WSP10725

• File Number: 8240.200.43.A.2
• Description: Grand Valley/Orchard Mesa
• State: CO
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 3/1/2003
• Title: Endangered Fish Passage Project at the Grand Valley Project Diversion Dam and Fish Screen in the Highline Canal - Final Environmental Assessment
• Water Supply Pro - Doc Type: Publication

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, Final GVP Fish Passage EA

Table of Contents

CHAPTER I-iNTRODUCTION ......................................................................................1
Need for and Purpose of Action....................................................,...................:......3

Background Information ....... ..................................................... ..........,........ ...........3
Scoping ........... .......... .......... ...'. ......... ...........,..,.......:. ...............................................4

CHAPTER 2 - ALTERNATIVES ......................................................................................7

Fish Passage Alternatives ... ......................................................................... ............ 7
Design Criteria............................................................................................. 7
Rock Fish Passage Alternative... .... ....,.,....'................. ......,............. .............8
Concrete Fish Passage Alternative,............................................................ 10
Fish Screen Alternatives ........................................................................................10
Fish Passage Preferred Alternative ........................................................................14
Fish Screen Preferred Alternative..........................................................................15

Construction........................................................................................................ ...16
Operation, Maintenance and Replacement Measures.................................,..........18
Water Supply for Fish Passage and Fish Screening...............................................l8
Alternatives Eliminated From Analysis..............................,......................,......,.... 19

Environmental Commitments ...... .......... .... ........ ." ,.'...'........, ... ....,..........,........ ......20

CHAPTER 3 - AFFECTED ENVIRONMENT AND ENVIRONMENTAL

CONSEQUENCES ...........................................,................................................................21
General.......... ..................... ........,...........................................................................21
Water Resources ................................ ............. ........... ....... ........ ................. ....... .....22
Water Rights and Use ................................................................................22

Water Quality ................................................. ........................,...................23
Recreation Resources ................................ ...,............................ ...................... ".....24
River Boating and Public Safety ................................................................24

Land and Facility Resources ............ ...................................................... ................25
Protect Existing Structures....................,................................,.................. .25

Access ............ ................... ............................................ .................. ...........27
Unique Geographical Features.... .......................... ..........,. .....................................28

Prime and Unique FannIand ......................................................................29
Floodplain and Wetlands Protection..........................................................29
Fish and Wildlife Resources ..........................................................................,.......31
Effects on Colorado River Fishes ..............................................................32

Cultural Resources......................................................................... ..................... ...34
Protect Historic Dam and Canal................................................................35

Indian Trust Assets .,...............................,.............................................................. 3 6
Environmental Justice........................................................................................... .36
Social and Economic Factors .... ............ ........... ...... ..... .......................,...... ....,........36
Hydropower .... ..... ..... ,.............. .... ............ ......................... ................. .... ....36
Cost and Benefits.......................................................................................3 8
Summary and Mitigation Measures.......................................................................39

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