maintains 30 mw (approximately 880 cfs) of generation capacity in reserve in order to respond to a system emergency even when generation rates are already high.  System emergencies occur fairly infrequently and typically require small responses from Glen Canyon Dam.  However, these responses can have a noticeable impact on the river downstream of Glen Canyon Dam. [https://www.usbr.gov/uc/water/crsp/cs/gcd.html]
+
'''Ramp rates:'''
 +
*4,000 cfs/hr up
 +
*1,500 cfs/hr down
  
 
|-
 
|-
Line 137: Line 363:
 
|-
 
|-
 
|style="color:#000;"|
 
|style="color:#000;"|
 +
 +
==How much water can be released at Glen Canyon Dam?==
 +
* 8 generators = 4,000 cfs each = 32,000 cfs <br> (note that there is usually one or two generators down for maintenance at any given time)
 +
* 4 bypass tubes = 3,750 cfs each = 15,000 cfs
 +
* 2 spillways = up to 208,000 cfs [http://www.usbr.gov/lc/region/g4000/AOP2014/AOP14_2nd_Consultation_PPT.pdf]
 +
 +
==Critical water elevations==
 +
*3715' = dam crest elevation
 +
*3700' = top of spillway gates (3704' with plywood flashboards)
 +
*3648' = spillway crest elevation
 +
*3490' = minimum power pool (to prevent cavitation in the penstocks)
 +
*3470' = penstock elevation (this is the centerline elevation, the penstocks are 15' in diameter)
 +
*3374' = bypass tube elevation (this is the centerline elevation, the bypass tubes are 8' in diameter)
 +
*3370' = reservoir deadpool elevation [http://www.riversimulator.org/Resources/USBR/GCDtechnicalData.pdf]
 +
 +
==How fast do water and waves flow down the Grand Canyon?==
 +
*[https://pubs.usgs.gov/fs/FS-168-97/pdf/fs-168-97.pdf The Colorado River in Grand Canyon: How Fast Does It Flow?]
 +
Discharge waves move downstream faster than the water. For example, in May 1991, the discharge waves produced by rapidly changing dam releases moved through the canyon in about 1 2/3 days, whereas the water took about 4 1/3 days to travel the 235 miles from Lees Ferry to Gneiss Canyon.
 +
 +
*[https://rrfw.org/RaftingGrandCanyon/Tide_Tables?fbclid=IwAR3EArfvBzN5J6oVGVb353fPC-C4Ngo174-7yvcFDssm2PL9Y9qfMp5HiC8 Tide Tables]
  
 
== Video of the construction of Glen Canyon Dam ==
 
== Video of the construction of Glen Canyon Dam ==
Line 146: Line 392:
 
*[https://www.youtube.com/watch?v=Cpo1UMflJtk Challenge at Glen Canyon (Part 3)]
 
*[https://www.youtube.com/watch?v=Cpo1UMflJtk Challenge at Glen Canyon (Part 3)]
  
−
== What is the total release (CFS) possible from Glen Canyon Dam? ==
+
 
−
*Total release during a HFE = Power plant capacity + 15,000 cfs through the bypass tubes
+
−
*Capacity depends on how many of the 8 units are available. [http://www.usbr.gov/lc/region/g4000/AOP2014/AOP14_2nd_Consultation_PPT.pdf]
+
 
|-
 
|-
  

Latest revision as of 17:04, 20 November 2024

LTEMPmonthlyvolumes.jpg

Operations of Glen Canyon Dam

The LTEMP Record of Decision (ROD) on the operation of Glen Canyon Dam was signed on December 15, 2016. It changed operations at Glen Canyon from the 1996 ROD that implemented the MLFF flow regime.

Minimum flows:
LTEMP monthly volumes.png
  • 8,000 cfs between 7 a.m. and 7 p.m.
  • 5,000 cfs between 7 p.m. and 7 a.m.

Maximum non-experimental flows:

  • 25,000 cfs

Daily range:

  • June–August: Equal to 10 × monthly volume (in kaf)
  • All other months: 9 × monthly volume (in kaf)
  • Daily range not to exceed 8,000 cfs

Ramp rates:

  • 4,000 cfs/hr up
  • 2,500 cfs/hr down


Current Status
Current Operations Inflow Forecasts
and Model Projections

Updates

Glen Canyon Monthly Operational Call

The DOI also will conduct monthly Glen Canyon Dam operational coordination meetings or calls with the DOI bureaus (USGS, NPS, FWS, BIA, and Reclamation), WAPA, AZGFD, and representatives from the Basin States and the UCRC. Each DOI bureau will provide updates on the status of resources and dam operations. In addition, WAPA will provide updates on the status of the Basin Fund, projected purchase power prices, and its financial and operational considerations. These meetings or calls are intended to provide an opportunity for participants to share and obtain the most up-to-date information on dam operational considerations and the status of resources (including ecological, cultural, Tribal, recreation, and the Basin Fund). One liaison from each Basin State and from the UCRC will be allowed to participate in the monthly operational coordination meetings or calls. [1]

Archived Glen Canyon Monthly Operations Call slides

Critical Reservoir Elevations at Powell and Mead

Glen Canyon critical elevations.png


Mead critical elevations.png

USBR Monthly/Annual Reports

Report to Congress Regarding Operations of Glen Canyon Dam[2]

The Relationship Between Reclamation and Western Regarding Operating Glen Canyon

Reclamation’s Upper Colorado Region Water Office makes monthly water release schedules in acre-feet for Glen Canyon based upon anticipated inflows to the lake, release requirements to the lower basin and storage targets for the lake. This monthly water schedule is passed on to Western’s Resource Scheduling Office in Montrose, CO. Western’s scheduling office then develops an hourly release schedule. This schedule takes into account Glen Canyon ROD requirements and the requirements and agreements made by Western and Reclamation regarding the operation of the other CRSP powerplants. Western’s dispatch office in Phoenix, Arizona then provides Reclamation’s Glen Canyon Power Operations Center with a daily, 24 hour operating schedule, identifying Western’s desired hourly electric power schedule (in megawatts). This schedule is then put into the computer system at Glen Canyon by Reclamation (2). This schedule then becomes the megawatt quantities which are targeted during the “real time” operation at Glen Canyon Dam.

The Glen Canyon Power Operations Center operators utilize the generation schedule supplied by Western to operate the generating units while giving consideration to efficiency and equipment characteristics. In addition, the generators automatically respond to a “regulation signal” developed and electronically transmitted to the dam by Western for continuous response to power system load and frequency changes. (This is further described later in this paper). [3]

Recent History of the "Flexibility" Within Operation Constraints

Shortly after Interim Flows began (August , 1991), Western met with staff at the Glen Canyon Environmental Studies (GCES) and with other Reclamation representatives. Western requested flexibility in order to regulate an electrical control area. This resulted in an agreement whereby Western was allowed to fluctuate 10% around any operational constraint and that Western would meet with GCES staff monthly to discuss any operational issues that surfaced. Thus, the Interim Flow downramp requirement of 1,500 cfs could be as high as 1,650 cfs and still be in compliance (1,500 cfs + 150 cfs).

After the ROD and Operating Criteria were signed, Western and Reclamation negotiated a MOU to more fully detail operational issues. Reclamation was interested in changing the 10% band width because it believed that the ROD and Operating Criteria didn’t specify that kind of flexibility. Instead, Western was allowed to use up to 1,000 cfs for regulation purposes. Compliance was to be monitored by SCADA using a one hour integrated value. It was thought that, even though a downramp at any one moment of time could be as high as 2,500 cfs (1,500 cfs + 1,000 cfs), it would be uncommon for the downramp to exceed 1,500 cfs since this is recorded as an integrated value over the hour. [4]

Emergency Exception Criteria vs the Regulation of an Electrical Control Area

The EIS identified Emergency Exception Criteria as common elements in all alternatives. They are defined in the EIS as follows (3):

“Normal operations described under any alternative would be altered temporarily to respond to emergencies. NERC has established guidelines for the emergency operations of interconnected power systems. . . . Examples of system emergencies include:

  • Insufficient generating capacity
  • Transmission system: overload, voltage control, and frequency
  • System restoration
  • Humanitarian situations (search and rescue)”

When emergency exception criteria are invoked, normal operations are suspended until the emergency has ended, or Western has discharged its North American Energy Reliability Council (NERC) responsibility regarding the emergency. Emergency exception criteria are further defined in the operating criteria and in the MOU on Glen Canyon operations signed by Western and Reclamation.

It was the invocation of emergency exception criteria on April 1st, 1998 which piqued the interest of some AMWG members in Reclamation and Western’s interpretation of the ROD.[5]

Emergency Exception Criteria vs. Regulation

Both emergency exception criteria and regulation have been described in this paper. Recently, some members of the AMWG and TWG have focused their concerns and discussion on “emergencies”. However, the issue at hand and the subject of this paper is regulation. It is largely regulation that has resulted in the occasional exceedence of the 1,500 cfs downramp.[6]

Policy Conclusions by Reclamation and Western

It does not seem reasonable that the ROD was intended to require either: 1) the exclusion of Glen Canyon Dam from participating in regulating a load control area, or 2) participation in regulating a load control area but limiting hourly load following to 500 cfs downramp (or something like it). Further, the environmental impact of regulation appears to be minimal, based on a review of the flows at the Lee Ferry gage. Finally, it has become clear to Reclamation and Western that precise and inviolate control of water releases from Glen Canyon Dam is beyond the capabilities of the machinery and electronic controls. For these reasons, Reclamation and Western intend to impose the following changes:

  • Limit scheduled down ramps to 1,450 cfs (rather than 1,500),
  • Employ the use of SCADA table in the preparation of Western’s hourly schedules,
  • Investigate the transfer of a portion of the “ACE” to other CRSP powerplants,
  • Move the ACE signal back to Glen Canyon Dam (i.e. return “regulation” to the dam) once it has been demonstrated that the ACE will not cause “routine” excedences,
  • Work with the AMWG to determine the proper level of analysis required to address the potential downstream impacts of regulation in Glen and Grand Canyons,
  • Educate all interested parties on the power system and equipment operations and the associated results to water releases at the dam,
  • Add release data to Western’s web site and provide periodic reports to the TWG on the operation of Glen Canyon Dam and,
  • Continue efforts to for better coordination between Reclamation and Western regarding the scheduling and operation of Glen Canyon Dam.[7]


Glen Canyon Dam filling.png

The back of Glen Canyon Dam as Lake Powell was filling showing the 8 penstocks on the right and the two river outlet works on the left.


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Operations under MLFF [8]

MLFF volumes.jpg
MLFF hydrograph.jpg

Minimum flows:

  • 8,000 cfs between 7 a.m. and 7 p.m.
  • 5,000 cfs between 7 p.m. and 7 a.m.

Maximum non-experimental flows:

  • 25,000 cfs

Daily range:

  • 5,000 for monthly volumes <600 kaf
  • 6,000 for monthly volumes 600– 800 kaf
  • 8,000 for monthly volumes >800 kaf

Ramp rates:

  • 4,000 cfs/hr up
  • 1,500 cfs/hr down

Other Stuff

How much water can be released at Glen Canyon Dam?

  • 8 generators = 4,000 cfs each = 32,000 cfs
    (note that there is usually one or two generators down for maintenance at any given time)
  • 4 bypass tubes = 3,750 cfs each = 15,000 cfs
  • 2 spillways = up to 208,000 cfs [9]

Critical water elevations

  • 3715' = dam crest elevation
  • 3700' = top of spillway gates (3704' with plywood flashboards)
  • 3648' = spillway crest elevation
  • 3490' = minimum power pool (to prevent cavitation in the penstocks)
  • 3470' = penstock elevation (this is the centerline elevation, the penstocks are 15' in diameter)
  • 3374' = bypass tube elevation (this is the centerline elevation, the bypass tubes are 8' in diameter)
  • 3370' = reservoir deadpool elevation [10]

How fast do water and waves flow down the Grand Canyon?

Discharge waves move downstream faster than the water. For example, in May 1991, the discharge waves produced by rapidly changing dam releases moved through the canyon in about 1 2/3 days, whereas the water took about 4 1/3 days to travel the 235 miles from Lees Ferry to Gneiss Canyon.

Video of the construction of Glen Canyon Dam

1983 flood videos and spillway repairs
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