Difference between revisions of "WATER QUALITY"

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The combination of the record five-year drought (1999-2004) and above average runoff into Lake Powell during the spring and summer of 2005 put large amounts of sediment and organic matter from the reservoir's delta into the lake. These substances consumed oxygen as they decay which, in turn, resulted in declining dissolved oxygen concentrations in the Colorado River immediately below the dam. While this phenomenon occurs to some degree every summer and fall, oxygen levels in 2005 reached a level that caused concern for the health of the trout fishery in the river below the dam.  
+
[[File:ForebayTemp 2000 2016.jpg|thumb|center|400px|Forebay temperature 2000-2016 [https://www.usbr.gov/uc/progact/amp/twg/2017-01-26-twg-meeting/AR4_Radtke.pdf https://www.usbr.gov/uc/progact/amp/twg/2017-01-26-twg-meeting/AR4_Radtke.pdf] ]]
 +
[[File:ForebayDO 2000 2016.jpg|thumb|center|400px|Forebay dissolved oxygen 2000-2016 [https://www.usbr.gov/uc/progact/amp/twg/2017-01-26-twg-meeting/AR4_Radtke.pdf https://www.usbr.gov/uc/progact/amp/twg/2017-01-26-twg-meeting/AR4_Radtke.pdf] ]]
  
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As the river moves downstream, the water cascades through rapids, quickly raising the dissolved oxygen levels, so there is less impact or concern for endangered native fish in the reaches of the Grand Canyon. However, there may be some impact to the non-native trout fishery as fish remaining near the dam become lethargic or temporarily move downstream to more oxygen-rich waters.
+
===WQ field parameters measured monthly at forebay and quarterly throughout reservoir===
 +
*Depth
 +
*Temperature
 +
*Dissolved Oxygen
 +
*pH
 +
*Conductivity / TDS
 +
*ORP
 +
*Turbidity
 +
*Chl a
 +
*Secchi Depth
 +
*Meteorological Information
  
−
Reclamation conducted short-term experiments to evaluate the relationship between dam operations and dissolved oxygen concentrations. Researchers from the Grand Canyon Monitoring and Research Center determined if low releases spread among varying numbers of generating units will inject more oxygen into the water. The turbines draw some air during operation, especially when operated at very low output levels. Various operational combinations of three to five units were tested.
+
===WQ samples sent for lab analysis===
−
 
+
*Major ions
−
While some changes in dissolved oxygen were been noted as a result of the experiments, a concern also has emerged. Operating the units at very low levels is both inefficient and damaging. Because the generating units were designed to operate efficiently only at higher releases, normal operations for low flows would be met by using fewer units. If the units are operated at too low a level, the risk of damage to the turbines increases significantly. While units have been operated that low in the past for various system and emergency reasons, every effort possible has been made to minimize the length of such operations to protect the generating units. Additionally, such "rough operation" also is inefficient in both the generation of power and the use of water.
+
*pH
−
 
+
*Conductivity
−
The results of these studies indicate the turbines can contribute to improved dissolved oxygen concentrations in the water being released from the reservoir. The studies remain inconclusive concerning the best balance of turbine operations, or whether other alternatives should be developed.
+
*TDS, roe & soc
−
 
+
*TSS
−
The issue of declining dissolved oxygen becomes less of an issue by October or early November when the water in Lake Powell "turns over." This happens when the cooling air temperatures and seasonal winds mix reservoir waters, essentially causing the upper, better oxygenated water to mix with the lower level water that contains low oxygen. [http://www.usbr.gov/newsroom/newsrelease/detail.cfm?RecordID=8041]
+
*Alkalinity
 +
*DOC
 +
*OP
 +
*TP
 +
*NH3-N
 +
*NO3+NO2-N
 +
*TN
 +
*Chl
 +
*Phytoplankton / Zooplankton
 +
*Metals (once per year, UT)
  
 
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! <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;">Links and Information </h2>
 +
|-
 +
|style="color:#000;"|
 +
 +
*[http://gcdamp.com/index.php?title=Portal:GCDAMP_Knowlege_Assessments GCMRC Annual Reports page]
 +
*[http://gcdamp.com/index.php?title=Nutrients Nutrients Page]
 +
*[http://gcdamp.com/index.php?title=TEMPERATURE Temperature Page]
 +
 +
|-
 +
! <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;"> Water Quality PEP Reviews </h2>
 +
|-
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|style="color:#000;"|
 +
 +
*[http://gcdamp.com/index.php?title=2017_Water_Quality_PEP 2017 Water Quality PEP]
 +
*[[Media:Jones 2001 Final report PEP GCMRC IWQP.pdf| Final report of the 2001 Protocol Evaluation Panel for the Grand Canyon Monitoring and Research Center Integrated Water Quality Program (IWQP)]]
 +
 +
|-
 
! <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;">Water Quality Gages</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;">Water Quality Gages</h2>
 
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 +
*[https://tableau.usgs.gov/views/colorado-river-water-quality-gcd/GlenCanyonDamSiteHourlyAverages?%3Aembed=y&%3AisGuestRedirectFromVizportal=y Glen Canyon Dam Site: Hourly Averages]
 +
*[https://www.gcmrc.gov/discharge_qw_sediment/station/GCDAMP/09379901 Glen Canyon Dam near Page, AZ]
 
*[http://www.gcmrc.gov/discharge_qw_sediment/station/GCDAMP/09380000 Colorado River at Lees Ferry]
 
*[http://www.gcmrc.gov/discharge_qw_sediment/station/GCDAMP/09380000 Colorado River at Lees Ferry]
−
*[http://www.gcmrc.gov/discharge_qw_sediment/station/GCDAMP/09383050 Colorado River at 30 mile]
+
*[http://www.gcmrc.gov/discharge_qw_sediment/station/GCDAMP/09383050 Colorado River near river mile 30]
−
*[http://www.gcmrc.gov/discharge_qw_sediment/station/GCDAMP/09383100 Colorado River above LCR]
+
*[http://www.gcmrc.gov/discharge_qw_sediment/station/GCDAMP/09383100 Colorado River above Little Colorado River near Desert View, AZ]
−
*[http://www.gcmrc.gov/discharge_qw_sediment/station/GCDAMP/09403000 Bright Angel Creek]
+
*[https://www.gcmrc.gov/discharge_qw_sediment/station/GCDAMP/09402500 Colorado River near Grand Canyon, AZ]
−
*[http://www.gcmrc.gov/discharge_qw_sediment/station/GCDAMP/09404120 Colorado River abv National Canyon]
+
*[http://www.gcmrc.gov/discharge_qw_sediment/station/GCDAMP/09404120 Colorado River above National Canyon near Supai, AZ]
−
*[http://www.gcmrc.gov/discharge_qw_sediment/station/GCDAMP/09404200 Colorado River bl Diamond Creek]
+
*[http://www.gcmrc.gov/discharge_qw_sediment/station/GCDAMP/09404200 Colorado River above Diamond Creek near Peach Springs, AZ]
  
 
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 +
'''2023'''
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2023-11-08-twg-meeting/20231108-WaterQualityConditionsLakePowell-508-UCRO.pdf Water Quality Conditions in Lake Powell and below Glen Canyon Dam]
 +
*[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/twg/2023-11-08-twg-meeting/20231108-GlenCanyonDamAirInjectionTestingSeptember2023-508-UCRO.pdf Glen Canyon Dam Air Injection Testing September 2023]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2023-08-17-amwg-meeting/20230817-EffectsLowDissolvedOxygenHighTemperatureTroutFishery-508-UCRO.pdf Effects of Low Dissolved Oxygen and High Temperature on the Trout Fishery]
 +
*[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/2023-01-26-twg-meeting/20230126-AnnualReportingMeeting-PredictingWaterQualityLakePowell-508-UCRO.pdf Predicting Water Quality in Lake Powell: Updates and Improvements to the Existing Mechanistic Model ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2023-01-26-twg-meeting/20230126-AnnualReportingMeeting-DissolvedOxygenDynamicsLakePowellGlenCanyonTailwater-508-UCRO.pdf Dissolved Oxygen Dynamics in Lake Powell and in the Glen Canyon Tailwater]
 +
 +
'''2022'''
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2022-10-13-twg-meeting/20221013-WaterQualitySynthesisUpdate-508-UCRO.pdf Water Quality Synthesis Update ]
 +
*[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/twg/2022-10-13-twg-meeting/20221013-LowDissolvedOxygenReleasesCurrentState-of-Practice-TechnicalReport-UCRO.pdf Low Dissolved Oxygen in Releases: Current State-of-Practice - Technical Report No. ENV-2022-61 ]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2022-08-18-amwg-meeting/20220818-DissolvedOxygenState-of-PracticeStudy-508-UCRO.pdf Dissolved Oxygen State-of-Practice Study ]
 +
*[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/2022-02-10-amwg-meeting/20220210-BasinHydrologyWaterQualityOperations-508-UCRO.pdf Basin Hydrology, Water Quality, 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/twg/2022-04-13-twg-meeting/20220413-LakePowellWaterQualityMarch2021-March2022-508-UCRO.pdf Lake Powell Water Quality March 2021-March 2022 ]
 +
 +
'''2021'''
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2021-10-14-twg-meeting/20211014-UpdateGlenCanyonDamLakePowellDissolvedOxygenState-of-PracticeProject-Presentation-508-UCRO.pdf Update on the Glen Canyon Dam/Lake Powell Dissolved Oxygen State-of-Practice Project]
 +
 +
'''2020'''
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2020-06-24-twg-meeting/20200624-MetalimnionLowDissolvedOxygenEventsLakePowell-508-UCRO.pdf Metalimnion low dissolved oxygen events in Lake Powell and their transport downstream of Glen Canyon Dam ]
 +
*[https://doi.org/10.1002/lno.11399 Deemer et al., 2020, Calcite precipitation in Lake Powell reduces alkalinity and total salt loading to the Lower Colorado River Basin: Limnology and Oceanography  ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2020-01-13-twg-meeting/20200113-AnnualReportingMeeting-DissolvedOxygenDownstreamGlenCanyonDam2019-Presentation-508-UCRO.pdf Dissolved Oxygen Downstream of Glen Canyon Dam, 2019 ]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2020-01-13-twg-meeting/20200113-AnnualReportingMeeting-LakePowellRegulatorDownstreamWaterQualityEcosystemProductivity-Presentation-508-UCRO.pdf Lake Powell as a Regulator of Downstream Water Quality and Ecosystem Productivity ]
 +
 +
'''2018'''
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2018-10-10-twg-meeting/Attach_05.pdf Lake Powell Water Quality Program PPT]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2018-08-22-amwg-meeting/Attach_12.pdf GCMRC Science Updates PPT]
 +
*[http://www.bioone.org/doi/10.1674/0003-0031-180.1.119 Stone et al., 2018, Abiotic Controls of Invasive Nonnative Fishes in the Little Colorado River, Arizona. The American Midland Naturalist]
  
 
'''2017'''
 
'''2017'''
 +
*[http://dx.doi.org/10.1002/lom3.10204 Payn et al., 2017, A coupled metabolic-hydraulic model and calibration scheme for estimating of whole-river metabolism during dynamic flow conditions: Limnology and Oceanography: Methods, v.15, no.10, p. 847-866]
 
*[http://dx.doi.org/10.1002/lno.10726  Bernhardt et al. 2017. The metabolic regimes of flowing waters: Limnology and Oceanography]
 
*[http://dx.doi.org/10.1002/lno.10726  Bernhardt et al. 2017. The metabolic regimes of flowing waters: Limnology and Oceanography]
−
*[https://www.usbr.gov/uc/rm/amp/twg/mtgs/17jan26/AR4_Radtke.pdf Water Quality in Lake Powell and Its Influence on the Colorado River Below Glen Canyon Dam PPT]
+
*[https://www.usbr.gov/uc/progact/amp/twg/2017-01-26-twg-meeting/AR4_Radtke.pdf Water Quality in Lake Powell and Its Influence on the Colorado River Below Glen Canyon Dam PPT]
  
 
'''2016'''
 
'''2016'''
 
*[http://pubs.usgs.gov/fs/2016/3053/fs20163053.pdf Voichick et al. 2016. Water clarity of the Colorado River—Implications for food webs and fish communities: U.S. Geological Survey Fact Sheet 2016–3053, 4 p.]
 
*[http://pubs.usgs.gov/fs/2016/3053/fs20163053.pdf Voichick et al. 2016. Water clarity of the Colorado River—Implications for food webs and fish communities: U.S. Geological Survey Fact Sheet 2016–3053, 4 p.]
−
*[https://www.usbr.gov/uc/rm/amp/twg/mtgs/16jan26/documents/AR01_Topping.pdf Project 2: Streamflow,  Water Quality, Sediment Transport, and Sand Budgets in the Colorado River Ecosystem]
+
*[https://www.usbr.gov/uc/progact/amp/twg/2016-02-26-twg-meeting/AR01_Topping.pdf Project 2: Streamflow,  Water Quality, Sediment Transport, and Sand Budgets in the Colorado River Ecosystem]
  
 
'''2015'''
 
'''2015'''
 
*[https://pubs.usgs.gov/ds/471/pdf/ds471.pdf Historical Physical and Chemical Data for Water in Lake Powell and from Glen Canyon Dam Releases, Utah-Arizona, 1964–2013]
 
*[https://pubs.usgs.gov/ds/471/pdf/ds471.pdf Historical Physical and Chemical Data for Water in Lake Powell and from Glen Canyon Dam Releases, Utah-Arizona, 1964–2013]
−
*[http://www.usbr.gov/uc/rm/amp/twg/mtgs/15apr21/Attach_07.pdf Water Quality in Lake Mead and Upstream Influences: Dissolved Oxygen during 2014]
+
*[https://www.usbr.gov/uc/progact/amp/twg/2015-04-21-twg-meeting/Attach_07.pdf Water Quality in Lake Mead and Upstream Influences: Dissolved Oxygen during 2014]
−
*[http://www.usbr.gov/uc/rm/amp/twg/mtgs/15jan20/Attach_01.pdf Streamflow, Water Quality, and Sediment Transport in the Colorado River Ecosystem]
+
*[https://www.usbr.gov/uc/progact/amp/twg/2015-01-20-twg-meeting/Attach_01.pdf Streamflow, Water Quality, and Sediment Transport in the Colorado River Ecosystem]
−
*[http://www.usbr.gov/uc/rm/amp/twg/mtgs/15jan20/Attach_16.pdf Glen Canyon Physical Environment Update – Water Quality, Tributary Influences & Channel Analyses & Flows]
+
*[https://www.usbr.gov/uc/progact/amp/twg/2015-01-20-twg-meeting/Attach_16.pdf Glen Canyon Physical Environment Update – Water Quality, Tributary Influences & Channel Analyses & Flows]
  
 
'''2014'''
 
'''2014'''
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'''2010'''
 
'''2010'''
 
*[http://crc.nv.gov/files.php/news/462536e751a496f28b512c3a16167f88/CRC-News-2010-04-24 Effects of Drought on Water Quality of Lake Powell and Glen Canyon Dam Releases]
 
*[http://crc.nv.gov/files.php/news/462536e751a496f28b512c3a16167f88/CRC-News-2010-04-24 Effects of Drought on Water Quality of Lake Powell and Glen Canyon Dam Releases]
−
*[https://www.usbr.gov/uc/rm/amp/twg/mtgs/10nov15/Attach_11d.pdf Update on Water Quality and 2010 Sand Input ]
+
*[https://www.usbr.gov/uc/progact/amp/twg/2010-11-15-twg-meeting/Attach_11d.pdf Update on Water Quality and 2010 Sand Input ]
 +
 
 +
'''2009'''
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2009-04-29-amwg-meeting/Attach_03a.pdf Grand Canyon Monitoring and Research Center (GCMRC) Update]
 +
*[https://www.usbr.gov/uc/progact/amp/amwg/2009-04-29-amwg-meeting/Attach_03d.pdf Water Quality and Sediment, 2008 High Flow Experiment, and Integrated Flow, Temperature, and Sediment Modeling PPT]
 +
*[https://www.usbr.gov/uc/progact/amp/twg/2009-03-16-twg-meeting/Attach_11.pdf Final Report of the Protocol Evaluation Panel for the GCMRC Integrated Water Quality Program]
  
 
'''2006'''
 
'''2006'''
−
*[https://www.usbr.gov/uc/rm/amp/twg/mtgs/06nov08/Attach_06.pdf Update on Water Quality of Lake Powell and Glen Canyon Dam Releases]
+
*[https://www.usbr.gov/uc/progact/amp/twg/2006-11-08-twg-meeting/Attach_06.pdf Update on Water Quality of Lake Powell and Glen Canyon Dam Releases]
  
 
'''2005'''
 
'''2005'''
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==Adding power generation to the bypass tubes==
 
==Adding power generation to the bypass tubes==
−
Allows for drawing water from deeper in Lake Powell: colder and more oxygenated water
+
Allows for drawing water from deeper in Lake Powell where colder and more oxygenated water may be present.
 
*[[Media:Generation at Outlet Glen Canyon Dam Plan of Study CRSP Power Peaking Capacity (March 1981).pdf|Generation at Outlet Glen Canyon Dam Plan of Study CRSP Power Peaking Capacity (March 1981)]]
 
*[[Media:Generation at Outlet Glen Canyon Dam Plan of Study CRSP Power Peaking Capacity (March 1981).pdf|Generation at Outlet Glen Canyon Dam Plan of Study CRSP Power Peaking Capacity (March 1981)]]
 +
 +
==Other methods:==
 +
*Forebay diffusers
 +
*Side stream super-saturation
 +
*Aeration
 +
*Turbine venting
 +
*Surface water pumps (impellers)
 +
[http://www.mobleyengineering.com/technologies/hydropowerenhancements.html (Mobley Engineering: Hydropower Enhancement Technologies)]
  
 
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Latest revision as of 16:39, 18 January 2024
ForebayWaterQuality.jpg

Desired Future Condition for Water Quality

Water quality with regards to dissolved oxygen, nutrient concentrations and cycling, turbidity, temperature, etc., is sufficient to support natural ecosystem functions, visitor safety and visitor experience to the extent feasible and consistent with the life history requirements of focal aquatic species.
• Ecosystem-sustaining nutrient distribution, flux, and cycling.
• Hydro-physical conditions and characteristics of the CRE necessary to sustain aquatic biota.
• Acceptable water quality for human health and visitor experience.

---
 ---
---

Updates

Forebay temperature 2000-2016 https://www.usbr.gov/uc/progact/amp/twg/2017-01-26-twg-meeting/AR4_Radtke.pdf
Forebay dissolved oxygen 2000-2016 https://www.usbr.gov/uc/progact/amp/twg/2017-01-26-twg-meeting/AR4_Radtke.pdf

WQ field parameters measured monthly at forebay and quarterly throughout reservoir

  • Depth
  • Temperature
  • Dissolved Oxygen
  • pH
  • Conductivity / TDS
  • ORP
  • Turbidity
  • Chl a
  • Secchi Depth
  • Meteorological Information

WQ samples sent for lab analysis

  • Major ions
  • pH
  • Conductivity
  • TDS, roe & soc
  • TSS
  • Alkalinity
  • DOC
  • OP
  • TP
  • NH3-N
  • NO3+NO2-N
  • TN
  • Chl
  • Phytoplankton / Zooplankton
  • Metals (once per year, UT)


Links and Information

Water Quality PEP Reviews

Water Quality Gages

Papers and presentations

2023

2022

2021

2020

2018

2017

2016

2015

2014

2012

2010

2009

2006

2005

Modifying releases at Glen Canyon Dam to improve water quality in the Lees Ferry reach

Rough operation of the turbines

Increases the oxygenation of water going through the power plant Is damaging to the turbines

Oxygenation of the tailwater using the bypass tubes

The Basin States have maintained that according to Sec 602a of the Colorado River Basin Project Act (1968), the bypass tubes at Glen Canyon Dam can only be used to avoid anticipated spills from Lake Powell. The Basin States have agreed to bypass at Glen Canyon Dam for HFEs on the condition that it be done as part of an experiment and not a management action or operational decision. Costs associated with any release that bypasses the powerplant for reasons other than to avoid a spill or for experimentation relating to HFEs would have to be borne by the GCDAMP (see DOI determination for costs of the 2004 BHBF).

Adding power generation to the bypass tubes

Allows for drawing water from deeper in Lake Powell where colder and more oxygenated water may be present.

Other methods:

  • Forebay diffusers
  • Side stream super-saturation
  • Aeration
  • Turbine venting
  • Surface water pumps (impellers)

(Mobley Engineering: Hydropower Enhancement Technologies)

Other Stuff
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