Key Peninsula, Gig Harbor, and Islands Watershed Nearshore Salmon Habitat Assessment
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Key Peninsula, Gig Harbor, and Islands Watershed Nearshore Salmon Habitat Assessment Final Report Prepared for Pierce County Public Works and Utilities, Environmental Services, Water Programs July 3, 2003 12570-01 Anchorage Key Peninsula, Gig Harbor, and Islands Watershed Nearshore Salmon Habitat Assessment Boston Final Report Prepared for Denver Pierce County Public Works and Utilities, Environmental Services, Water Programs 9850 - 64th Street West University Place, WA 98467 Edmonds July 3, 2003 12570-01 Eureka Prepared by Pentec Environmental Jersey City Jon Houghton Cory Ruedebusch Senior Biologist Staff Biologist Long Beach J. Eric Hagen Andrea MacLennan Project Biologist Environmental Scientist Portland Juliet Fabbri Environmental Scientist A Division of Hart Crowser, Inc. Seattle 120 Third Avenue South, Suite 110 Edmonds, Washington 98020-8411 Fax 425.778.9417 Tel 425.775.4682 CONTENTS Page SUMMARY v ACKNOWLEDGEMENTS vi INTRODUCTION 1 Background 1 Key Peninsula-Gig Harbor-Islands Watershed 1 Objectives 2 General Approach 3 NEARSHORE HABITAT ASSESSMENT METHODS 4 Information Sources 4 ShoreZone Inventory 4 Shoreline Photos 5 Drift Cell/Sector Data 5 Priority Habitats and Species 5 2002 Habitat Surveys 5 Tidal Habitat Model 5 Littoral Shoreline Surveys 7 Macrovegetation Surveys 7 GIS Database Development 8 Additional Data Presentations 9 RESULTS 10 General 10 Shoreline Types 10 EMU Descriptions 12 EMU 1 12 EMU 2 13 EMU 3 14 EMU 4 14 EMU 5 15 EMU 6 16 EMU 7 17 EMU 8 18 EMU 9 18 EMU 10 19 EMU 11 21 Pentec Environmental Page i 12570-01 July 3, 2003 CONTENTS (Continued) Page EMU 12 22 EMU 13 24 EMU 14 25 EMU 15 26 Restoration Opportunities 27 EMU 1 27 EMU 2 28 EMU 3 28 EMU 4 29 EMU 5 29 EMU 6 29 EMU 7 30 EMU 8 30 EMU 9 31 EMU 10 31 EMU 11 32 EMU 12 32 EMU 13 33 EMU 14 34 EMU 15 34 DISCUSSION 34 REFERENCES 37 TABLES 1 Restoration Opportunities in the KGI Study Area 2 KGI Watershed Nearshore Salmonid Habitat Assessment Tidal Habitat Model Question Answer Frequency FIGURES 1 EMU Boundaries 2 EMU 01 Relative Habitat Quality 3 EMU 01 Feeder Bluffs and Bulkheads 4 EMU 01 Eelgrass Observations 5 EMU 02 Relative Habitat Quality 6 EMU 02 Feeder Bluffs and Bulkheads 7 EMU 02 Eelgrass Observations Pentec Environmental Page ii 12570-01 July 3, 2003 CONTENTS (Continued) 8 EMU 03 Relative Habitat Quality 9 EMU 03 Feeder Bluffs and Bulkheads 10 EMU 03 Eelgrass Observations 11 EMU 04 Relative Habitat Quality 12 EMU 04 Feeder Bluffs and Bulkheads 13 EMU 04 Eelgrass Observations 14 EMU 05 Relative Habitat Quality 15 EMU 05 Feeder Bluffs and Bulkheads 16 EMU 05 Eelgrass Observations 17 EMU 06 Relative Habitat Quality 18 EMU 06 Eelgrass Observations 19 EMU 06 Feeder Bluffs and Bulkheads 20 EMU 07 Relative Habitat Quality 21 EMU 07 Eelgrass Observations 22 EMU 07 Feeder Bluffs and Bulkheads 23 EMU 08 Relative Habitat Quality 24 EMU 08 Feeder Bluffs and Bulkheads 25 EMU 08 Eelgrass Observations 26 EMU 09 Relative Habitat Quality 27 EMU 09 Feeder Bluffs and Bulkheads 28 EMU 09 Eelgrass Observations 29 EMU 10 Relative Habitat Quality 30 EMU 10 Feeder Bluffs and Bulkheads 31 EMU 10 Eelgrass Observations 32 EMU 11-South Relative Habitat Quality 33 EMU 11-North Relative Habitat Quality 34 EMU 11-South Feeder Bluffs and Bulkheads 35 EMU 11-North Feeder Bluffs and Bulkheads 36 EMU 12 Relative Habitat Quality 37 EMU 12 Feeder Bluffs and Bulkheads 38 EMU 12 Eelgrass Observations 39 EMU 13 Relative Habitat Quality 40 EMU 13 Eelgrass Observations 41 EMU 13 Feeder Bluffs and Bulkheads 42 EMU 14 Relative Habitat Quality 43 EMU 14 Feeder Bluffs and Bulkheads 44 EMU 14 Eelgrass Observations 45 EMU 15 Relative Habitat Quality 46 EMU 15 Feeder Bluffs and Bulkheads 47 EMU 15 Eelgrass Observations Pentec Environmental Page iii 12570-01 July 3, 2003 CONTENTS (Continued) APPENDIX A PHOTOGRAPHS APPENDIX B MANUAL FOR USE AND APPLICATION OF SEWIP TIDAL HABITAT MODEL APPENDIX C TIDAL HABITAT MODEL SCORE SHEET APPENDIX D GIS DATABASE USERS GUIDE Pentec Environmental Page iv 12570-01 July 3, 2003 SUMMARY This report presents results of a nearshore salmon habitat assessment for the approximately 179 miles of marine shoreline in western Pierce County, Washington. The study area includes the shorelines of the Key Peninsula; the Gig Harbor Peninsula; and Fox, McNeil, and Anderson islands, as well as several smaller islands. Collectively, this area is referred to as the Key Peninsula–Gig Harbor–Islands (KGI) Watershed. Although it is located within the study area, McNeil Island is owned by the state and therefore will not be included in any of Pierce County’s preservation or restoration plans. Because of its limited shoreline development, however, McNeil Island was included in the field assessment as a reference site. The KGI Watershed encompasses the southeastern portion of East Kitsap Watershed, Water Resource Inventory Area (WRIA) 15. Phase 1 of this work included gathering and evaluating existing background data that are relevant to the KGI shorelines; data have been drawn from a variety of sources. Upon review of these data, as well as available tools for conducting the shoreline inventory, the Technical Advisory Group concluded that the Tidal Habitat Model (THM) was an appropriate framework for assessing shoreline conditions and associated habitat quality and function for juvenile salmonids. The THM, which previously has been used by the study team to inventory shorelines in WRIA 7 and 8, can also be used to evaluate and prioritize restoration opportunities. In Phase 2, we conducted a field reconnaissance of the entire shoreline of the KGI study area to gather data with which to complete the shoreline inventory and the THM application. In areas where the field observations of eelgrass presence did not match the eelgrass maps in the Washington State Department of Natural Resources (DNR) ShoreZone database, we completed additional surveys using an underwater video camera system to confirm eelgrass distribution. Field data were used to score each shoreline assessment area using the THM and were imported into a Geographic Information System (GIS) for mapping of important indicators of habitat quality and/or stressors. The 179 miles of shoreline in the study area were divided into 15 large subareas (ecological management units, EMU) of similar geographic and hydrographic characteristics. These subareas were further divided into 413 smaller reaches of shoreline (assessment units, AU) with relatively homogeneous littoral and riparian characteristics, and were scored with the THM. AUs within each EMU were ranked relative to the highest scoring AUs in the EMU to provide a ready measure of the best and poorest salmon habitat within each EMU. Typically the higher scoring AUs had features such as feeder bluffs, large eelgrass beds, or Pentec Environmental Page v 12570-01 July 3, 2003 sources of large woody debris (LWD) that provide ecological benefit to areas beyond the boundaries of the AUs. Lower scoring AUs were those that have been altered by human activities such as bulkheading, overwater structures, and riparian degradation. The relative condition of salmon habitat among EMUs was also determined by comparison of the mean of THM scores. Highest ranking EMUs were those with the least shoreline modification, for example, around McNeal Island and along the west side of the Tacoma Narrows; Gig Harbor, which has extensive shoreline modification and overwater structures, had the lowest mean EMU score. During the course of the assessment, AUs that have been disturbed by human activity, but which retain a high potential for habitat restoration, were identified. Potential restoration actions most prevalent throughout the study area include bulkhead and fill removal, riparian enhancement, removal of derelict structures, and restoration of connectivity between the nearshore and freshwater “mini-estuaries”. ACKNOWLEDGEMENTS Funding for KGI Watershed Nearshore Salmon Habitat Assessment was provided by Pierce County Water Programs with funding assistance from the Washington State Salmon Recovery Funding Board (SRFB; IAC Grant 01-13470) and by Hart Crowser, Inc. The authors wish to recognize these organizations for their support. In particular, we have appreciated the support and encouragement of the Contract Manager, Mr. Dave Renstrom of Pierce County and Mike Ramsey, SRFB Contract Administrator. Also, we would like to thank the KGI Technical Advisory Group (TAG) for their review of our approaches and of the draft report which have added insight and local knowledge to the product. TAG members include: • David Renstrom, Pierce County Public Works and Utilities • Don Haring, Washington Conservation Commission/Washington Department of Fish and Wildlife • Doris Small, Washington Department of Fish and Wildlife • Dave Molenaar, Washington Department of Fish and Wildlife • Ron Teissere, Washington Department of Natural Resources • Russ Ladley, The Puyallup Tribe of Indians Pentec Environmental Page vi 12570-01 July 3, 2003 KEY PENINSULA, GIG HARBOR, AND ISLANDS WATERSHED NEARSHORE SALMON HABITAT ASSESSMENT—DRAFT REPORT INTRODUCTION Background Nearshore habitats in Puget Sound are the focus of increasing attention by biologists, planners, regulators, and resource managers seeking to understand the importance of shorelines in supporting a wide variety of important species. Nearshore habitats span a continuum from uplands, through riparian and intertidal zones, to subtidal areas (Williams et al. 2001). In addition to their obvious direct importance for public use (recreation) and aesthetics, nearshore areas are critical to the life histories of numerous species of birds, mammals, shellfish, forage fish and, perhaps most significantly, salmonids now listed as threatened under the Endangered Species Act (ESA). Newly revised but not yet adopted guidelines for shoreline management under the Washington State Shoreline Management Act (SMA) call for each jurisdiction regulating activities in shorelines of statewide significance to conduct an inventory of its shorelines. Such inventories are to be used in establishing appropriate shoreline use designations, and in identifying high-quality areas that should be protected and those that have a high potential for restoration of former ecological functions.