Wildlife Discipline Report Index-Galena Road MP 6.4-6.9 Environmental Assessment Prepared by: Terri Hawke Snohomish County Public Works December 2015 Title VI and Americans with Disabilities Act (ADA) Information: It is Snohomish County’s policy to assure that no person shall on the grounds of race, color, national origin, or sex as provided by Title VI of the Civil Rights Act of 1964, as amended, be excluded from participation in, be denied the benefits of, or otherwise be discriminated against under any County sponsored program or activity. For questions regarding Snohomish County Public Works’ Title VI Program, or for interpreter or translation services for non-English speakers, or otherwise making materials available in an alternate format, contact the Department Title VI Coordinator via e-mail at [email protected] or phone 425-388-6660. Hearing/speech impaired may call 711. Table of Contents 1 Introduction .......................................................................................................................................... 9 2 Project Description .............................................................................................................................. 11 2.1 Proposed design standards ......................................................................................................... 12 2.2 Design Features ........................................................................................................................... 13 3. Methodology ....................................................................................................................................... 16 3.1 Methods of Analysis .................................................................................................................... 16 4 Affected Environment ......................................................................................................................... 18 4.1 General Habitat Characteristics .................................................................................................. 18 4.2 Wildlife Study Area Habitats and Species .................................................................................. 19 4.2.1 Riparian Zone ...................................................................................................................... 19 4.2.2 Wetlands ............................................................................................................................. 20 4.2.3 Upland Forest ...................................................................................................................... 21 4.2.4 Wildlife Corridors and Connectivity ................................................................................... 22 4.3 Special Status Wildlife Species in Study Area ........................................................................... 24 4.3.1 Presence of Species and Use of Wildlife Habitats in Study Area ....................................... 24 5 Environmental Consequences ............................................................................................................ 43 5.1 Summary ..................................................................................................................................... 43 5.2 Build Alternative ......................................................................................................................... 45 5.2.1 Temporary Effects from Construction ................................................................................ 45 5.2.2 Permanent Effects of Project ............................................................................................... 47 6 Unavoidable Adverse Impacts ............................................................................................................ 53 7 References .......................................................................................................................................... 54 Index-Galena Road MP 6.4-6.9 Wildlife Discipline Report Snohomish County Public Works December 2015 1 Attachment A Photos of Project Area and Wildlife Sign Attachment B Area Impact Plan Sheets Attachment C Species List Attachment D U.S. Forest Service Aquatic Conservation Strategy Index-Galena Road MP 6.4-6.9 Wildlife Discipline Report Snohomish County Public Works December 2015 2 Executive Summary Project Description Snohomish County proposes to relocate approximately one mile of Index-Galena Road from milepost 6.4-6.9. The road is located in T28N R10E in sections 35 and 36. Index-Galena Road parallels the North Fork Skykomish River and a portion of it damaged by high river flows is presently located within the river channel. The proposed project would shift the project area roadway alignment out of the river channel to the south and establish a relocated roadway upslope from the existing damaged roadway. The alignment would transition from the existing Index Galena Road approximately 200 feet east from Trout Creek Bridge #494 (near Milepost 6.1). The relocation would enable the roadway to be elevated above the 100-year flood elevation and channel migration zone for most of the project length and would be landward of the river channel that has formed in the existing roadway alignment. Culverts would be constructed where the roadway crosses non-fish bearing streams and drainage areas. A concrete box culvert vented ford crossing (culvert like structure with potentially a removable top to allow for removal of deposited materials) would be installed in proximity to Station 29+00. The culverts would be sized to convey the 100-year flow and associated debris. A bridge would be constructed over the fish-bearing stream and associated wetland near the north end of the project. Asphalt and other debris would be removed from the river and adjacent riparian areas where the damaged existing roadway is presently located. The decommissioned roadway would then be restored with duff soils salvaged from the project site and planted with ecologically appropriate native species to provide a forested riparian corridor adjacent to the North Fork Skykomish River. In areas where the river flows over the old roadway, roadway debris will be removed where feasible to allow for natural stream channel processes. Methodology Prior to undertaking the field investigation for this report, several sources of existing information were checked for information on potential and known wildlife species and habitats that may be found in the study area. Several site visits to assess wildlife habitat and wildlife presence, and impacts to the habitat were conducted during 2011, 2012, and 2013. Affected Environment The study area is part of the North Cascades physiographic region. The North Cascades mountain range extends from British Columbia south to the Snoqualmie Pass area. The North Cascades consist of jagged peaks with numerous glaciers. This area was formed through a variety of geomorphologic processes including, glacially-carved valleys, colliding terranes, and volcanic activity. Mountain peaks over 10,000 feet steeply plunge to lower elevations of 500 Index-Galena Road MP 6.4-6.9 Wildlife Discipline Report Snohomish County Public Works December 2015 3 feet. The major river valleys include the Snoqualmie, Skykomish, Snohomish, Stillaguamish, Skagit, and Nooksack, which all flow into Puget Sound. The project lies within the North Fork Skykomish River drainage. Environmental Consequences Temporary and permanent impacts would occur throughout the riparian area, mature upland forest, streams, and wetlands. Parts of two wetlands would be permanently filled. The proposed bridge would also shade a small section of wetland. Seven seasonal non-fish bearing streams would be conveyed in culverts and one perennial non-fish bearing stream would flow through a culvert at an armored crossing. Mature trees would be removed to accommodate the relocated road and construction related access to construct walls and rock-filled slopes. Approximately 12.2 acres of mature mixed forest would be cleared. Of this, total approximately 3.3 acres would be permanently impacted for the relocated road alignment roadway prism. Construction related impacts would result in approximately 8.9 acres of long-term temporary buffer impact that would be restored after construction is completed. The entire project area is within U.S. Forest Service designated riparian reserves that are located in the North Fork Skykomish River valley. In addition to trees and understory shrubs, habitat elements within the forest that would be removed include stumps, logs, snags, and boulders. The primary wildlife species that may be affected by this change would be amphibians (including western toads), reptiles, Pacific wrens, bats, pine martens, other small to medium mammals (e.g. bobcat), and several neotropical migrant species and resident birds. Nesting and/or foraging habitat for forest interior birds such as tanagers, thrushes, spotted owls, and Pacific wrens would be lost by clearing. Their nests in adjacent areas would also be more susceptible to predators, such as Stellar’s jays, due to the increased edge effect created by clearing. Short-term temporary loss of nesting areas for neotropical birds and thermal cover for a variety of species would be replaced by the planting of native trees and shrubs in the cleared areas adjacent to the roadway and in the riparian areas along the river. Planting areas in the riparian corridor along the river would provide some protection