9.10_-_Incidental_Harassment_Authorization_Application_7-22-16.pdf

Murray Street Bridge (# 36C-0108) Seismic Retrofit Project

Incidental Harassment Authorization Application

Murray Street Bridge

Santa Cruz Small Craft Harbor City of Santa Cruz

Santa Cruz County, CA Federal Project Number STPLX-5025 (048)

January 2015 Revised July 2016

For individuals with sensory disabilities, this document is 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: Brandy Rider, Senior Environmental Planner, 50 Higuera Street, San Luis Obispo, California 93401; (805) 549-3970 Voice, or use the California Relay Service TTY number, 1 (800) 735-2929.

Murray Street Bridge (# 36C-OI08) Seismic Retrofit Project

Incidental Harassment Authorization Application

Murray Street Bridge Santa Cruz Small Craft Harbor

City of Santa Cruz Santa Cruz County, CA

Federal Project Number STPLX-5025 (048)

USFWS: 81440-2010-1-0451

NMFS: ARN: 151422-SWR-2010-SR00471

January 2015 Revised June 2016

Approved By: --"'-(!"""'-tI-'~~A~+-t+-1"""'-"="" ~~c (~"~=...lr~;t\2""'::,,~_Date: {(hz;! bc~i sch~eiter, Assistant Director Phone Number: 831-420-5422 Office Name: Department of Public Works District/Region: City of Santa Cruz

Approved By: ---------- Date: _ Randy LaVack, Senior Environmental Planner Phone Number: 805-549-3182 Environmental Stewardship Branch Caltrans District 5

Murray Street Bridge Seismic Retrofit Project Incidental Harassment Authorization Application

Incidental Harassment Authorization Application

MURRAY STREET BRIDGE SEISMIC RETROFIT PROJECT (STPLX-5025 (048) )

CITY OF SANTA CRUZ, SANTA CRUZ COUNTY, CALIFORNIA

Table of Contents

1. Description of the Activity

Location and Setting Project Overview and Purpose Description of Activity Construction

2. Dates, Duration and Geographic Region

3. Species and Numbers of Marine Mammals

4. Affected Species and Distribution Survey Methods Distribution of Marine Mammals

5. Type of Incidental Take Authorization Requested

6. Take Estimates Marine Mammals

7. Anticipated Impact of the Activity Construction Impacts Species Impacts

8. Anticipated Impacts on Subsistence Uses

9. Anticipated Impacts on Habitat

10. Anticipated Effects of Habitat Impacts on Marine Mammals

11. Mitigation Measures

12. Arctic Plan of Cooperation

13. Monitoring and Reporting

14. Suggested Means of Coordination

15. References Personal Communications References Preparation

16. Glossary

List of Tables

1. Summary of Bridge Pile Type and Numbers

2. Marine Mammal Populations

3. Estimated Incidental Takes

ATTACHMENT A-FIGURES

FIGURE 1: Project Location

FIGURE 2: Area of Potential Impact

FIGURE 3: Bridge Cross Section

FIGURE 4: Distribution Of Observed Marine Mammals

FIGURE 5: Photographs of Hauled-Out Marine Mammals During Fall 2009 Surveys

FIGURE 6: 1,000 Meter Limit From Construction Area

ATTACHMENT B-Technical Tables

TABLE B-1: Murray Street Bridge Retrofit Project: Construction Phasing & Approximate Schedule

TABLE B-2: Numbers of Animals Hauled Out & Haul-Out Locations within Murray Street Bridge Surveys

TABLE B-4-A: Estimated Potential Harassment of Marine Mammals During Murray Street Bridge Seismic Retofit Construction Activities

TABLE B-4-B: Summary of Pile Driving

TABLE 5: Existing Noise Levels – Murray Bridge Area

TABLE 6: Noise Levels of Construction Equipment

ATTACHMENT C-Hydroacoustic Analysis

1. Description of the Activity

Location and Setting

The proposed project is located at the eastern edge of the City of Santa Cruz in the county of Santa Cruz (see Figure 1 in Attachment A). The project area includes the Murray Street Bridge which spans the Santa Cruz Small Craft Harbor, portions of lands within the Santa Cruz Port District harbor area, portions of the harbor waters, and the area along the Murray Street road right-of-way, west of Lake Avenue. See Figure 2 in Attachment A, which shows the harbor, docks and surrounding land uses. The GPS coordinates (from Caltrans Structure Inventory and Appraisal [SI&A] sheet) are:

� Latitude: N 36 degrees, 58 minutes 4 seconds

� Longitude: W 122 degrees, 00 minutes 10 seconds

Three marine mammals are known to occur within the Santa Cruz Small Craft Harbor: southern sea otter (Enhydra lutris nereis), harbor seal (Phoca vitulina richardii); and the California sea lion (Zalophus californianus). All marine mammals are protected under the Marine Mammal Protection Act. The docks and other features within the study area are haul-out sites for harbor seal and California sea lion. The open water of the study area provides habitat for the southern sea otter, the harbor seal, and the California sea lion.

Project Overview and Purpose

The proposed project consists of a seismic retrofit of the existing Murray Street Bridge, which spans the Santa Cruz Small Craft Harbor, and additional minor modifications to replace deficient bridge barriers (widening shoulders to standard widths and replacement and improvement of sidewalks and railings). The seismic retrofit project will provide the bridge with additional vertical support and resistance to lateral seismic forces by installing additional pilings and supplemental structural elements. In order to provide sufficient area for construction operations, some boats, Harbor facilities, and commercial businesses will require temporary relocation.

The nine-span bridge is supported by two abutments (identified as Abutments 1 and 10, located at the western and eastern ends of the bridge, respectively) and 8 “bents” (identified as Bents 2 through 9, located at 60-foot intervals between the abutments. Figure 3 provides a cross section showing the abutment and bents and proposed improvements. The seismic retrofit project consists of the following basic elements:

(1) Installation of concrete infill walls at Bents 2, 3, 4, and 9 to span the voids between the existing concrete support columns. The infill walls will also span the void between the existing and new columns at Bent 9.

(2) Installation of shear keys and seat extenders at Abutments 1 and 10 and Bents 2 through 9.

(3) Retrofit of foundations with 16-inch diameter CISS (cast-in-steel-shell) piles at Bent 9 and Abutments 1 and 10. These piles will extend to depths of approximately –100 feet at Bent 9 and to depths of approximately –40 feet to –55 feet at Abutment 10.

(4) Retrofit abutment with two 96-inch CIDH piles (cast-in-drilled-hole) piles behind Abutment 10 to a depth of -55 feet.

(5) Retrofit of both outriggers and bents with 30-inch diameter CISS piles at Bents 5, 6, 7, and 8 and 30-inch diameter CIDH piles at Bents 2, 3, and 4. These piles will extend to depths of approximately -55 feet to -85 feet at Bent 5 and at approximately –100 feet to –120 feet at Bents 6-8.

(6) Installation of fenders to protect boats passing by the pier foundations, new pile caps at Bents, 5, 6, 7, and 8, and replacement of existing fender.

(7) Installation of new retaining walls.

The bridge seismic retrofit will include removal and installation of piles as summarized on Table 1, including on land piles for the bridge structure and associated retaining walls. As shown, eight additional on land piles may be added to support relocation of a sewer line. In addition, 35 14-inch concrete piles would be removed at Docks FF and T to accommodate project construction with reinstallation upon completion of construction. Additionally, a temporary trestle to facilitate installation of the permanent bridge piles is being evaluated for installation. The construction of temporary trestle is estimated to include a maximum of 120 12-inch steel piles and would be removed upon completion of construction.

Description of Activity Construction

In-water and on-land construction activities that result in noise and vibration may result in incidental take (harassment) of marine mammals present in the area at the time of construction.

Construction will occur within harbor waters and on lands adjacent to the harbor. The construction phasing and approximate schedule is presented on Table B-1 in Attachment B.

In-Water Construction Activities. The construction schedule includes 10 months of potential in-water construction activity over 2 years – 5 months during the first year and 5 months during the second year. Activities include: removal of adjacent docks to accommodate construction access;

potential installation of piles for a temporary construction trestle from the bridge; pile driving;

transport of materials; and replacement of harbor docks upon completion of the bridge seismic retrofit project. In-water activities would be intermittent throughout the 5-month periods, but it is conservatively assumed that some activity could occur daily throughout these periods.

§ Installation of Bridge Piles: The most intense activity would be the installation of new bridge support piles, which will also involve the demolition of the existing piles at Bent 6. Two CIDH 30-inch piles will be installed at Bent 4. CISS piles at Bents 5 through 8 will be installed within the waterway by driving 30-inch steel casings either to refusal at rock or into a shaft drilled within rock (depending on the location). The installation of new piles at Bents 5 through 8 will include two piles on each side for a total of 16 piles in the water (and 10 additional piles at Bents 4 and 9 that are partially in the water). The work activity will be focused within the area of the bridge. Overall the installation of piles is expected to take a total of approximately 1.5 days for each 30-inch pile and 0.5 days for each of the eight16-inch piles at Bent 9 for a total of 48.5 days. The installation of these piles requires the use of a crane(s), a drilling rig, a pile driver, excavation and earthmoving equipment, concrete trucks and pumps, concrete vibrators, supply trucks, welding equipment, and other machinery. Based on the geotechnical site characteristics, permanent bridge piles will be partially or entirely vibrated into the Harbor substrate rather than driving them entirely by means of “hammering”. A vibratory hammer would be used to start driving all sheet piles, but an impact hammer may be required to complete driving depending on the density of subsurface materials.

Table 1. Summary of Bridge Pile Types and Numbers Location Number Pile Type

In Water § Removal-Bridge Bridge Bent 6 4 14-inch P/C Concrete § Remove Dock FF & T Piles Dock FF & T 35 14-inch P/C Concrete

Total In Water Removal 39 § Install New Permanent Bridge Bent 4 2 30-inch CIDH*

Bridge Piles Bridge Bent 5 4 30-inch CISS Bridge Bent 6 4 30-inch CISS Bent 7 4 30-inch CISS Bent 8 4 30-inch CISS Bent 9 8 16-inch CISS

Bridge Subtotal 26 § Install New Dock FF & T Piles 35 14-inch P/C Concrete

Total In Water Bridge Pile Installation 61 On Land § Install New Permanent Abutment 1 4 16-inch CISS

Bridge Piles Bridge Bent 2 2 30-inch CIDH* Bridge Bent 3 2 30-inch CIDH* Abutment 10 6 16-inch CISS Anchor Piles 2 96-inch CIDH

Bridge Subtotal 16 § Install New Retaining Wall Piles Retaining Wall 11

Retaining Wall 17 Retaining Wall 18

24-inch CISS 24-inch CISS 24-inch CISS

Total On Land Pile Installation 103 Optional In Water § Install and Remove Trestle

Install Temporary Piles Adjacent to Bridge 120 12-inch steel pipe piles Remove Temporary Piles Adjacent to Bridge 120 12-inch steel pipe piles

Total Optional In Water Pile Installation 240 Optional On land Piles** § Install New Permanent Bridge

Piles

Abutment 1

Bent 3 Abutment 10

16-inch CISS 30-inch CIDH 16-inch CISS

Total Optional On Land Pile Installation 8

* Permanent casing will be driven or vibrated into place.

** To support a relocation of a sewer line that is under consideration.

§ Installation of In-Water Barge or Temporary Bridge Trestle: Installation of an in-water barge or temporary bridge trestle is planned to accommodate equipment for pile installation. Work within the waterway will require either the use of barges or the construction of temporary trestles to provide work platforms. If barges are utilized, prefabricated modular units may be brought to the site and locked together. This type of platform can be installed, reconfigured, and removed relatively quickly, but the system is not suitable for areas that are too narrow to accommodate the modules. For example, footings from the Union Pacific Railroad Bridge to the north and footings from the Murray Street Bridge appear too close together to allow use of a modular barge between footings. In these areas, a trestle likely will need to be constructed.

§ Removal and Replacement of Boat Berths: The temporary use of portions of the eastern harbor boat yard and the western parking lot for contractor staging, in combination with provision of construction access to the bridge from the waterway, will result in temporary disruptions of harbor activities including temporary removal of existing boat berths and replacement upon completion of the project. To accommodate construction staging and in-water construction, the project calls for the temporary relocation of berths at Dock FF and Dock BY (Boat Yard on east side) to existing visitor berths with reconstruction of Dock FF and Dock BY upon completion of the bridge seismic retrofit construction. Dock FF (see Figure 2) accommodates University of California Santa Cruz (UCSC) boats that are used for university classes. A walking dock (gangway) would be constructed to connect the existing parking lot area to the portion of Dock FF that will remain during construction. Six temporary berths may be constructed adjacent to the gangway to minimize relocation of some of the existing boats. Upon completion of construction, no additional new boat berths will be constructed as was originally proposed. Although design plans have not yet been completed for the reinstalled berths, it is expected that the berth docks would be plastic, wood or concrete over polyethylene floats and would be anchored with pilings. Piles would be driven into the harbor floor by mechanical hammer. There would be no dredging or placement of fill in harbor waters with reinstallation of docks and both berths.

On Land Construction Activities. The proposed project includes the other construction activities that are located on land as follows:

§ Demolition: Demolition activities include the removal of pilings at Bent 6, temporary removal of the gangway under Bent 4, the removal of existing sidewalks and railings along the entire length of the bridge, and the removal of pavement at both ends of the bridge.

Equipment for demolition activities includes cranes, excavators, front-end loaders, dump trucks, concrete saws, and jackhammers.

§ Pile and Anchor Installation Outside Waterway: The CISS piles at Abutment 1, Bent 9 and Abutment 10 will be installed by driving 16-inch steel casing to depths of approximately – 30 to –90 feet and filling them with concrete. The 96-inch diameter anchor pile for Abutment 10 will require excavation and installation of a temporary steel casing, which will be filled with concrete. The 30-inch CIDH piles at Bents 2-4 will be installed by first driving 30-inch steel casing to depths of approximately -70 to -90 feet and filling them with concrete. The anchor pile excavation will be dewatered by pumping, if necessary.

Additionally, eight piles may be installed (Abutments 1 and 10 and Bent 3) to support a relocation of a sewer line that is now under consideration. The installation of these piles will require the use of excavation equipment, soil tamper equipment, and the other construction equipment described above for installing piles within the waterway.

§ Bridge Construction: The project includes installation of new girders on the southern edge of the bridge, the installation of a cantilevered extension along the northern edge of the bridge, and the construction of barrier railings as well as the installation and construction of various project features below the bridge road surface and above the piles. Equipment required for this part of the project would include a crane, concrete trucks and pumps, supply trucks, welding equipment, and other machinery.

§ Retaining Walls: Four retaining walls are planned on the south side of the bridge with two each on the east side and the west side. A total of 87 on-land piles will be driven to support the retaining walls as summarized on Table 1. This total does not include 27 piles that will be drilled, not driven, for one retaining wall (9).

§ Roadway Approach Construction: Excavation of existing road approaches up to 200 feet from each end of the bridge will be performed. Gravel base and asphalt concrete will be placed to match the new widened bridge deck. Equipment used will be typical paving equipment including graders, loaders, bulldozers, rollers, dump trucks, and a paving machine. Metal beam guard railings will be placed at each corner of the bridge.

§ Construction of Temporary Trestle: Construction of a trestle could vary depending on materials available to contractors. One possible trestle configuration would be 60-foot long steel girders over the Harbor navigation channel. The spans would be supported on falsework bents, perhaps constructed of steel piles which are a fairly common falsework material. Piles would be driven in the water by a crane sitting over the land. Preliminary estimates by the project engineer indicate that up to 120 12-inch steel beams would be required for a trestle spanning the bridge; vibratory drivers would be used. Installation of these piles is expected to take approximately 0.5 days for each pile. All piles would be removed at the end of construction. The trestle could be made of “Bailey Bridge” panels that can be used to provide bents or towers. The deck might be made of heavy timbers or open-grid panels with a safety railing to keep people and materials on the deck.

§ Contractor Staging: Contractor staging activities for Phases 1 and 2 of the project will take place in an approximately 8,000 square-foot portion of an existing boat yard near the eastern edge of the bridge. Contractor staging activities for Phases 3, 4, and 5 of the project will take place in the northern portion (approximately 11,000 square feet) of a parking lot situated at the western edge of the bridge. This staging area will be used through the end of Stage 5, when original facilities will be restored.

§ Temporary Harbor Facility Relocation: The temporary use of portions of the eastern harbor boat yard and the western parking lot for contractor staging as described above, in combination with provision of construction access to the bridge from the waterway, will result in temporary removal, relocation and replacement of some Harbor facilities, including temporary relocation of boats in the on land boat yard on the east side of the

Harbor that will be temporarily relocated to boat storage for approximately four months.

On the west side, 60 rowing boats stored under the existing Murray Street bridge will be temporarily relocated to an on land dry boat storage facility near docks A and B, and an additional 200+ square feet of storage area will be constructed to accommodate the temporary row boat storage. Row boats stored under Span 2 and UCSC Rowing Facility boats under Span 1 will be temporarily relocated to the US Coast Guard parking lot and fenced.

Uses at existing offices, bathroom facilities, and storage areas located north of the western staging area (and within the City of Santa Cruz’s right-of-way) will be displaced during Phases 3, 4, and 5 of the project. The buildings will be protected during construction, and a temporary 600 square foot facility (modular) will be installed on the US Coast Guard parking area for a period of approximately six months, which will temporarily house these businesses.

2. Dates, Duration and Geographic Region

The Murray Street Bridge Retrofit project is currently planned to commence in the fall of 2017.

The project area includes waters within the Santa Cruz Small Craft Harbor and adjacent lands managed by the Santa Cruz Port District (see Figure 2). The study area consists of the open waters, docks, and other potential haul-out features of the Harbor from the Harbor Launch Ramp area (including the fuel dock and Vessel Assist dock) up to 500 feet upstream of the boundary of the Area of Impact (see Figure 2 in Attachment A).

The Murray Street Bridge Retrofit project is tentatively proposed for construction in five partially overlapping interchangeable phases. Generally, work will begin on the eastern side of the Harbor and progress to the western side. The timing of each phase and a brief description of work to be performed during each phase is provided in Table B-1 in Attachment B.

Overall, the seismic retrofit work will be executed over a period of approximately 18 months within four construction phases as described in Table B-1. The additional bridge improvements will be constructed over a period of approximately 6 months as part of Phase 5 of the construction.

In-water activity will occur in Phases 2 and 4 over an approximate total 10-month period over two years with 5 months during the first year and 5 months during the second year. However, the phases may overlap. Work tasks will vary throughout the phase. The in-water pile driving for the bridge piles would occur over a total of 48.5 days within this period.

Due to in‐water work timing restrictions to protect federally‐listed salmonids, all in‐water construction activities including pile removal/installation would occur between the period from July 1 to mid-November unless otherwise permitted by the National Marine Fisheries Service

(NMFS).

In summary, the project would result in removal of 4 existing bridge piles; installation of 42 permanent bridge piles (in-water and on land); removal and reinstallation of 35 boat berth piles;

and potential installation of 8 additional piles on land, as well as, installation and removal of 120 temporary piles to support a construction trestle. In total, up to 109 days of pile driving and 19.5 days of pile removal, are anticipated for the bridge and dock piles. This covers both in and out of water pile driving and removal. Installation and removal of a temporary construction trestle would require 60 days for installation of and 30 days for removal. The actual number of days required to install each pile will be dependent on the experience level of and equipment used by the contractor and the site conditions encountered at each location.

3. Species and Numbers of Marine Mammals

Three marine mammals are known to occur within the Santa Cruz Small Craft Harbor:

§ Southern sea otter (Enhydra lutris nereis), federally listed as threatened and listed by the California Department of Fish and Game as “Fully Protected”;

§ Harbor seal (Phoca vitulina richardsi); and

§ California sea lion (Zalophus californianus).

The open water of the study area provides habitat for the southern sea otter, the harbor seal, and the California sea lion. Southern sea otters appear to be incidental visitors to the Harbor, using the site for foraging. Harbor seals use the harbor for foraging and use Docks F and FF as haul-out areas. California sea lions use the harbor only occasionally for hauling out and are incidental visitors to the Harbor, using the waters for foraging and the docks and other features within the study area as occasional haul-out sites. California sea lions are present when fish runs occur within the harbor. (Weather, currents, seasonal upwelling conditions, and other oceanographic factors periodically bring anchovies, sardines, and other prey species into the Harbor, in turn drawing great numbers of birds and marine mammals.) Table 2 summarizes the status, local occurrence and total range/population for these species.

4. Affected Species and Distribution

Survey Methods

Nineteen marine mammal surveys were conducted between December 2006 and October 2009 by EcoSystems West Consulting Group. Numbers of each of three species (California sea lion, harbor seal, and southern sea otter) using the area surrounding the Murray Street Bridge (Bridge) were estimated. The type of use, especially during the period of time when in-water construction activities are proposed for the project, was determined. A total of 40 survey hours were conducted, including early morning, midday, evening and nighttime surveys with an emphasis on early morning and midday surveys. In an effort to determine the diurnal and nocturnal movement patterns of the harbor seals, initially 3-4 site visits/day were conducted, 2 times per week.

Table 2. Marine Mammal Populations Common

Name Scientific

Name Status [1] Occurrence in Santa Cruz Harbor Total Range and Population [1] Numbers Seasonality Range Abundance

California Sea Lion

Zalophus californianus Not Listed [2] 1-15

Occasional, especially when prey species are present

California to Canada 296,750

Harbor Seal (Eastern Pacific subspecies)

Phoca vitulina richardii Not Listed [2] 1-11

Summer, Fall, Winter-outside breeding seasons

Mexico to Alaska

30,968 in California

Southern Sea Otter

Enhydra lutris nereis Threatened 1-2

Incidental Visitor

California, Santa Barbara to San Mateo

County

2,865

[1] From “U.S. Pacific Marine Mammal Stock Assessments, 2015.” August 2014. U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Southwest Fisheries Science Center

[2] Not listed as “endangered” or “threatened” under the Endangered Species Act nor as :”depleted” under the Marine Mammal Protection Act.

Once a general understanding of the harbor seals’ use of the area was gained, the surveys were focused on estimating the number of individuals present in the study area in the morning (when pile driving or other in-water activities might be expected to begin for the day) and around midday (when pile driving and other in-water activities might resume after a lunch break). An effort was made to determine the maximum number of individuals using haul-outs within the study area by arriving pre-dawn, when animals were still at rest and had not been flushed into the water by Harbor activities.

For each survey, the following were recorded: the time of the survey, the temperature, visibility, wind speed, tide, and moon phase. During surveys, one or two biologists walked and sat at key observations points, or rowed a small boat, throughout the study area, using binoculars to examine the site for presence of marine mammals. A general census of the area was taken on each site visit, counting the numbers of each species present, noting the activity of the animals, as well as their location, with reference to an aerial map of the Area of Influence and vicinity. Notations were made on the aerial map of the site, when necessary, to clarify locations of observed animals.

When feasible, observed animals were photographed, and the sex of California sea lions was noted.

It was not possible to determine with certainty whether or not an individual had already been counted (unless all animals remain hauled-out for the duration of the survey); however, an effort was made to avoid duplicating counts by taking into account the time and location of the observation with reference to previous observations. Where we were unable to determine if counts were redundant, we noted this on data tables.

Ecosystems West biologists also made note of fish activity, when they observed evidence such as jumping fish or congregations of feeding birds and mammals. EcoSystems West biologists also noted relevant personal communications with Port District employees, Harbor business employees, and marine mammal experts regarding marine mammal presence. Further, EcoSystems West biologists noted incidental observations of other wildlife species, such as bats or bird species, and recorded all observations on a standard data sheet designed for the Project’s marine mammal surveys.

Distribution of Marine Mammals

Table B-2 presents the estimates of marine mammals present in the survey area during 2009 surveys. Table B-3 presents the number of animals observed hauled-out and the haul-out locations during 2009 surveys. Figure 4 shows the spatial distribution of observed marine mammals throughout the survey area. Figure 2 provides an aerial view of the study area and shows the location of the docks referenced on the x-axis of the spatial distribution figure.

Figure 5 shows photographs of mammals observed during the surveys.

California Sea Lion. During the December 2006 surveys, one California sea lion was observed swimming under the western section of the Murray Street Bridge. During the September/October 2009 surveys, California sea lions were observed foraging and hauling-out within the Harbor on 18 of 19 survey visits (the exception was a nighttime survey where visibility was limited). The numbers of California sea lions observed varied widely throughout the survey period, from 1 animal to 13-15 animals/survey. The larger numbers of animals were observed when “rafts” of sea lions were present foraging throughout the survey area and fish presence was evident (September 30 –October 2).

California sea lions use the harbor only occasionally for hauling out and the specific haul-out location varied during initial site visits, throughout the marine mammal survey period, as well as during prior and subsequent incidental observations of the harbor. The closest regular haul-out location for large numbers of California sea lions is at the Municipal Wharf. Individuals and occasionally pairs of sea lions were observed hauled-out on docks throughout the survey area, on the fuel dock, and more commonly, on the Vessel Assist dock, and the docks on the western side of the Harbor, from AA to FF (see Table B-3). See Figure 3 for dock locations. One individual was observed hauled-out on the rubber Kayak docks under the Bridge. Figure 2 provides an aerial view of the survey area, with docks and other haul-out features identified. Some of the animals that were observed hauled-out appeared to be lethargic, remaining on the same or proximate dock for two or more days in a row, sometimes with a cough, or swimming without vigor in the adjacent waters. One juvenile was observed hauled-out on the cement wall on the western border of the Harbor between E and F Docks (see Figure 5). Observations of sea lions were distributed throughout the Survey Area, with a spike of observations in the area near the launch ramp, fuel dock, and Vessel Assist dock (see Figure 4).

California sea lions appear to be incidental visitors to the Harbor, appearing in the greatest numbers when schools of fish are abundant within the Harbor, as evidenced by jumping fish and large congregations of feeding birds and “rafts” of sea lions. Sick and weakened sea lions also appear to use the Harbor as a haul-out refuge. Young of the year sea lions faced an 85% mortality in 2009 due to starvation. This is likely caused by an El Nino-like response in prey resources (G.

Oliver, personal communication, 2009). While juvenile rock fish were abundant, anchovies were essentially absent, and while sardines were abundant, juvenile sardines were scarce (G. Oliver, personal communication, 2009; K. Carney, personal communication, 2009). Rock fish and adult sardines provide an adequate prey base for healthy adult sea lions, but may be too fast for juveniles or weakened adults to catch. In addition, more varied and scarce prey resources may require greater traveling distances and deeper diving for successful hunting, placing too great a metabolic demand on young of the year or weakened sea lions (M. Weise, personal communication, 2009; G. Oliver, personal communication, 2009). Spring and fall algal blooms causing damoic acid poisoning in sea lions may have also been a factor in the presence of hauled-out sea lions in the Harbor (N. Crane, personal communication, 2009). Similar influences will affect the presence of sea lions in the Harbor in subsequent years, but numbers will likely vary.

The Harbor does not provide mating or breeding habitat or other habitat of a similar ecological significance for the California sea lion.

Harbor Seal. During December 2006 surveys, six harbor seals were observed hauled-out on dock FF at night. During Fall 2009 surveys, harbor seals were observed foraging and telescoping on 18 out of 19 surveys. Numbers of observed harbor seals varied widely from 1 to 11 animals. Harbor Seals were only observed hauled-out on F and FF Docks, only during early morning surveys, and when biologists arrived prior to the onset of nearby early morning Harbor activities, such as the arrival of kayakers at FF Dock and “Velocity” Crew at F Dock. (Velocity is a private sports fishing and whale watching charter boat.) With any proximate activity, such as boat and human activities occurring in the harbor area, harbor seals may be flushed from their haul-out locations into the water.

Observations of harbor seals were concentrated in two locations: to a lesser degree in the area around the launch ramp, fuel dock and Vessel Assist dock; and primarily in the area around Docks F and FF and Dock S, the Live Bait dock, where harbor seals were frequently observed telescoping just off Dock S. The Live Bait dock clerk, Kevin Carney, and well as Port District staff report that five or six of the harbor seals appear to be residential, hauling-out, foraging, and telescoping in the area of Docks FF through S throughout the year (K. Carney, personal communication, 2009; B. Foss, personal communication, 2009).

The entire Upper Harbor, upstream (north) of the Bridge was surveyed once. This survey was conducted in an effort to assess potential use of the Upper Harbor during midday. Six harbor seals were observed foraging in the Upper Harbor.

Harbor seals are residential within the Harbor, using Docks F and FF as a primary haul-out and the surrounding area as foraging habitat. The Harbor does not provide breeding or molting habitat. Nearby known breeding and molting locations include Point Lobos, Elkhorn Slough (NOAA 2007), and Lover’s Point State Marine Reserve (SIMON 2008, which are approximately 20+ miles south of the Santa Cruz Small Craft Harbor. The harbor seals are not present on the beaches adjacent to the Harbor. The numbers of harbor seals occupying the Harbor are likely to be highest during late summer, fall and winter, outside of breeding (March - May) and molting (June - July) seasons. Nineteen visits were conducted within two periods: one in December and a second survey two years later in September and October. Thus, the estimates reflect maximum numbers as the surveys were conducted during all of these periods. Individuals that are not sexually reproductive may remain at the Harbor later into the spring, until molting season.

The harbor seals only use Docks F and FF as haul-out sites at night, when disturbances in the Harbor are at a minimum. The animals flush with any disturbance in the early morning. The total number of hours of haul-out time/day for harbor seals outside of breeding and molting season averages seven hours. It is unknown if the harbor seals occupying the Harbor use the site exclusively as their haul-out during the fall and winter or if they use other nearby haul-outs in conjunction with the Harbor. Use of multiple haul-out sites by harbor seals varies, as does distance travelled between multiple haul-out sites and for foraging.

In one study in Humboldt and Del Norte Counties, approximately half of the harbor seals tagged used one to two haul-out sites, and half used three or more, traveling an average distance of 28 km between sites. Males travelled further and sub-adult females travelled slightly further than sexually reproductive females (Pecharich, A.G. and P.D. Goley 2003). In a monitoring study of harbor seals for the Richmond San Rafael Bridge, 65% used more than one haul-out site, and when seals used Castle Rock as their primary haul-out, mean in-water distances from the haul-out site for most seals ≤ 5 km (i.e. foraging areas were located close to the primary haul-out site) (Green, D. et al. 2006).

In an unpublished study of harbor seal prey base, harbor seals using the San Lorenzo River in Santa Cruz were found to use the river as their haul-out exclusively, foraging in the ocean and returning during the night when disturbances were at a minimum (Weise, M. personal communication, 2009). Nearby known haul-outs for the eastern Pacific harbor seal include Pleasure Point in Live Oak; the Cement Boat at Seacliff State Beach in Aptos; Table Rock, off Wilder State Park; as well as numerous other sites along the north coast from Wilder State Park to Ano Nuevo State Park (NOAA 2007).

Southern Sea Otter. The southern sea otter is regularly sighted in the Harbor waters. During the December 2006 field surveys, one sea otter was observed swimming in the open water of the main Harbor channel, north (upstream) of the Murray Street bridge. During September/October 2009 surveys, southern sea otters were observed foraging in the Harbor during five of the nineteen surveys conducted, with observations concentrated during one week of the four-week-long survey period, between September 17 and 23 (Table B-2) . On four of these visits, only one sea otter was observed. On one visit, a mother and juvenile were observed and heard calling and responding until the pair reunited.

Southern sea otters appear to be incidental visitors to the Harbor. Otters occur in the kelp forests just off the coast, where separate groupings of females and young, territorial males, and non-territorial males breed, forage, and groom, in close proximity to the Harbor. Availability of food resources based both on seasonal variation and seasonal and El Nino-influenced ocean currents, as well as Spring and Fall algal blooms of a diatomic species of Pseudo-nitzschia, causing damoic acid poisoning may have been factors influencing the presence of otters in the Harbor during Fall 2009 surveys. Similar factors are likely to exist in subsequent years, but numbers will likely vary.

The Harbor does not provide mating or breeding habitat or other habitat of a similar ecological significance for the southern sea otter.

5. Type of Incidental Take Authorization Requested

The incidental harassment authorization request is for Level B incidental take (behavioral harassment) of the marine mammals (California sea lions, harbor seals, and southern sea otters) for incidental harassment of any marine mammal that might enter the 120 dB Zone of Influence (ZOI) during active pile driving activity. Noise, vibrations, and other physical disturbances can harass marine mammals. The range of effects potentially includes behavioral changes, physiological stress, physical injury (including hearing loss), and mortality.

The method of take is incidental harassment from disturbance associated with construction activities, personnel and equipment, and noise, deterring regular foraging and haul-out activities as well as from temporary removal of primary haul-out sites (Dock FF) for harbors seals. In addition, animals present in the Upper Harbor may be temporarily restricted (until the end of daily construction activities) from moving through the Work Area under the bridge to access the Harbor exit and other areas for foraging or hauling out.

Construction activities that may impact marine mammals primarily include pile removal (concrete and steel), augering, and pile installation (concrete dock pile, steel trestle pile and steel bridge pile). Other construction activities and noise sources include trucks delivering materials and other construction on land construction activities on the bridge, abutments and roadway.

The construction activities will be limited to the area around the bridge. Both in-water and in-air noise is expected during the course of construction, and potential impacts are discussed below in subsection 7. In-water activities principally consist of pile driving.

All noise-generating construction activities will take place during daylight hours, and would begin each day after harbor seals have already flushed from their haulouts, and during which time harbor seals might normally be congregating and foraging around Dock S and throughout the harbor. California sea lions may be foraging throughout the Harbor, particularly if prey fish species are abundant, and southern sea otters might be occasional visitors, foraging or seeking refuge in the Harbor. California sea lions may also use the docks within the Harbor for day-time haul-outs and be flushed by in-air noise. Behavioral effects, as further described below in subsection 7, would be similar for all three noise-generating activities, with the main differences being the duration, frequency, and total hours associated with each activity (see Table B-4).

6. Take Estimates Marine Mammals

Incidental harassment of marine mammals during the Murray Street Bridge Retrofit Project may occur to all three marine mammal species (southern sea otter, California sea lion, and harbor seal) present in the Area of Impact and vicinity. Avoidance and minimization measures will be implemented to reduce the potential for harassment to the maximum extent possible, as detailed in the subsection 11 below.

Incidental take is estimated for each species by estimating the maximum number of marine mammal being present within a ZOI during active pile driving based on estimates of numbers of animals identified during the marine mammal surveys. Numbers of residential harbor seals are expected to be at a maximum during the season in which surveys were conducted (outside of breeding and molting seasons).

Pile driving (in-water and on land) estimates are based on the maximum number of days that pile driving could potentially occur for:

§ Removal of 4 existing bridge piles;

§ Installation of 42 permanent bridge piles (50 if a relocated sewer line is placed on the bridge);

§ Installation and removal of 120 temporary piles to support a construction trestle, if used;

§ Removal and re-installation of 35 boat berth piles; and § Installation of on land piles for retaining walls.

In total, up to 48.5 days of pile driving and 19.5 days of pile removal are anticipated for the bridge and dock piles. Installation and removal of a temporary construction trestle would require 60 days for installation of 120 piles and 30 days for removal. Installation of on land piles is estimate to occur over 55.5 days. Therefore, a total of 219 days is estimated for all pile installation and removal activities as shown on Table B-4 and summarized below.

Total Estimated Duration of In Water Pile Installation (including optional trestle) = 108.5 days

Total Estimated Duration of In Water Pile Removal (including optional trestle) = 49.5 days

Total Estimated Duration of On Land Pile Installation = 55.5 days Additional Estimated Duration of On Land Pile

Installation For Piles That May Be Added = 5.0 days days

TOTAL 218.5 days

For the exposure estimate, it is conservatively assumed that the highest count of sea lions, harbor seals, and sea otters observed will be foraging within the ZOI and be exposed multiple times during the Project. The calculation for marine mammal exposures is estimated by:

Exposure estimate = N * (“X” days of pile driving activity + “X” days of pile removal), where:

N = # of animals Exposure estimate = N animals * “X” days

Enumeration of the anticipated incidental takes is shown on Table 3 based on the estimated number of piles and days of pile installation/removal shown on Table B-4 in Attachment B. In addition, a one-time harassment is predicted for harbor seals when Dock FF is temporarily removed.

Therefore, Caltrans and the City of Santa Cruz is requesting authorization for Level B acoustical harassment of up to 438 southern sea otters, 3,285 California sea lions, and 2,409 harbor seals due to pile driving and project related activities. It is assumed that these number estimates include multiple harassments of the same individuals.

Table 3: Estimated Incidental Takes

Maximum # of Animals/Day Total Days Total Incidental Take

During Construction

Southern sea otter 2 219 438

California sea lion 15 219 3,285

Harbor seal 11 219 2,409

7. Anticipated Impact of the Activity

The waters and haul-out features within the Harbor do not provide rookery, mating, breeding, molting, or other habitat of a similar ecological significance for sea otters, California sea lions or harbor seals. However, construction activities may impact marine mammals using the Harbor for foraging and haul-out activities. Construction activities that may impact marine mammals include pile removal (concrete and steel), augering, and pile installation (concrete dock pile, steel trestle pile and steel bridge pile). These activities will be limited to the area around the bridge.

Both in-water and in-air noise is expected throughout the duration of construction, with the most noise generated during pile installation operations, as pile removal and installation radiates sound into the water, the substrate, as well as the air. Other noise events would include trucks delivering materials, bridge removal equipment, concrete pumps, etc., none of which should generate as much noise as pile installation.

Current NMFS practice regarding exposure of marine mammals to high-level underwater sounds is that cetaceans and pinnipeds exposed to impulsive sounds of at or above 180 and 190 dB (RMS1), respectively, have the potential to be injured (Level A harassment). NMFS considers the

1 RMS refers to the sound pressure level that is the average of the squared pressures over the time that comprise that portion of the waveform containing 90 percent of the sound energy for one pile driving impulse (ICF Jones and Stokes, July 2010).

potential for behavioral (Level B) harassment to occur when marine mammals are exposed to sounds below injury thresholds at or above the 160 dB (RMS) threshold for impulse sounds (e.g., impact pile-driving) and the 120 dB (RMS) threshold for continuous noise (e.g., vibratory pile-driving).

Currently, no data are available describing baseline levels of underwater sound in Santa Cruz Harbor waters. Normal ambient noise levels in the harbor include vessel motors, heavy vehicular traffic on the bridge, construction noise from the dry dock repair facility, commercial charters, kayakers, and significant water traffic, to which marine mammals in the harbor are habituated.

Underwater noise levels are estimated to fall between 100 dB and 140 dB based on review of underwater sound levels in other areas (ICF Jones and Stokes, 2010).

The existing noise environment in the project area is dominated by motor vehicle movement on Murray Street/Eaton Street, Lake Avenue, Seventh Avenue and other nearby arterial streets.

Trains utilizing the tracks adjacent to the site, the operation of commercial and private boats in the harbor, and operation of boat yards engaged in repair activities also contribute sporadic noise incidents. Ambient noise levels were monitored as part of the preparation of the CEQA (California Environmental Quality Act) environmental review documents at the Lake Avenue entrance to the Santa Cruz Harbor on Lake Avenue. Noise levels were measured and are reported using percentile noise descriptors: L90 (the background noise level exceeded 90 % of the time), L50 (the median noise level exceeded 50% of the time), L1 (the peak level exceeded 1% of the time), and Leq (the average energy-equivalent noise level). Monitored noise levels are shown in Table B-5.

Construction Impacts

Steel pile driving construction activities associated with the bridge seismic retrofit project could result in behavioral responses by marine mammals and rise to the level of harassment. However, construction-generated underwater noise would not rise to the level associated with injury based on the results of a hydroacoustic analysis prepared by ICF International for the City of Santa Cruz, which is included in Attachment C. The analysis calculated the distances to the 120 dB, 160 dB, 180 dB, and 190 dB-RMS contours for the largest of each type of pile to be driven, which correspond to the following thresholds:

§ 190 dB-RMS – Pinniped injury (Level A harassment)

§ 180 dB-RMS – Cetacean injury (Level A harassment)

§ 160 dB-RMS – Cetacean and Pinneped disturbance under impact pile driving (Level B harassment)

§ 120 dB-RMS – Cetacean and Pinneped disturbance under vibratory pile driving (Level B harassment)

Pile Driving Construction Impacts. The most intense in-water activity would be the installation of new bridge support piles. CISS (cast-in-steel-shell) piles at Bents 5 through 8 will be installed within the waterway by driving 30-inch diameter steel casing either to refusal at rock or into a shaft drilled within rock (depending on the location). The installation of new piles at Bents 5-8 will include two piles on each side for a total of 16 piles in the water (and 10 additional piles at Bents 4 and 9 that are partially in the water). Table B-4 summarizes the length of time estimated for installation of each pile. The installation of these piles requires the use of cranes, a drilling rig, a pile driver, exaction and earthmoving equipment, and other equipment.

The results of the hydroacoustic analysis are presented on Table 1 in ATTACHMENT C, and are summarized below. The calculations are based on source levels for similar piles driven for similar projects, based on information provided in Caltrans’ Technical Guidance for Assessment and Mitigation of the Hydroacoustic Effects of Pile Driving on Fish (Caltrans, 2015)2. In accordance with NMFS guidance2, an attenuation rate of 4.5 dB per doubling of distance was assumed. The results of the analysis indicate the following:

1. The distance, within which the pinniped injury threshold of 190 dB-RMS is predicted to be exceeded, is 37 meters or less.

2. The distance, within which the cetacean injury threshold of 180 dB-RMS is predicted to be exceeded, is less than 170 meters.

3. The distance, within which the impact driving disturbance threshold of 160 dB-RMS is predicted to be exceeded, is 3,663…