WSPC12525 ‎(2)‎

• File Number: 8220.101.10
• Description: Colorado River Water Projects - Glen Canyon Dam-Lake Powell - Adaptive Management
• State: CO
• Basin: Colorado Mainstem
• Date: 6/2/1998
• Author: DOI-GCMRC
• Title: Assessment of Impacts of Glen Canyon Dam Operations on Water Quality Resources in Lake Powell and the Colorado River in Grand Canyon - Grand Canyon Monitoring and Research Center - Draft - 06-02-98
• Water Supply Pro - Doc Type: Report/Study

002375

List of Figures

Fig. 1: [Top] Thermal stratification and longitudinal zones of Lake Powell with structural
attributes of Glen Canyon Dam.
[Bottom] Conductivity plot with Lake Powell?s circulation cells present for past
and present seasons.
Fig. 2a: Monthly longitudinal plots of one typical year?S progression from stratification
of summer through seasonal changes back to summer. Some irregularities may
exist in the data, particularly in the dissolved oxygen. Penstocks and river outlet
levels indicated.
Fig. 2b: [Top] Sequence of 6 conductivity longitudinal isopleths that demonstrate the
most common annual scenario of winter bottom flows.
[Bottom] Example of 3 possible winter underflow currents: Underflow, overflow
and equi-potential flow-through for conductivity, dissolved oxygen, and
temperature.
Fig. 3a: Temperature, conductivity, and dissolved oxygen at the forebay of Lake Powell
from December 1964 to July 1997. Spillways, penstocks, and jet tubes indicated.
Sample sites annotated with dots. Qualitative hydrograph for outflow in blue,
inflow in red, spillways and jet tubes at their elevation.
Fig. 3b: Temperature, conductivity, dissolved oxygen at Wahweap (forebay) station in
Lake Powell from February 1992 to August 13, 1997, including results from
experimental flood (red line). Penstocks indicated at 1057.7 m & jet tubes at
1028.4 m elevation. Hydrograph of inflow is indicated by red line and outflow in
blue.
Fig. 4: Conductivity, temperature, and dissolved oxygen for 1965 and 1966. Before
during and after Lake Mead. Depth of penstocks (1057.7 m) and jet tubes
(1028.4 m) indicated by black lines.
Fig. 5: Longitudinal profiles of Lake Powell for February, March, April and May, 1973.
Drawdown of Lake Powell in anticipation of large spring flood and concerns of
inundation of Rainbow Bridge National Monument. Penstock discharges were
elevated from March 22, 1973 to May 1, 1973. Discharges during elevated
releases averaged 27 K cfs, accounting for 2.29 MAF
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