Estero Americano Creek Bridge Replacement

Wetland and Riparian Habitat Mitigation and Monitoring Plan

State Route 1 Marin and Sonoma Counties, California 04-SON-1 PM 17.3/21.8 EA 20950

May 2016

For individuals with sensory disabilities, this document can be available in Braille, large print, on audiocassette, or computer disk. To obtain a copy in one of these alternate formats, please call or write to Caltrans, Attn: Greg Pera, Office of Biological Sciences and Permits, 111 Grand Avenue, Oakland, CA 94623-0660; (510) 286-5617 Voice, or use the California Relay Service TTY number, (800) 735- 2929.

Estero Americano Creek Bridge Replacement Habitat Mitigation and Monitoring Plan

1.1 Contents

Chapter 1 Introduction to Project Requiring Mitigation ...... 1 1.1 Proposed Mitigation ...... 1 1.2 Location ...... 1 1.3 Project Description ...... 2 1.4 Environmental Setting ...... 5 1.4.1 Aquatic Functions ...... 6 1.4.2 Habitat Types ...... 7 1.4.3 Hydrology and Topography ...... 7 1.4.4 Soils and Substrate ...... 7 1.4.5 Vegetation ...... 8 1.4.6 Threatened and Endangered Species ...... 9 1.5 Project Impacts that Require Mitigation ...... 9 1.5.1 California Department of Fish and Wildlife Jurisdictional Impacts ...... 10 1.5.2 California Coastal Commission Jurisdictional Impacts ...... 11 1.5.3 North Coast Region Water Quality Control Board Jurisdictional Impacts ...... 11 Chapter 2 Mitigation Project ...... 12 2.1 Objective of Proposed Mitigation ...... 12 2.1.1 Riparian Trees ...... 13 2.1.2 Wetlands and U.S. Waters ...... 13 2.2 Mitigation Site Selection ...... 13 2.3 Mitigation Site Protection Instruments ...... 14 2.4 Baseline Information at Mitigation Sites ...... 14 2.5 Mitigation Habitat Restoration and Establishment ...... 16 2.5.1 Plant Installation Methods ...... 18 2.5.2 Irrigation ...... 19 2.5.3 Weed Control ...... 19 Chapter 3 Performance Standards and Management Plan ...... 20 3.1 Success Criteria ...... 20 3.1.1 Minimum Vegetatation Cover ...... 20 3.1.2 Surface Area of Wetland and Riparian Tree Mitigation ...... 20 3.1.3 Soil Stability ...... 21 3.1.4 Hydric Soil Indicators ...... 21 3.2 Monitoring and Reporting ...... 21 3.3 Offsite Long-term and Adaptive Management Plan ...... 23 3.4 Financial Assurances ...... 23

Appendix

Appendix A Figures Appendix B Project Site Photos Appendix C Mitigation and Planting Plans

Estero Americano Creek Bridge Replacement Habitat Mitigation and Monitoring Plan

List of Abbreviated Terms

Caltrans California Department of Transportation

CEQA California Environmental Qualtiy Act

CDFW California Department of Fish & Wildlife

CNDDB California Natural Diversity Database

ESA environmentally sensitive areas ft foot

LSAA Lake and Streambed Alteration Agreement

PM post mile

RCD Resource Conservation District

RE Resident Engineer sq square

SR State Route

USFWS U.S. Fish and Wildlife Service

NCRWQCB North Coast Regional Water Quality Control Board

Estero Americano Creek Bridge Replacement Habitat Mitigation and Monitoring Plan

Introduction to Project Requiring Mitigation

Chapter 1 Introduction to Project Requiring Mitigation

1.1 Proposed Mitigation

This Habitat Mitigation and Monitoring Plan (HMMP) has been prepared for the California Department of Fish and Wildlife (CDFW), California Coastal Commission (CCC), United States Army Corps of Engineers (USACE), and the North Coast Regional Water Quality Control Board (NCRWQCB), per the conditions of the Lake and Streambed Alteration Agreement, Coastal Development Permit, 404 Wetlands Permit, and Water Quality Certification. It presents the compensatory mitigation for the loss of wetlands and riparian habitat, including impacts to state waters, incurred by the Estero Americano Creek bridge- replacement project on State Route (SR) 1 in Marin and Sonoma Counties, California.

The Estero Americano Creek bridge replacement project (described in Section 1.3) will be mitigated both onsite and offsite: (1) onsite at the bridge project site within the Caltrans Right of Way (ROW) and (2) offsite at the Estero Americano Coastal Preserve. This mitigation and monitoring plan provides details for the wetland creation and riparian replacement planting to be installed onsite at the project location described above and prelimary plans for offsite mitigation at the Estero Americano Coastal Preserve.

The goal of the proposed mitigation is to restore riparian tree and wetland habitats in areas of temporary impact and establish wetland habitat in areas adjacent to permanently impacted wetlands lost resulting from the bridge replacement with comparable habitat. The mitigation is expected to provide equivalent or better functional values for wildlife compared to the existing site conditions and is to be restored and enhanced with the goal of establishing quickly and being self-sustaining after the three-year plant establishment period.

1.2 Location

The Estero Americano Bridge Replacement Project is located in an unincorporated area on the Marin County and Sonoma County line about 1.5 miles east of Valley Ford on SR 1. The project limits stretch from post mile (PM) 50.1 to 50.5 in Marin County and from PM 0.0 to 0.1 in Sonoma County. The project limits lie entirely in the Valley Ford U.S. Geological Survey (USGS) 7.5-minute topographic quadrangle, and within the Americano Creek watershed. The proximity of Americano Creek to the Estero Americano estuary results in the stretch through the proposed project being refered to as Estero Americano Creek. Figure 1 depicts the regional vicinity of the project location and Figure 2 shows the exact location and vicinity of the project.

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1.3 Project Description

The bridge over Estero Americano Creek was originally constructed in 1925 and is at the end of its service life. The roadway and bridge flood periodically in the winter during storm events because of silt aggradation in the creek channel and the low elevation of the road relative to the landscape. Caltrans proposes to replace the existing 146-foot-long, 24-foot- wide bridge with a 266 feet long and 40 feet wide bridge that will be constructed slightly east of the existing alignment. The roadway will also be widened and shifted slightly through the project limits in order to conform to the new bridge. The existing roadway consists of 10- to 11-foot lanes with 0- to 1-foot shoulders. Caltrans proposes to construct 12-foot lanes with 6- foot shoulders with retaining walls extending away from the creek at the ends of all four bridge abutment corners for distances between 100 feet (from the northwest corner of the bridge) and 575 feet (from the southwest corner). Metal beam guard railing will be mounted on the retaining walls. The roadway approaches and bridge will be elevated above the surrounding landscape. Roadway embankments with 2:1 side slopes will be constructed along the remainder of the roadway from the ends of the retaining walls to the project limits. Components of the project are shown in Figure 3.

The new, longer bridge will ameliorate flooding at the project location and create more space for wildlife passage beneath the roadway. Construction of the retaining walls will likely reduce the frequency of wildlife accessing and crossing the SR 1 roadway, thereby reducing wildlife mortality.

The project’s construction activities will occur within a six-acre project footprint entirely within the Caltrans right-of-way. Two areas within the right-of-way and within the project limits will be delineated with ESA-type fencing to prohibit access and preserve natural resources. One-way traffic control will be required throughout the project, and occasional full lane closures will be needed.

Construction of the new bridge will require temporary water diversion structures within waters of the US that will be removed from the Estero Americano Creek channel prior to each rainy season during the two year period of bridge construction.

The project footprint is defined as the areas that will be directly affected by the proposed project. It is the maximum extent of ground-disturbing activities from the various construction actions. The total area of the project footprint is approximately 6.0 acres (ac). All construction activities, including site preparation, staging, access, and detours, will occur within the project footprint, as shown on Figure 3.

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Construction will occur within two construction seasons (April 15 to November 1), with tree removal occurring as a pre-construction activity during autumn of the preceding construction season (September 1 to October 15) to allow for trees to be cut to stumps and removed outside of the bird nesting period (February through August). Table A-1 in Appendix A lists the major construction activities in order of sequence, together with associated construction equipment, work season, and duration.

Prior to construction, high-visibility orange ESA fencing and wildlife exclusion fencing (WEF) will be installed along the perimeter of the work areas adjacent to sensitive habitats to clearly delineate the extent of the construction area and to prevent the California red-legged frog (Rana draytonii; CRLF) from entering the construction area (Figure 5). The project’s construction specifications will include language regarding ESA and WEF fencing installation procedures, acceptable fencing material, prohibited construction-related vehicle operation, material and equipment storage, and other surface-disturbing activities within sensitive areas. Fencing will be inspected and maintained throughout all construction activity work periods.

Prior to construction activities in the areas of Estero Americano Creek, a water diversion structure will be installed, consisting of the following: an upstream coffer dam constructed of gravel bags lined with an impermeable barrier, a pipe to convey stream flow through the construction area, and an additional coffer dam supported by a sheet-pile wall on the downstream end to prevent backflow into the construction area. Once the water diversion system has been established, dewatering will occur to facilitate access into the construction area. The entire system will be located within the project footprint and Caltrans ROW, and the exact dimension and location of the structure will be determined by the contractor.

Vegetation will be cleared only when necessary and will be cut above original ground level except in areas that will be excavated for permanent construction. This will allow plants that reproduce vegetatively to resprout after construction. All clearing and grubbing will be completed using backhoes, excavators and hand tools or small mechanical tools, such as chainsaws, shovels and picks. In addition, a dump truck will be used to haul the debris.

Implementing general and species-specific avoidance and minimization measures (AMMs) and BMPs will avoid or minimize potential direct or indirect effects for plants or wildlife species outside of the project footprint.

This project will be constructed in three stages:

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 Stage 1: The majority of vegetation within the project footprint (i.e., the area within which all construction activities will occur, as shown on Figure 4) will be cleared, above ground level, prior to conducting any ground-disturbing activities. This major vegetation clearing will be done between September 1 and October 15, the year before construction begins.  Stage 2: Prior to groundbreaking, Caltrans will shift all traffic onto the southbound lane of the existing bridge. The northbound lane will be used for staging and to construct the northbound lane of the new bridge and new roadway approaches east of the existing bridge. Caltrans will also modify the existing roadway and install embankments at both ends of the current bridge approaches to accommodate the one-way traffic control. During Stage 1 the west side of the project footprint will be delinated as an ESA and only limited activities will be allowed. A temporary access road, no more than 15 feet in width, will be constructed as needed within the west side of the project footprint, across the north bank of Estero Americano Creek, to accommodate construction vehicles and for the water diversion construction and bridge construction. No work, outside of construction of and use of the access road, installation of temporary signal poles, and establishment of ESA type fencing will occur in the west side of the project footprint. Caltrans will re-grade and rehabilitate all temporarily disturbed areas in the east side of the project footprint. The existing wetland ditches that currently line SR 1 will be restored or established within the project limits on the east side at the end of this construction stage. All disturbed areas along the east side of the roadside will be reseeded with a native hydroseed mix, with the exception of an area for an access road to the creek channel, and all construction materials will be removed from the site.  Stage 3: Following construction of the first half of the bridge, Caltrans will shift traffic onto the new bridge and northbound traffic lane and proceed to remove the existing bridge. The second half of the new bridge and roadway will then be constructed from areas within the creek and on the existing SR 1 southbound lane and embankment. A temporary access road, up to 15 feet in width, will be constructed as needed west of the new bridge structure and east of the western edge of the existing, old, roadbed, to accommodate construction vehicles and for the water diversion construction and bridge construction. No work will occur in the east side of the project footprint, except to maintain the revegetated areas as needed, and this area will be protected with ESA type fencing. Caltrans will re-grade and rehabilitate all temporarily disturbed areas in the west side of the project footprint. The existing wetland ditches that currently line SR 1 will be restored or established within the project limits on the west side at the end of this construction stage (Figure 4). All disturbed areas along the west side of the roadside will be reseeded with a native hydroseed mix, and all construction materials will be removed

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from this site. Riparian trees and shrubs will be replanted within the Estero Americano Creek corridor to satisfy a portion of required mitigation.

Construction access to the proposed project site will be provided via the existing roadway and through access roads within Caltrans’ ROW. Since all work will occur in the ROW, no permanent or temporary construction easements will be required for this project.

Material and equipment staging will occur primarily on the roadway, in the temporarily closed southbound or northbound lane. Additional staging of materials and equipment, if needed, will occur within the Caltrans right of way in the southernmost extent of the project footprint. Staging areas will allow for equipment storage, equipment maintenance, and construction material storage during construction.

The project will require one-way traffic control. Poles for temporary signals will be 35-ft-long Class 5 wooden poles. To install the poles, 6-ft-deep holes will be drilled with a rig-mounted drill and a crane will place the wooden poles into the holes. The location of the poles will be in ruderal grassland and areas of cut willows that will be temporarily disturbed due to construction activities.

All construction-related materials, including WEF and ESA fencing, will be removed, and cleaning and maintenance will be performed by Caltrans or by approved contractors. after all construction is completed. Standard Caltrans practices for cleaning, repairing, and otherwise maintaining SR 1 will be followed.

1.4 Environmental Setting

The project site crosses Estero Americano Creek upstream of where the creek transitions into the Estero Americano near Valley Ford (Gold Ridge RCD 2007). The Estero Americano watershed covers 49 square miles and provides habitat for numerous fish and wildlife species, including species of special concern (Gold Ridge RCD 2007). The Estero Americano has been categorized as a Critical Coastal Area by the State of California and is part of a Category 1 Priority Watershed (Gold Ridge RCD 2007).

The Estero Americano floodplain is a sensitive natural area, because the Estero Americano empties into Bodega Bay, supports various protected plant and animal species, is lined with wetlands, and is largely undeveloped. Grazing and dairy farming are the primary land uses in the Estero Americano Watershed (CCC 2006). The Estero Americano is also a 303(d) impaired water body according to the U.S. Environmental Protection Agency (USEPA) because of nutrient and sediment deposition into the water way (State Water Resources

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Control Board [SWRCB] 2010). Water bodies designated as 303(d) are water bodies that do not meet water quality objectives and are impaired to the point that they do not support their beneficial uses, which for the Estero Americano is cold freshwater habitat for fish, shellfish, and wildlife protection and propagation (SWRCB 2010). Estero Americano Creek and its tributaries are considered to be in a degraded state (Gold Ridge RCD 2007). Efforts are underway to improve water quality in the watershed through sediment reduction programs (Gold Ridge RCD 2007).

The northwestern, northeastern, and southwestern areas around the project site have been seeded with crops for forage; the northeastern parcel is actively disked and tilled. The southeastern portion of the project area adjacent to the project limits is primarily grazed by sheep and is not tilled. There are also ditches within the southeastern parcel that have been constructed perpendicular to the road; the purpose of these ditches is unknown. The vegetation within the ROW consists of wetland species in the ditches and annual grasses elsewhere. Willows (Salix spp.) and blackberries (Rubus spp.) are abundant along Estero Americano Creek and are present in the roadside ditches nearest the creek. The primary natural resources, including willow thickets, rare plants, wetlands ditches, and other waters of the U.S. within the project footprint are mapped in Appendix A, Figure 4. Project site photos are included in Appendix B.

1.4.1 Aquatic Functions Estero Americano Creek traverses from east to west below the existing concrete bridge structure on SR 1 and flows towards Bodega Bay and the Gulf of the Farallones National Marine Sanctuary (CCC 2006, Gold Ridge RCD 2007). The proximity of Americano Creek to the Estero Americano estuary results in the stretch through the proposed project being refered to as Estero Americano Creek. Estero Americano is a relatively undisturbed coastal estuary, roughly 300-1000 feet wide that extends 4.0 miles from the Pacific Ocean inland the town of Valley Ford. Americano Creek is roughly 7.6 miles and is the largest tributary draining into the 39 squre-mile Estero Americano watershed. Approximately 31 miles of USGS ephemeral streams and an additional 56 miles of smaller seasonal streams are present in the watershed (Gold ridge RCD 2007). Americano Creek forms the boundary between Marin and Sonoma Counties. Dense riparian habitat is present along the creek west of SR 1 and lies adjacent to upland and mesic grassland communities. The creek banks immediately upstream of the bridge (east side of SR 1) support a small patch of riparian habitat and a riparian wetland. There are excavated roadside ditches parallel SR 1 that connect to Americano Creek. Portions of these ditches have developed into high functioning wetland ditches and have been

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delineated as U.S. wetlands while the remaining portions have been delineated as other waters of the U.S.

1.4.2 Habitat Types The project area itself does not intersect any specially designated habitats of concern, such as a CDFW natural community of conservation concern or endangered species critical habitat. There are wetlands and waters of the U.S. and State within the project area and project footprint, which provide habitat to common and special-status species and also function to filter water and protect against storm surges. Within the project footprint there is 0.75 acre of wetlands and waters of the U.S., State and 1.1 acres of riparian trees.

1.4.3 Hydrology and Topography Although Estero Americano Creek was once a perennial stream, it and other streams in the Estero Americano Creek Watershed are now intermittent in most years because of sediment deposition in the watershed (Smith et al. 1989, Gold Ridge RCD 2007). The project area is located within the Bodega Bay Hydrologic Unit (Hydrologic Unit Code [HUC] 18010111) (USEPA 2014). The Estero Americano Creek Watershed has changed from its historic condition because of agricultural land use, instances of unmanaged livestock grazing, and historical potato farming, which was common between 1850 and 1953 (Gold Ridge RCD 2007). These practices have resulted in excessive sediment deposition to the Estero Americano (MCWP 2014), which has contributed to stream channel aggradation, which in turn exacerbates local flooding problems near Bloomfield and Valley Ford (Buell 1988, Gold Ridge RCD 2007). The supply of fine sediment to Estero Americano Creek significantly exceeds the carrying capacity of the stream (Buell 1988, Gold Ridge RCD 2007).

The project is located in the Coastal Hills – Santa Rosa Plain ecological subsection of the Northern California Coast Region (The Encyclopedia of Earth [EOE] 2009). The hills are moderately steep and contain sediments that have eroded to expose rock complexes and create nonmarine terraces and floodplains. The main geomorphic process on the coastal plain and nonmarine terraces is fluvial erosion, which is also active on alluvial plains (EOE 2009). Elevations within the project area range from approximately 24 to 34 feet above sea level.

1.4.4 Soils and Substrate The information on soils in the BSA was obtained from the Natural Resources Conservation Service (NRCS) Web Soil Survey Application (NRCS 2013a, Caltrans 2014a) and from official soil series descriptions (NRCS 2013b, Caltrans 2014a). The soils within vicintiy of the project consist of Blucher-Cole complex (2 to 5 percent slopes), Blucher fine sandy loam, overwash (0 to 2 percent slopes), Tomales-Steinbeck loams (5 to 15 percent slopes), and

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Steinbeck loam (2 to 9 percent slopes) (NRCS 2013a, Caltrans 2014a). Both Blucher soil types are poorly drained and partially hydric (NRCS 2013b, Caltrans 2014a). Tomales- Steinbeck loams are moderately well drained and non-hydric soils, while Steinbeck loams are moderately well drained and partially hydric (NRCS 2013b, Caltrans 2014a).

1.4.5 Vegetation At a coarse level, the vegetation within the project area is largely classified as moderate grasslands, Central Coast riparian forest, and cultivated agriculture (Bay Area Open Space Council [BAOSC] 2011). Moderate grasslands are grasslands dominated by annuals, with varying amounts of perennials, and where July maximum temperatures range between 71.6 and 78.8°F. Central Coast riparian forest includes stands of willows, cottonwood, sycamores, and other trees along streams (BAOSC 2011). Cultivated agriculture includes areas where row crops, vineyards, orchards, and other crops that require soil tillage are grown (BAOSC 2011). As observed during site visits, the land parcels surrounding the roadway are used for sheep grazing and cultivation, including corn and oats production. The roadway is flanked by wetland ditches populated by blackberry, poison hemlock (Conium spp.), teasel (Dipsacus spp.), and willows. Estero Americano Creek supports a riparian corridor of willows and wetlands within the project footprint and is classified as Central Coast riparian forest (BAOSC 2011). The following, more specific information on the vegetation in the BSA is primarily derived from Caltrans’ rare plant report that was prepared for this project (Caltrans 2014a).

More specifically, the vegetation types within 30 acres surrounding the project footprint (Figure 3-1), which also contains agriculture and urban surface area, is comprised of fourteen percent Red Willow Thickets (Salix laevigata Alliance), two percent Wet Meadows Alliance, four percent Poison Hemlock Patches-Himalayan/California Blackberry Brambles (Conium maculatum Semi-natural Stands-Rubus armeniacus Semi-natural Stands/Rubus ursinus Alliance), one percent Annual Semaphore Grass Fields (Pleuropogon californicus Alliance), ninteen percent Perennial Rye Grass Fields (Lolium perenne Semi-natural Stands), and fifteen percent Annual Grasses and Forbs (mesic and upland).

Floristic plant surveys identified three potential rare plant species within the project area, including purple-stemmed checkerbloom (Sidalcea malviflora ssp. purpurea), Johnny nip (Castilleja ambigua ssp. ambigua), and Contra Costa goldfields. Purple-stemmed checkerbloom was observed within Caltrans’ ROW near the roadway shoulder north and east of the bridge at the northern end of the project limits. The second potential rare plant species identified in the project area was Johnny nip (Castilleja ambigua ssp. ambigua), which like purple-stemmed checkerbloom is included on CNPS’ rare plant inventory but is not state or

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federally listed. The federally endangered Contra Costa goldfields was also observed within the southeastern portion of the project area but not within the project footprint.

1.4.6 Threatened and Endangered Species Federal threatened and endangered species do occur or have the potential to occur within the general project vicinity and project footprint. The USFWS concluded that the project may affect but is not likely to adversely affect Myrtle’s silverspot butterfly (Speyeria zeren myrtleae). The USFWS concluded that the project may affect and is likely to adversely affect the California red-legged frog (Rana draytonii). Additionally,USFWS concluded that Contra Costa goldfields (Lasthenia conjugens) may be affected by the project. Other listed species are unlikely to occur in the project area because of a lack of suitable habitat and because the project is outside the species’ known elevation or range. Species unlikely to occur in the BSA include listed fish species, including the state and federally endangered Central California Coast coho salmon (Oncorhynchus kisutch) and state threatened Central California Coast steelhead (Oncorhynchus mykiss), since Estero Americano Creek is too intermittent at the project location to consistently support salmonids. Estero Americano Creek is presently not known to support fish resources above tidewater (Smith et al. 1989, Gold Ridge RCD 2007); the current tidal extent of the Estero Americano is up to four miles inland (Marin County Watershed Program [MCWP] 2014).

1.5 Project Impacts that Require Mitigation

On December 15, 2014, Caltrans adopted an Initial Study with Negative Declaration for the project pursuant to the California Environment Quality Act (CEQA). Because of the proposed vegetation clearing, Caltrans made CEQA commitments to compensate for the loss of riparian habitat and upland habitat with plant and tree replantings on-site at the bridge project site and off-site as needed. These commitments were outlined in the final Initial Study with Negative Declation of December 2014 to compensate for both biological and visual impacts.

The proposed bridge construction is anticipated to result in temporary and permanent impacts to 3.9 acres of upland grassland that serve as dispersal habitat for California red-legged frog, 1.1 acres of riparian trees that are primarily willow thickets, 0.406 acres of wetlands that are primarliy roadside ditches, and 0.33 acre of waters of the U.S that are within the banks of Estero Americano Creek. The natural resources impacted within the project footprint are mapped on Figure 5. Details of the agency jurisdiction and nature of these impacts are described in the following sections.

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1.5.1 California Department of Fish and Wildlife Jurisdictional Impacts CDFW jurisdictional areas within the proposed project footprint include the north and south banks of Estero Americano Creek, including the trees and vegetation up to the top of the creek bank and to the outer (landward) edge of the vegetation’s dripline as it extends up wetland ditches hydraulically connected to Estero Americano Creek. CDFW jurisdiction was evaluated in the field during rare plant surveys, tree surveys, and wetland mapping efforts and mapped using aerial photographs and Global Positioning System (GPS) coverage within the project footprint. CDFW jurisdiction within the project footprint consists of a total of approximately 1.1 ac of mixed riparian trees, most of which are willow (Salix spp.) along both the north and south banks of Estero Americano Creek (140 linear feet) that extend into hydraulically connected wetland ditches perpendicular to the creek (1,600 linear feet). In addition to willow thickets, Oregon ash and Klamath Hawthorne trees will be impacted (Table1).

Table 1 Trees to be Removed within Construction Area

Coverage Diameter at Breast Number Tree Area Height (dbh)b of No.a Species Scientific Name (acres) (inches) Stemsb 1 Red willow Salix laevigata 1.08 - - 2 Arroyo willow Salix lasiolepis 0.06 - - 3 Oregon ash Fraxinus latifolia - 5.5, 6.0, 6.0 3 4 Oregon ash Fraxinus latifolia - 4.0, 3.5, 2.0 3

5 Oregon ash Fraxinus latifolia - 4.0, 4.0, 3.0, 2.5 4

6 Oregon ash Fraxinus latifolia - 5.0, 6.0, 5.0, 3.5 4

7 Klamath hawthorn Crataegus gaylussacia - 4.0, 4.5, 4.5, 4.0 4 8 Klamath hawthorn Crataegus gaylussacia - 4.0, 4.0 2 9 Klamath hawthorn Crataegus gaylussacia - 4.0, 4.0 2 10 Klamath hawthorn Crataegus gaylussacia - 4.0 1 Notes: a Tree numbers correspond to the numbers on Figure 4 (see Appendix A). b In the case of multiple-stemmed trees, the diameter of each of the stems is reported.

Project components within CDFW jurisdiction include the widened, re-aligned, and elevated roadway, retaining wall, bridge abutments, bridge support pilings, and the bridge structure. Site preparation and vegetation removal will occur within CDFW jurisdictional areas during the year prior to constuction. Since riparian tree removal will occur a year or two prior to habitat restoration and tree re-planting on-site, the impacts to riparian trees are considered permanent.

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1.5.2 California Coastal Commission Jurisdictional Impacts Construction activities are expected to result in permanent impacts to wetlands and riparian trees within the project site due to the timing of this multi-year construction schedule. A total of 0.406 acres of wetlands located in ditches on all four corners of the existing bridge along SR 1 and perpendicular to Estero Americano Creek will be impacted. These wetlands will be displaced by the roadway footprint and construction activities. A total of approximately 1.1 ac of mixed riparian trees, most of which are willow (Salix spp.), growing along both the north and south banks of Estero Americano Creek and in hydraulically connected wetland ditches perpendicular to the creek will be cut, resulting in a permanent impact to this habitat.

1.5.3 Army Corps of Engineers Jurisdictional Impacts Delineation of waters of the U.S. for Americano Creek, vegetation types, and rare plant surveys were conducted May 21, May 31, August 14, 2013, and April 24, and September 29, 2014. Delineation of waters of the U.S. for Americano Creek was verified by the USACE as documented in their June 16, 2015 letter. Figure 5 shows the portion of the creek that was verified as waters of the U.S. by USACE within the project area and project footprint. Project construction will result in a total of 0.262 acres of temporary impacts and 0.144 acres of permanent impacts to USACE jurisdictional wetlands. These areas of USACE jurisdictional wetlands are also jurisdictional for CCC. Additionally, there are 0.33 acre of temporary impacts to the U.S. waters in Estero Americano Creek that will be fully restored after construction.

1.5.4 North Coast Region Water Quality Control Board Jurisdictional Impacts Construction activities are expected to result in temporary and permanent impacts to waters of Estero Americano Creek. A temporary work pad constructed from timber will be installed in areas of proposed temporary impacts to minimize impacts to aquatic habitat and water quality during construction. The work pads and additional construction activities are expected to temporarily displace a total of approximately 0.33 acres of state waters within the Estero Americano Creek channel and 0.262 acre of wetland ditches and swales along the roadway at the bridge construction site.

Proposed construction at the bridge will permanently impact a total of approximately 0.144 acres of wetlands. A total of 0.262 acre of wetlands will be temporarily displaced by construction activities A total of approximately 1.1 ac of mixed riparian trees, most of which are willow (Salix spp.), growing along both the north and south banks of Estero Americano Creek and in hydraulically connected wetland ditches perpendicular to the creek will be cut, resulting in a permanent impact to this habitat.

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Chapter 2 Mitigation Project

2.1 Objective of Proposed Mitigation

The goal of the proposed mitigation is to compensate for permanent and temporary impacts to CDFW, CCC, USACE, and NCRWQCB jurisdictional resources. Caltrans will compensate for impacts to riparian and wetland habitat resulting from construction activities associated with the Estero Americano Creek bridge replacement project. To meet this goal, Caltrans proposes to replace lost habitat with comparable habitat having a similar species composition and density. The mitigation proposed will include an onsite component and an offsite component. Table 2-1 summarizes the project mitigation requirements from regulatory agencies, and details the habitat types impacted, the type of impact, and the total project mitigation requirement for the project.

Table 2-1. Project Mitigation Requirements from Regulatory Agencies

Regulatory Riparian Trees, Permanent Wetland, Temporary Wetland, Permanent Agency Impacts Impacts Impacts Requiring Habitat Acres of Acres of Acres of Acres of Acres of Acres of Mitigation Impact Required Impact Required Impact Required Mitigation Mitigation Mitigation U.S. Army - - 0.144 0.29 0.262 0.36 Corps of Engineers

North Coast 1.1 3.3 0.144 0.57 0.262 1.04 Regional Water Quality Control Board California 1.1 3.3 - - - - Department of Fish and Wildlife

California 1.1 3.3 - - 0.406 1.61 Coastal Commission TOTAL PROJECT 3.3 acres - 1.6 acres MITGATION REQUIREMENT

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2.1.1 Riparian Trees Onsite A total of 1.22 acres of riparian willows will be replanted on-site from salvaged willow tree cuttings collected onsite prior to construction. The salvaged willow cuttings will be maintained during construction to ensure their viability when used for re-establishment of the riparian tree community onsite. The use of salvaged cuttings from pre-construction tree removal ensures the genetic lineage of the native plant community is retained after restoration. Onsite mitigation site plantings are presented in Appendix C.

Offsite The remaining balance of total project mitigation obligation forriparian willows will be planned for off-site mitigation in coastal riparian corridors at the Estero Americano Coastal Preserve. The Wildlands Conservancy have identified approximately 2.2 acres that could be suitable for habitat restoration in riparian corridors that would support willow plantings at the Estero Americano Coastal Preserve. A detailed scope of work for the riparian tree plantings at the offsite mitigation site is in development and will be provided to agency partners for approval.

2.1.2 Wetlands and U.S. Waters Onsite A total of 0.36 acre of wetlands will be estbalished in areas adjacent to permanent wetlands impacts, and 0.29 acre of wetlands will be restored in areas where temproary impacts occurred, for a total of 0.65 acre of wetlands re-created onsite. Onsite mitigation site final grading contours and hydroseed mix species for wetlands restoration and establishment are presented in Appendix C.

Offsite The remaining balance of the total wetland mitigation obligation for the project for wetlands restoration and establishment will be planned for off-site mitigation at the Estero Americano Coastal Preserve. The Wildlands Conservancy have identified areas suitable for wetland enhancement, restoration, or establishment at the Estero Americano Coastal Preserve. A detailed scope of work for the offsite mitigation of wetlands in development and will be provided to agency partners for approval.

2.2 Mitigation Site Selection

The onsite mitigation at the project site was selected based on its ability to support restoration and establishment of in-kind habitat impacted and its protection as State-owned lands.

Estero Americano Creek Bridge Replacement Habitat Mitigation and Monitoring Plan 13

Sufficient area exists post-construction to support the restoration and establishment of wetlands and riparian trees with a 1:1 replacement ratio or greater.

The selection of the Estero Americano Coastal Preserve as the offsite habitat mitigation site was made after an exhaustive search for mitigation partners throughout Sonoma and Marin Counties. This site was the closest in proximity to the project site, currently supports in-kind wetland and riparian habitats, and is hydraulically connected downstream through Americano Creek. The owners of the site, the non-profit The Wildlands Conservancy, are supportive of habitat improvements to the newly acquired conservation area, and the area is protected in perpetuity under a conservation easement held by the Sonoma County Agricultural Preservation and Open Space District to ensure the continuation and improvement of the conservation values at the site.

2.3 Mitigation Site Protection Instruments

The onsite mitigation at the Estero Americano Creek bridge is entirely within State-owned lands within the Caltrans ROW. The habitat mitigation will be protected in perpetuity within the ROW.

The conservation values at the Estero Americano Coastal Preserve are protected in perpetuity through an existing conservation easement. The land is owned by the non-profit organization The Wildlands Conservancy (TWC). The land was purchased with public monies in December 2015, for the purpose of habitat conservation and is protected in-perpetuity through an existing conservation easement held by the Sonoma County Agricultural Preservation and Open Space District (Sonoma County). Caltrans plans to secure an additional conservation easement with The Wildlands Conservancy to protect the wetland and riparian restoration and establishment work for its offsite mitigation in perpetuity.

2.4 Baseline Information at Mitigation Sites

Estero Americano Creek was once a perennial stream, and this creek and other streams in the Estero Americano Watershed are now intermittent in most years because of sediment deposition in the watershed (Smith et al. 1989, Gold Ridge RCD 2007). Estero Americano Creek is presently not known to support fish resources above tidewater (Smith et al. 1989, Gold Ridge RCD 2007); the current tidal extent of the Estero Americano is up to four miles inland, which is outside the BSA (Marin County Watershed Program [MCWP] 2014). The Estero Americano Creek Watershed has changed from its historic condition because of agricultural land use, instances of unmanaged livestock grazing, and historical potato farming, which was common between 1850 and 1953 (Gold Ridge RCD 2007). These practices have

Estero Americano Creek Bridge Replacement Habitat Mitigation and Monitoring Plan 14

resulted in excessive sediment deposition to the Estero (MCWP 2014), which has contributed to stream channel aggradation, which in turn exacerbates local flooding problems near Bloomfield and Valley Ford (Buell 1988, Gold Ridge RCD 2007). The supply of fine sediment to Estero Americano Creek significantly exceeds the carrying capacity of the stream (Buell 1988, Gold Ridge RCD 2007).

Onsite The predominant vegetative communities that are present at the Estero Americano Creek bridge construction site are riparian and upland annual grassland. A mature riparian corridor is present along the margins and banks of the creek. Within the project boundaries at Estero Americano Creek, the predominant vegetative community is a well-developed mixed willow thicket riparian corridor, conisting of red willow and arroyo willow, with intermittent patches of other riparian tree species, such as Oregon ash and Klamath hawthorne. The flood plain and wetland ditches along Estero Americano Creek in the project site also support stands of blackberry (Rubus spp.) and ruderal grasslands. A delineation of wetlands and waters of the U.S. at the Estero Americano Creek is included in Appendix A.

Offsite The Estero Americano Coastal Preserve is approximately 547.85 acres of rolling grasslands and coastal bluffs bordered to the south by the waters of the Estero de Americano and the Pacific Ocean coastline to the west. It is one of the most biologically important areas in Sonoma and Marin Counties as it contains a diverse assemblage of wetland communites and estuarine habitats and is important habitat for migratory birds in the Pacific Flyway. The location of the site provides excellent habitat connectivity for many species as it is adjacent to, or in close proximity to, the Sonoma Land Trust’s Estero Americano Preserve, Shorttail Gulch and Doran Beach Regional Park, Bodega Head (Sonoma County Park), the Greater Farallones National Marine Sanctuary, and the Estero Americano State Marine Recreational Management Area. The property is currently used to for livestock grazing, primarily cattle, and has several residential and agricultural support buildings onsite. Natural valleys which could support healthy wetland and riparian habitats are degraded. Severe erosion has resulted in incised creek channels that are too steep and unstable to support vegetation in many areas. Additionally, during a site visit on March 10, 2016, runoff flowing through the gullies was observed to be extremely turbid, likely as a result of active sediment erosion. There are many areas within the site that could benefit from wetland and riparian habitat improvements.

Estero Americano Creek Bridge Replacement Habitat Mitigation and Monitoring Plan 15

2.5 Mitigation Habitat Restoration and Establishment

This project will restore approximately 1.6 acres of wetland habitat and 3.3 acres of riparian trees in total, both through on-site and off-site mitigation. We are planning to restore or establish 0.65 acre of wetlands oniste, and 0.95 acre offsite. Approximately 1.1 acres of riparian trees will be restored onsite, and the remaining 2.2 acres will be restored or established offsite.

Onsite Mitigation will be implemented onsite as a final stage in bridge construction, restoring 1.1 acres of riparian trees, restoring 0.29 acre of wetlands in areas of temporary wetland impacts, and re-establishing 0.36 acre of wetlands adjacent to areas of permanent wetland impacts. Non-compensatory mitigation measures have been incorporated into the project to reduce potential impacts to habitat and water quality, including erosion and sediment control Best Management Practices (BMPs). Following the completion of construction, all embankment and excavation slopes and other disturbed areas will be treated with these erosion control materials. Existing contours will be returned to their pre-construction condition at the end of project activities to the extent practicable and will then be hydroseeded using a site specific mixture.

Wetlands will be restored in areas of temporary impact and established in areas of permanent impact onsite through re-grading of the final site elevation to match pre-existing conditions, and contouring to create an inter-connected chain of pocket wetland patches linked by a wetland channel that leads to the Estero Americano Creek channel. These areas will then be treated with a wetland-specific hydroseed mix developed for this project.

Hydro-seeding of native grasses and shrubs will occur on all reconstructed wetland areas, upland areas, and embankments and will be appropriate for the habitat type at each location (see Tables 2-2 and 2-3).

The onsite replacement of native riparian trees will employ salvaged willow that were removed prior to construction to ensure an identical, watershed-specific lineage of these native willow species, which will restore and enhance the creek channel. Willow stakes will be harvested from the site during pre-construction tree removal and salvaged, stored, and maintained for planting at the final stages of bridge construction to restore temporarily and permanently impacted areas. Willow stakes will be planted to establish thickets that will cover approximately 1.1 acres or more along Estero Americano Creek and along restored and

Estero Americano Creek Bridge Replacement Habitat Mitigation and Monitoring Plan 16

established wetlands. Restoring creek and wetland corridors with increased canopy cover will reduce water temperature conditions and increase overall habitat quality.

Offsite The additional offsite mitigation will revegetate 2.2 acres of riparian trees and restore or establish 0.95 acre of wetlands at locations to be determined at the Estero Americano Coastal Preserve. A complete scope of work for offsite mitigaiton is in development with agency partners, TWC, and Sonoma County. This scope of work for the offsite mitigation work plan will be included in a future conservation easement with TWC to oversee the work and protect the mitigation in perpetuity. A detailed scope of work for the riparian tree plantings at the offsite mitigation site is in development and will be provided to agency partners for approval.

Table 2-2 Erosion Control Seed Mix Type 1 for On-site Riparian/Upland Habitat

Pounds Pure Live Seed Per Common Name Scientific Name Acre (Slope Measurement)

Bicolor Lupine Lupinus bicolor 5

California Brome Bromus carinatus 8

California Goldfields Lasthenia californica 1.5

California Poppy Eschscholzia californica 3

Coastal Tidytips Layia platyglossa 3

Coyote Brush Baccharis pilularis 0.15

Narrow leaf milkweed Asclepias fascicularis 1

Western dog violet Vioal adunca 1

Nodding needlegrass Nassella cernua 7

Purple needlegrass Nassella pulchra 10

Small Fescue Vulpia microstachys 6

Tomcat Clover Trifolium wildenovii 5

Western Yarrow Achillea millefolium 1

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Table 2-3 Erosion Control Seed Mix Type 2 for On-site Wetland Habitat

Pounds Pure Live Seed Per Common Name Scientific Name Acre (Slope Measurement)

Baltic rush Juncus balticus 2

Blue Wildrye Elymus glaucus 2

Creeping Wildrye Leymus tricoides 8

Douglas Mugwort Artemesia douglasiana 1

Santa Barbara Sedge Carex barbarae dewey 8

Small Fescue Vulpia microstachys 5

Toad Rush Juncus bufonius 2

2.5.1 Plant Installation Methods All recommended riparian trees and plants, to the extent possible, will be installed in the fall or early winter to optimize plant survival and growth. The previously salvaged on-site willow cuttings will be installed between November and February. Willow planting will consist of Department Furnished willows contract grown from material harvested on-site prior to construction. These willows will be rooted out for one to two years prior to installation in 4x4x14” Min. deep pots. Planting will consist of preparing 8-12” Dia. by 18” deep planting holes which will be back filled with a mix of soil amendment (Compost) and native material. A final layer of basin mulch (wood chips) will be added to help retain moisture and prevent weed growth. Willow plantings will be located at appropriate locations in accordance with the design details (Appendix C). If the quantity of salvaged willow is not adequate, or its survival is compromised during the dry months, additional willow cuttings will be obtained from onsite thickets protected during construction by ESA-type fencing. Typical details on planting methods are provided in Appendix C.

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Table 2-4 Noxious Weed Species as Defined by the California Department of Food and Agriculture Botanical Name Common Name Arundo Donax Giant Reed Centaurea solstitialis Yellow star thistle Chondrilla juncea Skeletonweed Cynara cardunculus Artichoke Thistle Cytisus scoparius Scotch Broom Dittrichia graveolens Stinkwort Foeniculum vulgare Fennel Genista monspessulana French Broom Bulbous canarygrass Phalaris Aquatica Spartium junceum Spanish Broom Xanthium spinosum Spiny Cocklebur

2.5.2 Irrigation All plantings will be watered at the time of planting and will receive additional water thereafter during the plant establishment period. Irrigation details are currently being developed by Caltrans and will vary based on site specific conditions at each location. The bridge site plantings will either be hand-watered or irrigated using an irrigation system.

Regardless of the irrigation method used, the goal will be to provide the necessary water to successfully establish deep-rooted plants that will quickly be able to survive on their own without supplemental watering. The objective is to wean the plants off of supplemental water within the three year plant establishment period. Doing so will ensure that the plants have adapted to the site and will be self-sustaining thereafter. Compost placed in the soil hole at the time of planting and mulch applied around the base of the plants will help retain moisture between waterings.

2.5.3 Weed Control Noxious weed species, as defined by the California Department of Food and Agriculture (see Table 2-4), around individual plant basins at the mitigation site will be controlled by hand pulling for the 3 year plant establishment period and suppressed by placement of wood chip mulch around each plant. The mulch will be installed to a depth of three inches within each plant’s basin.

Estero Americano Creek Bridge Replacement Habitat Mitigation and Monitoring Plan 19

Chapter 3 Performance Standards and Management Plan

The performance standards, or success criteria, monitoring plans are based on: (1) the conditions in the CDFW Lake and Streambed Alteration Agreement and NCRWQCB 401 Water Quality Certification, (2) the applicable "Uniform Performance Standards For Compensatory Mitigation Requirements (12505‐SPD)" and the accompanying table (12505.1) provided by USACE, (3) analysis of previous Caltrans mitigation projects, and (3) pre- construction conditions of the impacted riparian habitat. Details are provided below for onsite mitigation. A detailed plan with monitoring schedules, performance standards, and a management plan for offsite mitigation is in development and will be provided to agency partners for approval.

3.1 Success Criteria

Mitigation success criteria in all on-site and off-site restoration areas consist of, (1) minimum vegetation cover, (2) a minimum surface area acreage of habitats restored, (3) verification of mitigation feature soil stability, and (4) verification of hydric soil indicators. Success criteria are outlined in project permits and described below.

3.1.1 Minimum Vegetatation Cover During the three-year plant establishment period, the installation contractor and/or its designee will replace dead or dying plants during routine maintenance activities. For riparian trees, there shall be at least 85% absolute cover over the restored area and at least 75% survival of planted trees by the end of the five-year plant monitoring period. For wetland restoration and establishment areas, at least 75% absolute vegetative cover must be achieved, and the number of dominant species must be greater than 51% absolute cover of faculative wetland indicator status plant species at the end of Year 5. At the end of Year 5 in either the riparian tree planting or wetland planting areas, if these success criteria are not met at the mitigation sites there will be replanted with live plantings and an additional three years of monitoring to achieve the success criteria.

3.1.2 Surface Area of Wetland and Riparian Tree Mitigation The surface area of of riparian tree cover will be at least 3.3 acres and the surface area of wetlands will be at least 1.6 acres for the combined area of both onsite and offsite mitigation sites for each respective habitat type. The onsite mitigation will total 1.1 acre of riparian trees and 0.95 acre of wetlands. The 0.95 acre of onsite wetlands will be achieved through restoring 0.29 acre of wetlands in areas of temporary wetland impacts and re-establishing 0.36 acre of wetlands adjacent to areas of permanent wetland impacts. The additional offsite mitigation

Estero Americano Creek Bridge Replacement Habitat Mitigation and Monitoring Plan 20

will revegetate 2.2 acres of riparian trees and restore or establish 0.95 acre of wetlands at locations to be determined at the Estero Americano Coastal Preserve. The minimum habitat surface areas will be confirmed by Caltrans and/or its designee through monitoring to ensure as-built plans with these areas are completed and meet other success criteria. The habitat area will be documented with photographs and GIS for inclusion in the final report, if needed.

3.1.3 Soil Stability The restored and established wetland and riparian areas will be qualitatively examined for signs of substantial erosion formation of rills or bank slumps by Caltrans and/or its designee during annual vegetation monitoring visits. The location of substantial erosion will be documented with photographs and GPS for inclusion in the annual report and maintenance actions requested, if needed.

Erosion of soils along the banks of the unlined riparian tree and wetland areas would result in increased sedimentation and hydromodification and reduced water percolation and filtering via vegetation and soil, thereby decreasing the functional value of these habitats. Therefore, the riparian tree plantings, pocket wetlands, wetlands ditches, and other wetland areas shall be maintained to ensure they provide the target habitat functions of surface water quality enhancement and detention.

3.1.4 Hydric Soil Indicators The development of USDA NRCS hydric soil characteristics appropriate for the region (e.g. as determined by Corps Regional Supplements to the Corps Delineation Manual) in restored and/or established wetlands will be confirmed by Caltrans and/or its designee before the end of the monitoring period. Wetlands delineation at the project site was performed in 2013, and the USDA NRCS hydric soil characteristics of wetlands identified at that time and appropriate for future studies include, but are not limited to, chroma, depleted matrix, redox dark surface, redox depressions, and red parent material. A wetland delineation will be performed in mitigation wetlands in Year 5 to verify all success criteria are met. If the final success criterion for hydric soil indicators appropriate for the region in Year 5 has not been met, remedial actions would be implemented and monitoring continued until the criterion has been achieved.

3.2 Monitoring and Reporting

Caltrans and/or its designee will conduct maintenance and monitoring activities quarterly for the three year plant establishment period and annually for two years thereafter, for a total minumum monitoring period of five years. Routine qualitative monitoring will be conducted

Estero Americano Creek Bridge Replacement Habitat Mitigation and Monitoring Plan 21

quarterly using a monitoring checklist, which will be generated based on permit conditions and success criteria, detailed in Section 3.1. Qualitative monitoring methods will include evaluating plant health and vigor, watering, and identfying and addressing plant mortality. Additionally, vegetative percent cover by plant species will be monitored in riparian tree and wetland areas. The installation contractor will determine the watering schedule and maintain the survivorship per the plant establishment for the first three years.

Sampling will include visual estimates of tree survivorship and vegetative perecent cover by species. Survivorship will be relative to the as-built quantities for each tree species.

Photo-documentation of the unlined ditches and temporarily impacted wetlands will be conducted annually for 5 years from the locations marked during preparation of the as-built plans. Additional photographs will also be taken to record any events that may have a significant effect on the success of revegetation such as flood, fire, or vandalism. Photo points will be established to document re-vegetation efforts. The photo-documentation will be conducted yearly for five years and submitted to the agencies with the annual monitoring report.

An annual monitoring report shall be submitted to CDFW, CCC, ACOE and NCRWQCB by December 31 of each year beginning the year after the completion of each planting. Each report shall include:  A summary of each year’s results;  Recommendations of any remedial actions;  A summary of maintenance activities;  Photographs from the project site photo points, and  Monitoring data sheets.

The key dates for mitigation and monitoring activities at both the onsite and offsite projects are summarized in Table 3.1.

Table 3.1 Mitigation and Monitoring Schedule Action/Deliverable Date

Riparian tree cutting and willow harvesting Fall 2016

Begin bridge construction April 2017

Revegetation onsite Fall 2017 and Fall 2018

First monitoring survey (quarterly) of onsite Fall 2018

First monitoring report (annual) of onsite December 2018

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Final monitoring survey of onsite September 2023

Final monitoring report of onsite Decemeber 2023

3.3 Offsite Long-term and Adaptive Management Plan

A long-term and adaptive manangement plan will be drafted in coordination with TWC and Sonoma County to ensure that the mitigation work remains viable in perpetuity within the present and future management of the Estero Americano Coastal Preserve. This management plan will be incorporated into the final scope of work agreement with TWC and will be shared with agency partners for review prior to final approval.

3.4 Financial Assurances

Caltrans completed an estimate of the required mitigation for the project during early planning stages, and has allocated funds to pay for offsite mitigation. The preliminary estimate of costs per acre of offsite mitigation at the Estero Americano Coastal Preserve provided by TWC falls within the allocation of funds estimated by Caltrans. Additional financial assurance documentation can be provided by Caltrans to agency partners on request.

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Appendix A Figures

Estero Americano Creek Bridge Replacement Habitat Mitigation and Monitoring Plan 24

197

192 179 199

196 44 250

184

198 33

14 185 194

39 240

38 183 182 23

186 237

37 30

239

241

218

242

187 178

189 58

191 217

181 36

177

53 52

11 1 42

22 40

44 21

501

500

19 61

503 20 41

9 11

505 8

504 13

6 7

3 7

5 6

9 1

Project Location 19 20

18 2

64 34

1 3

36 37

38 7

4 3

6 1

50 10

2 47

31 1

Project Location

4 3

1 6

19 17

18 23

2 Service Layer Credits: Sources: Esri, 1

HERE, DeLorme, USGS, Intermap, 5 1 increment P Corp., NRCAN, Esri Japan, 6

1 2

METI, Esri China (Hong Kong), Esri 2

3 (Thailand), TomTom, MapmyIndia, © 1

22 24 OpenStreetMap contributors, and the 5

18 GIS User Community 2 3

1 6 16

10 15 13

523

2 30

31 1

27 25

FIGURE 1 - REGIONAL LOCATION Legend Estero Americano Creek Bridge Replacement SON-1-PM 0.0/0.1, MRN-1-PM 50.1/50.5, Project Location EA 04-20950, Project ID 04-1200-0116 Sonoma and Marin Counties County Boundary 0 5 10 20 Miles F VALLEY FORD TWO ROCK

Project Location

Service Layer Credits: Sources: Esri, HERE, DeLorme, TomTom, Intermap, increment P Corp., GEBCO, USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Ordnance Survey, Esri TOMALES POINT REYES NE Japan, METI, Esri China (Hong Kong), swisstopo, MapmyIndia, © OpenStreetMap contributors, and the GIS User Community

FIGURE 2 - PROJECT LOCATION Legend Estero Americano Creek Bridge Replacement Project Location SON-1-PM 0.0/0.1, MRN-1-PM 50.1/50.5, EA 04-20950, Project ID 04-1200-0116 County Boundary Sonoma and Marin Counties USGS Quads 0 0.75 1.5 3 Miles F Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community

Legend FIGURE 3 F PROJECT COMPONENTS Project Footprint 0 0.075 0.15 0.3 Bridge Estero Americano Creek Bridge Replacement State Route 1 Pavement SON-1-PM 0.0/0.1, MRN-1-PM 50.1/50.5, EA 04-20950, Project ID 04-1200-0116 Miles RetainingWalls Sonoma and Marin Counties Embankment Fill Slope 5 6 1 2

8 7

^ _ _

^ 4 ^ _

^ _

^ 3 ^ _

^ _

^ _ ^ _ ^ _

^ _

^ _ ^ _

^ _

^ _ ^ _

^ _

8 7 3 4

Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community

Legend FIGURE 4 F NATURAL REOURCES ^_ Oregon ash Wetlands WITHIN PROJECT FOOTPRINT 0 0.075 0.15 0.3 ^_ Klamath hawthorn Project Footprint Estero Americano Creek Bridge Replacement ^_ Mature Red Willows Bridge SON-1-PM 0.0/0.1, MRN-1-PM 50.1/50.5, ^_ Rare Plants State Route 1 Pavement EA 04-20950, Project ID 04-1200-0116 Miles Sonoma and Marin Counties Willow Thickets RetainingWalls U.S. Waters Embankment Fill Slope ESA Area: 0.2 acre of upland vegetation and rare plants

5 6 1 2 8 7 4 3

8 7 3 4 ESA Area: 0.1 acre of U.S. waters, riparian vegetation, and 13 mature willows

Service Layer Credits: Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community

Legend FIGURE 5

Project Impact Area Mixed willow thicket Bridge F PROJECT IMPACTS ^_ Oregon ash U.S. Waters Retaining Walls 0 0.075 0.15 0.3 ^_ Klamath hawthorn Wetlands Embankment Fill Slope Estero Americano Creek ^_ Mature Red Willows ESA Fence Bridge Replacement SON-1-PM 0.0/0.1, MRN-1-PM 50.1/50.5, ^_ Rare Plants Project Footprint EA 04-20950, Project ID 04-1200-0116 Miles Arroyo willow State Route 1 Pavement Sonoma and Marin Counties

Appendix B Project Site Photos

Estero Americano Creek Bridge Replacement Habitat Mitigation and Monitoring Plan 25

Appendix B Project Site Photographs

Estero Americano Bridge Replacement Project BSA – Looking Southeast, August 2013

East Side of Estero Americano Bridge, March 2014

Estero Americano Bridge Replacement Project, EA 209500 B-1 Appendix B Project Site Photographs

Project Area – Looking South, March 2014