WSP12637

• File Number: 8282.300
• Description: Colorado River Operations and Accounting - Lower Basin Administrative Procedures
• State: CO
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 8/1/1996
• Author: DOI-BOR
• Title: Description and Assessment of Operations-Maintenance and Sensitive Species of the Lower Colorado River - Volume I - Report - 08-01-96
• Water Supply Pro - Doc Type: Report/Study

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feet ............................................... 16

Figure 5. Side-view schematic of lower Colorado River from Pierce Ferry to the SIB . 17
Figure 6. Natural flow at Lees Ferry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 39
Figure 7. Flow below Hoover Dam . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 40
Figure 8. Lake Meadend-of-month elevations - 1935 to 1996 . . . . . . . . . . . . . . .. 41
Figure 9. Typical season flow of Colorado River below Davis Dam ............ 43
Figure 10. Typical spring flows on Colorado River below Parker Dam .......... 44
Figure 11. Typical summer flows on Colorado River below Parker Dam ......... 45
Figure 12. Typical fall flows on Colorado River below Parker Dam ........ . . .. 46
Figure 13. Typical winter flows on Colorado River below Parker Dam .......".. 47
Figure 14. Copy of Release Schedule (a) and Actual Release (b) from Parker Dam . .. 51
Figure 15. . Lake Havasu operational constraints. . . . . . . . . . . . . . . . . . . . . . . .. 53
Figure 16. Typical dynamic power ,generation measured at the Hoover Dam 230-kV bus

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . It .. 54

Figure 17. Lake Moh~ve pre-1998 (curve A) and post-1998 (curve B) operational constraints

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 55

Figure 18. Hoover actual releases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 57
Figure 19. Davis actual releases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 58
Figure 20. Parker actual releases for October 28, 1994 . . . . . . . . . . . . . . . . . . .. 59
Figure 21. Three-Finger Lake Project ............................... 65
Figure 22. Boulder City Wetland. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 67
Figure 23. Lower Imperial Division Wetland Enhancement. . . . . . . . . . . . . . . . .. 69
Figure 24. 1879-1977' Comparison of vegetation communities along same stretch of lower
Colorado River near Blythe, California. . . . . . . . . . . . . . . . . . . . . . . . .. 84
Figure 25. Historic lower Colorado River floodplain and associated vegetation communities

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 85

Figure 26. Reconstruction of native plant community placement and species composition
from original surveyor notes and plats along the lower Colorado River in 1879 . 86
Figure 27. Examples of vertical configurations for the vegetation structural types .... 89
Figure 28. 1995 Colorado River delta at Lake Mead vegetation classification. . . . . .. 92
Figure 29. Areas of known occurrence of desert tortoises in Arizona . . . . . . . . . . . . 136
Figure C-1. Quarry Sites. Map No. 423-LC-222 ............... Appendix C - 4
Figure D1. List of owner/operators for major facilities along the lower Colorado River

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Appendix D - 8

Figure E-l. Map and operational diagram of the lower Colorado River [Map Number 423-
300-59 (Revised April 1993)] . . . . . . . . . . . . . . . . . . . . . . . . Appendix E - 10
Figure El. Hoover daily release . . . . . . . . . . . . . . . . . . . . . . . . . . Appendix E - 11
Figure E2. Hoover daily flow duration . . . . . . . . . . . . . . . . . . . . . . Appendix E - 12
Figure E3. Hoover daily mean release range .................. Appendix E - 13
Figure E4. Hoover actual releases. . . . . . . . . . . . . . . . . . . . . . . . . Appendix E - 14
Figure ES. Lake Mead daily elevation ...................... Appendix E - 15
Figure E6. Lake Mead daily elevation range .................. Appendix E - 16
Figure E7. Lake Mead monthly elevation change . . . . . . . . . . . . . . . . Appendix E - 17
Figure E8. Davis daily release . . . . . . . . . . . . . . . . . . . . . . . . . . . Appendix E - 18

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