WSP12636

• 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 II - Appendices-Etc - 08-01-96
• Water Supply Pro - Doc Type: Report/Study

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2. Endangered Razorback Sucker and Bony tail Conservation . . . . . . .. 61
a. Native Fish Work Group ....................... 61
b. Willow Beach National Fish Hatchery ............... 62
c. HA VFISH Project ........................... 63
d. Boulder City Golf Course Native Fish Rearing Project ..... 63
e. Hualapai Native Fish Rearing Facility . . . . . . . . . . . . . . .. 63
3. Native Riparian Plant Restoration. . . . . . . . . . . . . . . . . . . . . .. 63
a. Native Riparian Plant Nurseries ................... 64
b. Demonstration Projects ........................ 64
c. Enhancement Projects ......................... 64

d. Research ................................. 64

4. Three-Finger Lake Project . . . . . . . . . . . . . . . . . . . . . . . . . .. 64
5. Boulder City Wetland Project . . . . . . . . . . . . . . . . . . . . . . . .. 66
6. Lower Imperial Division Wetland Enhancement . . . . . . . . . . . . .. 68
7. Las Vegas Wash Wetland Restoration .................... 71
8. Multi-Species Conservation Program Development ............ 71
E. Summary of Secretary's Non-Discretionary and Discretionary Operation and
Maintenance of the Lower Colorado River ................... 72

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 72

2. Non-discretionary ................................ 72
3. Varying Degrees of Discretion ........................ 72
3. Fully Discretionary ............................... 74

ID. ENVIRONMENTAL BASELINE. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. 76
A. Historic and Present Biological Communities on the Lower Colorado River . 76

1. Introduction . . . . . . . . . . . . '. . . . . . . . . . . . . . . . . . . . . . .. 76

2. Riparian Communities ............................. 83

a. Historic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 83

b. Present .................................. 87

3. Marsh ....................................... 91

a. Historic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 91

b. Present .................................. 94

4. Aquatic ...................................... 96

a. Historic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 96

b. Development Along the Lower Colorado River. . . . . . . . . . 100
c. Effects of Development and Present Day Aquatic Baseline ... 106
B. Previous and Ongoing Section 7 Consultations . . . . . . . . . . . . . . . . . . . 111
1. Colorado River Mainstem ........................... 111
2. Baseline Projects . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . 111
a. Central Arizona Project Havasu Diversion . . . . . . . . . . . . . 111
b. Southern Nevada Water System (Robert B. Griffith Water Project)

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

3. Salton Sea and Endangered Desert Pupfish . . . . . . . . . . . . . . . . . 116
C. Non-Federal (Contemporaneous and Cumulative) Actions ............ 116

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