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Fish Passage
Barrier and Surface Water
Diversion Screening Assessment and Prioritization Manual
December 2009 - Manual
Updated
The
purpose of the Fish Passage Barrier and Surface Water Diversion
Screening Assessment and Prioritization Manual is to provide
guidance on how to locate, assess, and prioritize fish passage problems
(culverts, dams, and fishways) and surface water diversion screening problems.
For additional information
contact:
WDFW Habitat Program
360-902-2534
tapps@dfw.wa.gov
INTRODUCTION
This manual was originally written in 1998 to provide a standardized methodology for evaluating fish passage at road crossings. The manual has since been expanded to include evaluation of additional instream features, including dams, fishways, other human-made instream structures, natural barriers, and surface water diversions. Revisions to the prior version of this manual (August 2000) are summarized in the table below.
This manual is intended to provide guidance for conducting fish passage and surface water diversion inventories. Fish passage inventories lead to identification and assessment of instream features and prioritization of fish passage barriers based on amount, quality, and species utilization of habitat upstream of the barrier. Surface water diversion inventories allow for the identification, assessment, and prioritization of unscreened or inadequately screened diversions in need of correction.
|
Location |
Title |
Details of the update |
|
Chapter 3 |
Road Crossing Structures – Culverts |
Added table for guidance in estimating the percent passability for barrier culverts. Also includes photo examples of different road crossings. |
|
Chapter 3 |
Non-culvert Road Crossings |
New section. |
|
Chapter 3 |
Level A flow chart |
Updated flow chart of the Level A culvert analysis. |
|
Chapter 3 |
Photo Examples |
New figures, including photo examples of different road crossing structures, and tide and flood gates. |
|
Chapter 4 |
Dams |
Expanded discussion on dams, including feature description and evaluating fish passage. Added data collection attributes table. Included photo examples of different dam structures. |
|
Chapter 5 |
Miscellaneous Obstructions |
New section on ‘Other’ human-made fish passage features (that are not classified as culverts or dams). Includes photo examples of miscellaneous obstructions. |
|
Chapter 6 |
Natural Barriers |
New section. |
|
Chapter 7 |
Fishways |
Added section on evaluating fishways associated with culverts, dams, and other features. Included data collection attributes table. |
|
Chapter 7 |
Photo Examples of Fishways |
New figure. |
|
Chapter 8 |
Surface Water Diversion/Screen Evaluation |
Updated text, figures, and data collection table. Includes photo examples of common screens. |
|
Chapter 9 |
Habitat Assessment |
Eliminated the Expanded Threshold Determination (ETD) option for estimating habitat gain. This method had a very low confidence level due to several factors. A map-based assessment does not identify additional upstream and downstream human-made barriers, or natural barriers that may prematurely end a habitat survey. The actual length of fish bearing waters is difficult to accurately assess using the map-based method, leading to the possibility of overestimation or underestimation of actual habitat. |
|
Chapter 9 |
Physical Habitat Survey |
Discontinued using the term Ordinary High Water (OHW). Now using the term Scour Line Width (SLW), referring to one of the channel width measurements taken for making fish passage and habitat assessments. Refer to Glossary in Appendix A for definitions of terms. |
|
Appendix A |
Glossary of Terms |
New. |
|
Appendix B |
Recommended Equipment List |
New. |
|
Appendix D |
Measuring Channel Width (Appendix ‘H’ from the Design of Road Culverts for Fish Passage) |
Added. |
|
Appendix E |
Basic Culvert Surveying Techniques |
New. |
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