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DRAFT COYOTE POINT RECREATION AREA CONCEPTUAL DESIGN REPORT

Prepared for County of San Mateo Parks and Recreation Department

Prepared by Philip Williams & Associates, Ltd. HJW Geospatial Treadwell & Rollo

April 2008

PWA REF. #1876.00

Services provided pursuant to this Agreement are intended solely for the use and benefit of the County of San Mateo. No other person or entity shall be entitled to rely on the services, opinions, recommendations, plans or specifications provided pursuant to this agreement without the express written consent of Philip Williams & Associates, Ltd., 550 Kearny Street, 9th Floor, San Francisco, CA 94108.

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TABLE OF CONTENTS

Page No. 1. 2. INTRODUCTION EXISTING SITE CONDITIONS 2.1 GENERAL PLAN OF SITE 2.2 GEOMORPHOLOGY 2.2.1 Geology and Geotechnics 2.2.2 19th and 20th Century History 2.3 BATHYMETRY 2.4 TOPOGRAPHY 2.4.1 Beach 2.4.2 Structures and Promenade 2.4.3 Recreational Area 2.5 TIDAL WATER LEVELS 2.6 100-YEAR COASTAL FLOODPLAIN 2.7 FUTURE RELATIVE SEA-LEVEL RISE 2.8 WIND-WAVES 2.9 TIDAL CURRENTS 2.10 SEDIMENT SUPPLY AND TRANSPORT DESIGN CRITERIA 3.1 SHORELINE PLANFORM 3.1.1 Crenulate Shaped Bays 3.1.2 Parabolic Bay Shape Equation 3.1.3 Direction of Wave Approach and Reference Angle of Wave Obliquity 3.1.4 Control Line Length 3.2 SHORELINE CROSS-SECTIONAL PROFILE 3.2.1 Backshore Berm Elevation and Width 3.2.2 Foreshore Slope FORMULATION AND EVALUATION OF ALTERNATIVES 4.1 ALTERNATIVES 4.1.1 Alternative 1: No Action 4.1.2 Alternative 2: Maintain Shoreline Armoring in its Current Position 4.1.3 Alternative 3: Crenulate Shaped Bay Between the Bay Trail and Coyote Point Headland 4.1.4 Alternative 4: Crenulate Shaped Bay Between the Bay Trail and the Retail Outlet 1 2 2 2 2 3 4 4 5 6 6 7 7 7 8 8 9 10 10 10 11 11 12 12 12 13 14 14 14 14 15 15

3.

4.

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4.1.5 4.1.6 4.1.7 5.

Alternative 5: Crenulate Shaped Nay Netween the Retail Outlet and Coyote Point Headland Alternative 6: Crenulate Shaped Bays Either Side of the Retail Outlet Options

16 17 17 18 18 19 19 19 20 20 21 21 22 22 23 25 26

PREFERRED ALTERNATIVE 5.1 OPTIONS WITH A CRENULATE SHAPED BAY WEST OF THE RETAIL OUTLET 5.1.1 Option to Create a Pocket Beach (Option 4a) 5.2 OPTIONS WITH A CRENULATE SHAPED BAY EAST OF THE RETAIL OUTLET 5.2.1 Option to Shift Crenulate Shaped Bay to the West (Option 5a) 5.2.2 Option to Shift Crenulate Shaped Bay to Seaward (Option 5b) 5.2.3 Cost Estimates for Alternative 5 and Options 5a and 5b 5.3 PREFERRED ALTERNATIVE 5.3.1 Alternative 5 to the East of the Retail Outlet 5.3.2 Alternative 5 to the West of Retail Outlet 5.4 PROVISIONAL PERMITTING DISCUSSIONS WITH BCDC REFERENCES LIST OF PREPARERS FIGURES

6. 7. 8.

LIST OF APPENDICES Appendix A. Geotechnical Report Appendix B. Beach Transects Appendix C. Detailed Cost Estimates

LIST OF TABLES Table 3-1. Table 3-2. Table 3-3. Table 5-1. Elevations of Key Structures Beach Dimensions NOAA Tidal Datums (1983-2001 epoch) for San Mateo Bridge (west side) Tide Gauge Opinions of Probable Costs of Construction for Alternative 5, Option 5a, and Option 5b

LIST OF FIGURES Figure 1. Figure 2. Site Location Map Coastal Frontage

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Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. Figure 8. Figure 9. Figure 10. Figure 11. Figure 12. Figure 13. Figure 14. Figure 15. Figure 16. Figure 17. Figure 18. Figure 19. Figure 20. Figure 21. Figure 22. Figure 23.

Site Photographs 1853 T-sheet of Coyote Point Coyote Point Beach in the 1880s Coyote Point in the 1920s Topographic Map Location of Transects Frequency of Offshore Winds Fetch Lengths to Coyote Point Crenulate Shaped Bay Theory and the Parabolic Bay Shape Equation Examples of Crenulate Shaped Bays in California Frequency of Nearshore Wave Energies Wave Runup Schematic Cross-Shore Section Conceptual Alternative 2 Coyote Point Marina Breakwater Conceptual Alternative 3 Conceptual Alternative 4 Conceptual Alternative 5 Option 4a Option 5a Option 5b

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1. INTRODUCTION

Coyote Point is a regional recreation area operated by the San Mateo County Parks and Recreation Department (County). The recreation area is located southeast of San Francisco International Airport (Figure 1) and its coastal section is a popular destination for swimmers, windsurfers, kayakers, cyclists, and walkers. In the 1990s a series of coastal structures were constructed along the frontage to provide erosion protection to the Recreation Area, and in particular to protect a pedestrian promenade adjacent to the beach. Presently, these structures are failing, leading to undercutting and damage to the seaward side of the promenade. The purpose of this project is to develop a sustainable solution to the coastal erosion problem while maintaining park functions. Part of the enhancement is to facilitate good public access to the beach and water for a variety of users, particularly swimmers and windsurfers. The project is divided into three phases, as follows: Phase 1 ­ conceptual alternatives and selection of preferred alternative Phase 2 ­ preliminary design, permitting and final design Phase 3 ­ construction period This document reports the findings of Phase 1; provision of a conceptual design for the restoration of the Coyote Point Recreation Area shoreline, to mitigate the potential for future erosion and storm damages. The Phase 1 project objectives are: recommend a conceptual shoreline design that maintains the Coyote Point Recreation Area promenade. extend the sustainability of the site through consideration of a stable shoreline configuration, which should be consistent with potential future implementation of beach nourishment. develop a conceptual design that provides good public access to the beach for swimmers and windsurfers. provide the conceptual design to a level that will be sufficient to accomplish a more detailed design and pursue funding to initiate environmental review/permitting as part of Phase 2 of the project.

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2. EXISTING SITE CONDITIONS

2.1

GENERAL PLAN OF SITE

The slightly concave north-facing coastal frontage of Coyote Point Recreation Area is approximately 2,000 ft long between a rock headland (up to 75 ft high) to the east (Coyote Point or historically Point San Mateo) and the point where the Bay Trail meets the coast to the west (Figures 1 and 2). A 12-ft wide promenade runs parallel to this frontage (immediately inland of the beach, Figure 2), which has been protected from coastal erosion by a variety of structures since the 1990s. These structures have recently fallen into disrepair through storm-wave damage, causing parts of the promenade to collapse. The damaged structures are fronted by a sand/gravel beach and backed by a low-lying land-filled area forming the northern part of the Recreation Area. The eastern section of the shoreline, an area popular with swimmers and sunbathers, is unprotected and erosion of the beach has exposed the soil/fill beneath the promenade to storm-wave attack. Erosion of the soil/fill has created a small cliff over which the promenade curb has collapsed (Figure 3). The central portion of the shoreline is protected by riprap, installed in 1991, which is in disrepair for some of its length (Figure 3). The riprap is replaced by an Armor Flex articulated block mat along the west section, which was installed in the 1990s to allow easier access to this part of the beach for windsurfers. The Armor Flex has been undermined by waves, which has caused slumping of the fabric and the structure to collapse under its own weight, steepening the Armor Flex surface slope (Figure 3). The northern portion of the Recreation Area itself comprises a mix of open grassland with bisecting walkways, east and west car parking lots, playgrounds, picnic areas and tree-shaded areas (Figure 2). Buildings close to the shoreline include restrooms at the eastern extremity of the site, a kite and windsurfing retail outlet located in the center of the coastal section, and an animal rescue center at the western extremity of the site. 2.2 2.2.1 GEOMORPHOLOGY Geology and Geotechnics

The region is underlain by rocks of the Franciscan Formation, comprising sandstones and shales (Graymer et al., 2006). Point San Mateo (Coyote Point) is an erosional remnant composed of resistant rocks (Figure 3) surrounded by softer rocks eroded to lower elevations. Based on a series of borehole logs (Appendix A) the near-surface geology of the Recreation Area comprises alluvial fan and fluvial deposits, overlain by marine clay (Bay Mud) overlain by fill. The Franciscan Formation was not reached, but is likely to be shallow at the eastern end of the site, towards the Coyote Point headland. The alluvial fan and fluvial deposits comprise medium stiff to hard clay,

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sandy clay, and clay with lenses of medium dense sand, gravel, and clayey sand. The overlying Bay Mud is approximately 2.5 to nine ft thick and consists of soft to stiff, highly plastic marine clay. The fill material is composed of stiff clay between approximately five and eight ft thick. An interpreted geological section along the promenade is presented in Appendix A. Groundwater was encountered at or just above the top surface of the Bay Mud. The groundwater level probably fluctuates with the tides, but does not drop below the Bay Mud because this unit is impervious. 2.2.2 19th and 20th Century History

In the mid to late 19th century the site of Coyote Point Recreation Area formed the northern extreme of an extensive area of salt marsh stretching south along the western shore of south San Francisco Bay (Figure 4). Point San Mateo formed an `island' surrounded by Bay waters on its north and east sides, and backed by this salt marsh on its west and south sides. Between the hinterland to the west and Point San Mateo, the salt marsh was approximately 2,000 ft wide. The salt marsh was likely a marsh plain at elevations near mean higher high water. The northern edge of the salt marsh was fronted by a beach, the antecedent of the present beach, and possibly some low dunes between the beach and the marsh. A photograph from the 1880s suggests that the beach was wide, sandy and suitable for bathers at this time (Figure 5). Sinuous tidal creeks cut across the marsh draining to the south from heads close to the beach (Figure 4). No creeks drained in a northerly direction. The creeks widened to the south, and the creek immediately to the south of Point San Mateo was navigable for small boats to reach a small wharf on its southeast side. During the 1890s, the beach was threatened by repeated visits of `sand pirates' who removed sand from the beach for sale to artificial stone manufacturers in San Francisco. They regularly removed 50 to 100 tons of sand per load. Large portions of the beach were soon characterized by rock and mud as the overlying sand was stripped away. Beginning in the late 19th century the salt marsh in the lee of Point San Mateo was reclaimed from the Bay to create agricultural land. At this time the land formed part of the Rancho San Mateo. An embankment was constructed that stretched from the southern tip of the headland, south to beyond the mouth of San Mateo Creek and around the city limit of San Mateo at that time. This effectively stopped tidal inundation of the entire salt marsh behind Point San Mateo. The remnant creeks remained transecting the low-lying reclaimed area. The low-lying partly reclaimed, but still wetland plain was effectively the landscape in 1922 when Pacific City Amusement Park was constructed on the reclaimed surface adjacent to the north shore, west of Point San Mateo. Two of the parks main attractions were a boardwalk at the top of the beach and a pier stretching out into the Bay from the central section of the beach (Figure 6). In order to make the beach attractive to visitors, around 2,000 tons of sand from Monterey was used to nourish the beach. Much of this sediment has now been lost, presumably offshore or to the east around Point San Mateo. In 1940 San Mateo County Parks and Recreation Department purchased 727 acres at Coyote Point, around 329 acres of which was subtidal. Except for the beach used by swimmers, park development was

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not immediately undertaken. Between the purchase and development of the land as a park, the majority of the Recreation Area was filled with imported material. To counter long-term erosion of the beach and frontage, sand nourishment took place between the 1960s and 1980s. In the 1960s, sediment was imported from the construction of Highway 101. However, it is believed the particle size of the sand was too fine and it was soon lost from the beach. In the 1970s and 1980s, a mix of pea gravel, sand and Bay mud was used to counter loss of the beach. In the 1990s the coastal structures were constructed at the top of the beach. Today, local windsurfers note that the piles supporting the old Pacific City boardwalk have historically been covered by beach sediment. However, over the last two years, the piles have become exposed and their tops are now sitting a few feet proud of the beach surface. This lowering of the beach has likely contributed to the undermining of the structures by allowing higher wave energies to impinge at their bases. In addition, lowering of the beach has exposed the underlying substrate at the top of the beach along its eastern section. 2.3 BATHYMETRY

The bathymetric contours of the San Francisco Bay offshore from Coyote Point Recreation Area are generally aligned northwest-southeast, parallel to the main subtidal channel of the South Bay (Figure 1). As the shoreline is approached the contours bend into a west-northwest alignment sub-parallel to the shoreline orientation. The contours close inshore must bend further into an east-west alignment to parallel the local Coyote Point Recreation Area frontage. Water depths in the main channel north and northeast of Coyote Point reach up to -35 ft mean lower low water (MLLW). Across the shallower subtidal zone west of the channel, water depths shallow from -15 ft MLLW approximately two miles northeast of Coyote Point to -6 ft MLLW approximately one mile offshore. 2.4 TOPOGRAPHY

A topographic (and nearshore bathymetry) map (Figure 7) was prepared for this study using 1 inch = 300 ft scale color aerial photography that was flown February 17, 2007 (Figure 2), and a ground survey of the beach, the Recreation Area grounds and key features carried out on March 26, 2007 (Figure 8). Using photogrammetric computer aided drafting techniques; a 1 inch = 40 ft map with one foot contours was produced that shows the significant planimetric features, such as the promenade, buildings and coastal structures. The topographic mapping used the California Coordinate System Zone 3, NAD 83 as the horizontal datum and NAVD 88 as the vertical datum. The map includes the coastal portion of Coyote Point Recreation Area between the headland to the east, the western end of the Armor Flex to the west, and to 600 ft landward of the structures. PWA collected nine shore-normal beach profiles (transects 1-9) and a single transect (10) along the seaward edge of the promenade using a Total Station (Appendix B). The shore-normal transects stretch from below mean low water (wading depth at low tide) to the promenade surface across the coastal structures, and into the Recreation Area (Figure 8). Vertical and horizontal control was provided by the

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control points used by the aerial photography flight. The elevations of key structures are presented in Table 3-1. Table 3-1. Elevations of Key Structures Site Feature Top of beach (west) Top of beach (center) Top of beach (east) Promenade (seaward edge) Promenade (landward edge) Open grassland East car parking lot West car parking lot Restrooms footing Kite and windsurfing retail outlet footing Animal rescue center

Note: see Table 3-3 for tidal elevations

Elevation (ft NAVD 88) 4.2-4.6 6.0-6.6 7.8-9.8 10.3-11.0 10.7-11.3 5.8-18 8.3-11 9-11 13.2-13.4 12.4-12.9 8.2-8.9

2.4.1

Beach

The beach transects show that the general morphology of the beach is consistent from east to west, comprising a steeper upper beach (foreshore) and a shallower subtidal lower portion; the boundary marked by a break in slope (Appendix B). However, the beach dimensions vary in an east-west direction. The beach narrows from approximately 140 ft its eastern end (between the top of the beach and the break in slope) to approximately 50 ft at its western end (Table 3-2). The height of the top of the beach lowers from approximately 9.8 ft NAVD at the eastern end to 4.2 ft NAVD at the western end. The break in slope is higher at the western end (approximately 0.5 ft NAVD) than the eastern end (-0.8 ft NAVD). However, the beach gradients along the entire frontage are generally consistent between 1:15 and 1:13 (Appendix B and Table 3.2).

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Table 3-2. Beach Dimensions Transect Width (ft) No. 1 142 2 119 3 118 4 98 5 104 6 65 7 53 8 51 9 N/A

Top Height (ft NAVD 9.78 7.85 7.87 5.96 6.61 4.55 4.46 4.18 N/A

Break Height (ft NAVD) -0.83 -0.50 -0.55 -0.65 -0.42 -0.04 0.44 0.52 N/A

Gradient 1:13 1:14 1:14 1:15 1:15 1:14 1:13 1:14 N/A

The beach transects allow us to divide the beach at Coyote Point Recreation Area into three general eastwest sections. The eastern portion, in the lee of the headland, is higher (7.8-9.8 ft NAVD at the top) and wider (120-140 ft) between the promenade curb and the break in slope. The central section of beach reaches an elevation of approximately 6.0 to 6.6 ft NAVD at the collapsed curb and is approximately 100 ft wide. The western section of upper beach, fronting the riprap and Armor Flex, is the lowest and narrowest section, with a top height of 4.2 to 4.6 ft NAVD and a width of 50 to 70 ft. In general, an extension of the beach slope inland would result in a shoreline retreat of approximately 50 ft. The eastern end (transect 1) is the exception with the promenade extending only about ten feet seaward of the potential beach surface. 2.4.2 Structures and Promenade

The asphalt surface of the promenade has elevations between 10.3 and 11.3 ft NAVD. The coastal structures (rock riprap, Armor Flex articulated block mat, reinforced concrete) drop down from these elevations to the elevation of the beach immediately in front of them. 2.4.3 Recreational Area

The open grassed areas occupy the central part of the Recreation Area and vary in elevation from to 5.8 to 18 ft NAVD (Figure 7). The lowest point adjacent to the promenade is at approximately 11.2 ft NAVD, landward of which is lower-lying ground down to 8.2 ft NAVD. The asphalt surface of the east car parking lot slopes from north to south from approximately 11 ft NAVD at the promenade to 8.3 ft NAVD at its southern tip. The west car parking lot is generally slightly lower than the adjacent promenade and varies in elevation from approximately 9 to 11 ft NAVD. The restrooms and retail outlet are slightly raised above the surrounding profile, with their bases at approximately 12.4 to 13.4 ft NAVD. The grounds along the eastern side of the animal rescue center are at elevations between 8.2 and 8.9 ft NAVD, slightly lower than the surrounding terrain.

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2.5

TIDAL WATER LEVELS

The Bay-side shoreline of San Mateo County experiences mixed semidiurnal tides, with two high and two low tides of unequal heights each day. In addition, the tides exhibit strong spring-neap tide variability; spring tides exhibit the greatest difference between high and low tides while neap tides show a smaller than average range. The NOAA tidal datums for the 1983-2001 epoch for the west side of San Mateo Bridge are summarized in Table 3-3. The mean tidal range (defined as Mean Low Water minus Mean High Water) is 5.9 ft and the diurnal range (defined as MHHW minus MLLW) is 7.7 ft. Table 3-3. NOAA Tidal Datums (1983-2001 Epoch) for San Mateo Bridge (West Side) Tide Gauge MLLW (ft) NAVD 88 (ft) 7.72 7.12 MHHW 7.09 6.49 MHW 4.14 3.54 MTL 1.19 0.59 MLW 0 -0.6 MLLW

2.6

100-YEAR COASTAL FLOODPLAIN

Parts of the Recreation Area are located within the 100-year coastal floodplain as determined by the Federal Emergency Management Agency (FEMA, 2001). FEMA (2001) estimated the 100-year coastal flood level (base flood elevation) to be at an elevation of 7 ft NGVD (approximately 9.7 ft NAVD) (we used VERTCON to convert from NGVD to NAVD). This level is lower than the lowest point along the promenade (10.3 ft NAVD) but higher than much of the grassed area and parking areas (Figure 7). Since the shoreline armoring is not certified to protect to the 100-year event, the shoreline is considered by FEMA to be in the floodplain. FEMA is expected to update the flood hazards within the next ten years. The City of San Mateo is pursuing a project to increase flood protection by raising Bay levee crest elevations. Their plan includes a raised berm across the Park to connect to City levees to the west (Schaaf and Wheeler Consultants, 2006). This element would require County action. 2.7 FUTURE RELATIVE SEA-LEVEL RISE

IPCC (2007) reported climate change simulations (using a variety of atmosphere-ocean general circulation models and a suite of greenhouse gas emissions scenarios) that project global sea-level rise over the next century due to thermal expansion as the oceans warm and changes in ocean mass due to exchanges of water with glaciers, ice sheets, groundwater, or atmosphere. IPCC (2007) predicted a global average sea-level rise between 1990 and 2100 of 0.6-1.9 ft, although considerable uncertainty surrounds these values. For example, Rahmstorf (2007) used a linear semi-empirical relationship between observed rates of sea-level rise and global mean surface temperature for the 20th century to project higher rates of sea-level rise between 1.6 and 4.6 ft during the 21st century.

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The rate of subsidence at Coyote Point has been estimated at 0.06 ft over the last 20 years, equating to 0.30 ft/century. This estimate is based on the average subsidence from three benchmark locations along Old Bayshore Highway (south of San Francisco Airport), surveyed by Towill, Inc. in October 1996. Based on historic benchmark elevation data, BCDC (1988) estimated a subsidence rate of 0.20 ft/century at the west side of San Mateo Bridge. Assuming a 0.20-0.30 ft/century rate of subsidence at Coyote Point, then combining global sea-level rise with the predicted subsidence rate, gives a future relative sea-level rise at Coyote Point of approximately 0.8 to 2.2 ft/century. For planning purposes, a relative sea-level rise of 0.5 ft in 50 years and 1.5 ft in 100 years will be used. 2.8 WIND-WAVES

The predominant wind directions at San Francisco International Airport are from the west and northwest with wind speeds often exceeding 25 mph (Figure 9). Less frequent storm events with high wind speeds (in excess of 25 mph) often have a southerly or easterly component, though the north-facing Recreation Area frontage is relatively unaffected by wind-waves from these directions. Winds from the north and northeast, however, are responsible for generating the most extreme wind-wave conditions because of the relatively long fetch (Figure 10). The predominant northwesterly winds have a much shorter fetch length. Moffatt & Nichol (1992) Moffatt & Nichol and PWA (1998) used wind fetches, water depths and diffraction techniques to transform wave heights and periods from deep water to shallow water to estimate the wave characteristics at the Coyote Point Marina. They reported wave heights and periods of 3.3-3.9 ft and 4.2-4.6 seconds, respectively, for a return period of 25 years. These estimates apply to the Coyote Point Marina immediately east of the Coyote Point headland, and therefore are slightly higher than those associated with the more sheltered shoreline to the west. Noble Consultants (1999) compiled monthly wind velocity (speed and direction) data from San Francisco Airport between 1978 and 1998. Maximum annual wind speeds were compiled from the data ranging from 18 to 46 mph, with an average of 29.5 mph, over the 21 year period. They used a wind speed of 30 mph approaching the frontage from a northerly direction to calculate a wave height of 3.0 ft and a wave period of 4.0 s at the shore. Schaaf and Wheeler Consultants (2006) developed wind-wave and flood elevation estimates for the City of San Mateo and their proposed new coastal Bayfront Levee Improvement application to FEMA. 2.9 TIDAL CURRENTS

Tate et al. (2001) showed that tidal current flows are dominantly east-west and follow the curvature of the bathymetry offshore of Coyote Point Recreation Area. Throughout the year the mean hourly current speed was 0.18-0.19 m/s (0.59-0.62 ft/s), with maximum speeds of 0.37-0.44 m/s (1.21-1.44 ft/s).

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2.10

SEDIMENT SUPPLY AND TRANSPORT

Prior to major development impacts around south San Francisco Bay, it is likely that the Coyote Point Recreation Area frontage was supplied by sediment from stream discharge and erosion of the coast to the north, carried by a net southerly longshore sediment transport. In the late 19th century the beach appeared to be healthy and possibly backed by low dunes, indicating sufficient sediment supply (Figure 5). However, major construction including San Francisco International Airport and its surrounds has meant that this supply of sediment has been substantially reduced. The east-southeasterly and southeasterlydirected wind waves continue to drive sediment to the east along the Coyote Point frontage, but the sediment is now mainly reworked from within the sediment cell along the Coyote Point Recreation Area frontage west of Coyote Point headland. This transport mechanism leads to a deficit of sand along the beach (especially along the central and western portions). Coyote Point headland controls the shoreline along the eastern portion, resulting in less shoreline retreat along this section. Unless sand is added to the shoreline, we expect erosion to continue. It appears that the filled and armored shore cannot be maintained without extensive buttressing of the armor. Unless the shore is realigned, we anticipate further loss of beach resulting in only a low-tide pocket at the eastern end. This is reflected in the widths and elevations of each of these sections of beach as described in Section 2.4.1.

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3. DESIGN CRITERIA

Although the Coyote Point shoreline is eroding, it is unable to migrate landward with this process because it is constrained by the coastal structures. These structures hold the coastal planform in a position seaward of the position it would take if the shoreline was allowed to equilibrate with the physical processes controlling its shape. In this section we analyze design criteria to setback the shoreline to a position and elevation that is sustainable and in equilibrium with the forcing wave processes. 3.1 3.1.1 SHORELINE PLANFORM Crenulate Shaped Bays

A coast with no sediment supply between two erosion-resistant points (headlands or coastal structures) will readjust its shape to an orientation that is perpendicular to the main wave direction. The natural equilibrium form of this type of shoreline is crenulate shaped (Figure 11) and may be classified as either in static equilibrium or dynamic equilibrium (Silvester and Hsu, 1997; Hsu et al., 2008). A static equilibrium bay-beach has near zero longshore sediment transport or near zero sediment input or output. Within this bay waves are refracted and diffracted around the headland or coastal structure and approach the beach perpendicularly (Figure 11). In a dynamic equilibrium bay-beach, a balance between sediment input and sediment output maintains the bay planform at its equilibrium position. This type of bay-beach generally occurs where a river enters into the closed cell between the headlands or when the boundaries of the bay-beach allow sediment bypassing. Figure 12 shows examples of natural crenulate shaped bays along the coast of California. The current planform shape of the Coyote Point Recreation Area shoreline is unstable. Beach reshaping should be taking place, but it is constrained by the presence of the coastal structures, which are not allowing the natural crenulate shaped form to occur. The beach is not being allowed to migrate in a landward direction; it is eroding and steepening, and being squeezed between a rising sea level and the structures. Given the lack of sediment supply, the stable planform position of the Coyote Point Recreation Area frontage, would be a crenulate shaped bay in static equilibrium (Figure 11). Recognizing the physical and sedimentary processes that are operating at the site we have developed a series of conceptual project alternatives, which entail creation of one or two crenulate shaped bays between the Coyote Point headland and the Bay Trail. We recognize that the preferred crenulate shaped bay(s) configuration will be partly controlled by other factors such as constraints related to beach access, car parking space etc., and these are outlined in our discussion of a preferred alternative in Section 5.

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3.1.2

Parabolic Bay Shape Equation

Crenulate bay stability and design of static equilibrium bay-beaches using a parabolic bay shape equation have been analyzed by Hsu and Evans (1989), and we use their criteria in this study. The equation, derived from empirical analysis of prototype and model bays, is as follows: Rn/R = Co + C1(/n) + C2(/n)2 The two basic parameters are the reference angle of wave obliquity () and control line length RB (Figure 11). Parameter is the angle between the incident wave crest (assumed linear) and the control line (R), which joins the upcoast diffraction point to a point on the near straight downcoast beach. The control line length (R) is also angled B to the tangent of the beach at the downcoast end of the crenulate shaped bay. The radius Rn to any point on the bay periphery in static equilibrium is angled n from the same wave crest line radiating out from the point of wave diffraction upcoast. The three C constants vary with angle and are presented in Silvester and Hsu (1997). Once the two basic parameters, and R are known, values for pairs of Rn and n are calculated for a bay in static equilibrium under the same wave approach direction. The idealized bay planform can then be constructed. If there is a sediment supply, the shape of the shore will change by widening seaward, and rotating at the downcoast control. 3.1.3 Direction of Wave Approach and Reference Angle of Wave Obliquity

To calculate the dominant direction of wave approach at Coyote Point Recreation Area we used wind data between 1964 and 2005 from San Francisco Airport (obtained from the National Climatic Data Center). A wind rose (Figure 9) was constructed using annual frequencies of occurrence of hourly 2-minute wind measurements. Offshore wave energies were computed from a wind speed-duration curve generated using the relationship in Figure 3-13 of the Shore Protection Manual (Corps, 1984). Fetch length and depth were estimated for each direction corresponding to the wind measurements (every 10o). A wave hindcast model (WAVE98, PWA software), accounting for the directional wave spectra, was used to compute the windgenerated wave heights (H) and periods (T) for the given wind speed and duration, and fetch length depth for all directions. WAVE98 estimates wave height and period using empirical methods described in Chapter 3 of the Shore Protection Manual (Corps, 1984) and Part 2 of the Coastal Engineering Manual (Corps, 2002). The software also uses the spectral contribution method of Seymour (1977). Wave energy was calculated as H2T, and then multiplied by the relative frequency of occurrence to generate offshore wave energy. Nearshore wave energies were estimated (Figure 13) by transforming the computed offshore wave heights and periods from deep water to shallow water for all directions within 90o of shore normal (estimated to be 340o). Transformation of the waves from deep to shallow water assumed linear wave theory, and the dispersion relationship was solved iteratively for each wave direction. The nearshore wave energy was scaled by the relative frequency of occurrence for the initial offshore direction, resulting in the nearshore

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wave power plot shown in Figure 13. Note that the units (H2T = ft2s) are not units of power because several constants have not been applied. The values are therefore called wave power index and represent the amount of wave power incident to the shore from each direction on an average annual basis. The predominant direction of wave energy is west of shore-normal, indicating that the beach at Coyote Point is not in equilibrium and there is a potential longshore sand transport from west to east. The nearshore wave energy plots show the highest frequency of waves approach from 310oN. We have adjusted this direction to 325oN to account for sediment transport, whereby the crenulate planform shape would rotate clockwise at its downcoast control point. This dominant direction (325oN) in combination with the control line angles for each conceptual bay was used to determine the reference angle of wave obliquities. 3.1.4 Control Line Length

Control line lengths (which join the upcoast and downcoast hard points) were calculated based on the number and size of the bays conceived for each conceptual alternative. The longer the control line is, the deeper the crenulate shaped bay will cut into the existing Recreation Area land. 3.2 SHORELINE CROSS-SECTIONAL PROFILE

Even though a wide variety of troughs and ridges (berms, ridges and runnels, longshore bars) may be present on any beach profile, and the profile may change seasonally due to changes in wave climate, the most important morphological feature is the average slope between the seaward and landward limits. The backshores of many beaches usually possess a flat-topped ridge or bar known as the berm that forms at the limit of wave runup. Hence, the cross-sectional profile of the crenulate bay(s) will comprise two main components; the elevation and width of the backshore berm and the slope of the foreshore. 3.2.1 Backshore Berm Elevation and Width

In order to estimate the elevation of the berm we have used the runup calculations of Schaaf and Wheeler Consultants (2006) for the Bayfront Levee Improvement project immediately to the west of our study frontage. Using the San Francisco Airport wind data from 1978 to 1998 they estimated a 1 in 100 year wave runup (maximum wave runup plus tidal elevation) of 9.5 ft NGVD1 (approximately 12.2 ft NAVD) (Figure 14). This elevation is used as the conceptual revetment height (Figure 15). For the natural beach, we estimate a typical berm elevation of 10 ft NAVD and 50 ft minimum beach width to provide buffer during storms and provide sufficient area for beach recreational activities. The berm elevation estimate is based on the beach forming runup with a return period of one to five years.

1

Wave setup appears not to have been analyzed by Schaaf and Wheeler Consultants (2006). In their analysis, calculation of wave setup is actually wave height. In this respect, it is possible that total water elevation is underestimated because setup has not been considered.

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3.2.2

Foreshore Slope

Conceptual foreshore slopes were constructed by connecting the beach berm elevation to the elevation of the break in slope at the base of the existing foreshore (derived from our shore-normal beach profiles, Appendix B) (Figure 15). Foreshore slopes were constructed based on the shore-normal width of the bays conceived for each conceptual alternative. At this stage the particle size characteristics of the beach are not known, and hence these slopes may need to be adjusted when these data are available.

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4. FORMULATION AND EVALUATION OF ALTERNATIVES

Six conceptual alternatives based on the design criteria described in Section 3 are summarized in this section with their opportunities and constraints. The descriptions provide enough information to facilitate comparison and identify key design issues (Figure 16 to 20). 4.1 4.1.1 ALTERNATIVES Alternative 1: No Action

This alternative would leave the site to evolve from its present condition without any intervention. The beach would continue to erode leading to further exposure of the underlying substrate, loss of sand, and undermining and collapse of the coastal structures. This would exacerbate erosion of the promenade (leading eventually to its total loss) and access to the beach would be increasingly difficult for recreational activities. The aesthetic appeal of the frontage would be significantly diminished due to the unsightly nature of the collapsing structures. 4.1.2 Alternative 2: Maintain Shoreline Armoring in its Current Position

This alternative entails reconstruction of the promenade structures (riprap or vertical seawall) along their current alignment (Figure 16), with maintenance carried out at regular intervals. This alternative could be combined with recurring nourishment east of the retail outlet to create a recreational beach. Figure 17 shows the potential configuration of this type of shoreline (Coyote Point Marina breakwater). Opportunities Coastal structures would be maintained to protect the frontage and enable the promenade to remain in its current position. The shoreline would not be setback with no loss of land area, including car parking lots, open areas, buildings, and windsurfing rigging areas. The retention of the structures west of the retail outlet and a narrower beach would be favorable for windsurfing access to the water. Constraints The beach alignment would remain in an unstable and unsustainable position leading to continued beach erosion and further risk of damage to structures. Continued erosion would lead to further loss of sand from the beach, reducing its recreational value, particularly for swimmers and sunbathers east of the retail outlet. Removal and reconstruction of 2,000 ft of seawall or riprap, and repaving of the promenade would be expensive.

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This alternative would require constant maintenance of the structures to retain their protective standards. The structures would limit public access to the beach and the water. The continued presence of structures would compromise the aesthetic value of the coastal frontage for visitors. Maintenance of a summer beach east of the retail outlet would require ongoing sand placement 4.1.3 Alternative 3: Crenulate Shaped Bay Between the Bay Trail and Coyote Point Headland

This alternative removes the existing structures and realigns the shoreline between the Bay Trail and Coyote Point headland to a position setback from its current position (Figure 18). This would create a single crenulate shaped bay held by Coyote Point headland to the east and an artificial hard point constructed to the west. This alternative would be combined with beach nourishment within the crenulate shaped bay cell. Opportunities The crenulate shaped bay would create a shoreline in static equilibrium and sustainable over the long term. The beach would be long and wide, and attractive for beach recreational activities, including swimming and sunbathing. Beach nourishment could reduce loss of land by reducing the amount of setback into Recreation Area land. Constraints This alternative would entail a setback of the shoreline of approximately 300 ft at its widest point, removing approximately 10 acres of land area. The bay planform would result in loss of the east and west car parking areas, and require removal or relocation of the promenade and all of the buildings along the coast, including the animal rescue center, kite and surf retail outlet and restrooms. Removal of approximately 10 acres of land fill and acquisition, transport, and placement of large quantities of sand to create the summer beach would have a high cost. A wide sandy beach across the western portion of the frontage would be unfavorable for windsurfing access to the water. 4.1.4 Alternative 4: Crenulate Shaped Bay Between the Bay Trail and the Retail Outlet

This alternative removes the existing structures and realigns the shoreline to a position setback from its current position between the Bay Trail and the retail outlet (Figure 19). The coastal structures to the east of the retail outlet would be maintained along their present alignment. The crenulate shaped bay would be held in position by two artificial hard points located close to the Bay Trail and retail outlet. This alternative would be combined with beach nourishment within the crenulate shaped bay cell.

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Opportunities The crenulate shaped bay would create a shoreline in static equilibrium and sustainable over the long term west of the retail outlet. The beach would be attractive for beach recreational activities. Constraints The beach alignment east of the retail outlet would remain in an unstable and unsustainable position leading to continued beach erosion and risk of damage to structures. Continued erosion east of the retail outlet would lead to further loss of sand and reduction of the beaches recreational value. This alternative would require constant maintenance of the structures east of the retail outlet to retain their protective standards. The structures east of the retail outlet would limit public access to the beach and the water. The setback would result in loss of the entire west car parking area and the windsurfing rigging area, and would impinge on the promenade and animal rescue center. The stretch of water west of the retail outlet is restricted to the use of windsurfers and a wide sandy beach would be unfavorable for their access to the water. Creation of a wide beach west of the retail outlet would likely preclude its use for windsurfing and would necessitate a change of use to swimming or other beach recreational activities. The setback would require placement of sand to create the beach. 4.1.5 Alternative 5: Crenulate Shaped Nay Netween the Retail Outlet and Coyote Point Headland

This alternative removes the existing structures and realigns the shoreline to a position setback from its current position between the retail outlet and Coyote Point headland (Figure 20). The coastal structures to the west of the retail outlet would be maintained along their present alignment. The crenulate shaped bay would be held in position by an artificial hard point located close to the retail outlet, and by Coyote Point headland. This alternative would be combined with beach nourishment within the crenulate shaped bay cell. Opportunities The crenulate shaped bay would create a shoreline in static equilibrium and sustainable over the long term east of the retail outlet. The beach would be attractive for beach recreational activities, including sunbathing and beach sports, and provide good access to the water for swimmers. The retention of the structures west of the retail outlet resulting in a narrow beach would be favorable for windsurfing access. The shoreline would not be setback west of the retail outlet so the west car parking lot and windsurfers rigging areas would be retained.

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Beach nourishment could reduce loss of land by reducing the amount of setback into Recreation Area land. Constraints The beach alignment west of the retail outlet would remain in an unstable and unsustainable position leading to further beach erosion and risk of damage to structures. This alternative would require constant maintenance of the structures west of the retail outlet to retain their protective standards. The setback would result in loss of part of the east car parking area, and require relocation of the promenade and removal or relocation of the restrooms. The setback would require placement of sand to create the beach. 4.1.6 Alternative 6: Crenulate Shaped Bays Either Side of the Retail Outlet

This alternative removes the existing structures and realigns the shoreline in two locations; between the Bay Trail and the retail outlet and between the retail outlet and Coyote Point headland. This alternative would create two crenulate bays of similar size (Figures 19 and 20) either side of the retail outlet. This alternative would be combined with beach nourishment within both crenulate shaped bay cells. Opportunities The crenulate shaped bays would create shorelines in static equilibrium and sustainable over the long term. The beaches would be attractive for beach recreational activities. Constraints The setbacks would result in loss of part of the east car parking area and loss of the entire west car parking area, and windsurfers rigging area, and would impinge on the promenade and animal rescue center property. The stretch of water west of the retail outlet is restricted to the use of windsurfers and a wide sandy beach would be unfavorable for their access to the water. Creation of a wide beach west of the retail outlet would likely preclude its use for windsurfing and would necessitate a change of use to swimming or other beach recreational activities. The setbacks would require placement of sand to create the beaches. 4.1.7 Options

The conceptual alternatives outlined above are based on the use of three convenient locations (Bay Trail, retail outlet and Coyote Point headland) as potential hard points for the creation of one or two crenulate shaped bays. In our discussion of the preferred alternative (Section 5), we highlight potential changes to the size(s) of the bay(s) and/or positions of the bay(s) hard points that could alleviate some of the constraints related to infrastructure (e.g. car parking) and access (e.g. windsurfers) across the site.

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5. PREFERRED ALTERNATIVE

Section 4 outlines the opportunities and constraints related to six conceptual alternatives for the restoration of the Coyote Point Recreation Area coastal frontage. Alternative 1 (no action) and Alternative 2 (`hold-the-line') are rejected because both are unsustainable. Both these alternatives would lead to continued erosion of the beach, exposure of the underlying substrate, loss of sand, and potential undermining and collapse of the coastal structures. Two critical aspects of the remaining four alternatives are the requirement for easy access to the water for swimmers and windsurfers, and the desire to maintain, as far as possible, the current number of car parking spaces. In this section, we consider these factors in more detail (along with the design criteria), in our selection of the preferred alternative. 5.1 OPTIONS WITH A CRENULATE SHAPED BAY WEST OF THE RETAIL OUTLET

Currently, the western section of the shoreline is restricted for the use of windsurfers, whilst the eastern section is restricted to beach users and swimmers. Windsurfers require space to rig their boards and sails, and prefer direct quick access to the water, without the need to cross a wide sandy beach. The existing condition west of the retail outlet is suitable for windsurfers because it meets the access criteria and there is suitable rigging space landward of the promenade. Creation of a crenulate shaped bay-beach between the Bay Trail and the retail outlet would remove the rigging locations (Figure 19) and would make access to the water more difficult. Car parking space close to the shoreline is restricted to the east and west car parking lots (Figure 2). Availability of space elsewhere in the Recreation Area for new parking areas is limited if the current parking lots are removed. Creation of a bay between the Bay Trail and the retail outlet would completely remove the west car parking lot (Figure 19), resulting in the loss of approximately 170 parking spaces. It is unclear whether these spaces could be constructed elsewhere within the park. Because of the constraints to the windsurfing community, who are an important stakeholder in the management process at Coyote Point Recreation Area, and the loss of large numbers of car parking spaces, which are important for the future use of the site, we rule out the following conceptual alternatives described in Section 4: Alternative 3: Crenulate shaped bay between the Bay Trail and Coyote Point headland Alternative 4: Crenulate shaped bay between the Bay Trail and the retail outlet Alternative 6: Crenulate shaped bays either side of the retail outlet

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5.1.1

Option to Create a Pocket Beach (Option 4a)

Although the proposed configurations of Alternatives 3, 4, and 6 are not favored based on the criteria outlined above and the constraints listed in Section 4, there is a potential change that could be made to reduce the size of a crenulate shaped bay west of the retail outlet. This Option 4a would reduce the control line length (length between the upcoast and downcoast hard points), which in turn, would reduce the indentation of the crenulate shaped bay into the Recreation Area, creating a smaller pocket beach (Figure 21), that could be used by windsurfers as an entry point to the water. In order to provide suitable windsurfing access to the water, gaining the full benefit of the predominant wind direction and shoreline orientation, the pocket beach would need to be as far to the west as possible. However, a position towards the west end of the Armor Flex would still lead to loss of substantial numbers of parking spaces and loss of windsurfing rigging areas. A position immediately to the west of the retail outlet would lead to minimal loss of parking area, but would not be suitable for windsurfer access and would also attract beach goers and swimmers into an area typically used by windsurfers. This would have safety implications caused by conflict of users (particularly children in the vicinity of windsurfing boards and sails). In addition, and regardless of specific location, the pocket beach option would require constant maintenance of the structures to either side (likely to be riprap or vertical seawall) to retain their protective standards (similar to Alternative 2). Because of the difficulties of finding a suitable location for a pocket beach west of the retail outlet, and the need for a large amount of structure maintenance, Option 4a is not favored. 5.2 OPTIONS WITH A CRENULATE SHAPED BAY EAST OF THE RETAIL OUTLET

The main constraint with respect to a crenulate shaped bay between the retail outlet and Coyote Point headland would be the loss of most of the east car parking lot (Figure 20). Most of this loss would be caused by removal of Recreation Area land at the east end of the bay towards the headland. 5.2.1 Option to Shift Crenulate Shaped Bay to the West (Option 5a)

A potential way to alleviate most of the loss of car parking space would be to shift the entire planform profile of the crenulate shaped bay to the west (Option 5a, Figure 22). This shift would retain the size and shape of the bay, but would place the widest part of the bay over the retail outlet, which would need to be removed or relocated. There are several constraints associated with Option 5a. First, shifting the crenulate shaped bay to the west would attract beach goers and swimmers into an area typically used by windsurfers, causing a conflict of use. Second, the existing west car parking lot would become a close access point to the protected beach area, and hence parking conflicts would be likely; it would be prudent to maintain a distinction between the windsurfers and swimmers parking areas. Third, this option would require armoring to the east of the crenulate bay between the downcoast hard point and Coyote Point headland.

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Because of the potential for conflict of users (both parking and beach use) and its safety implications, Option 5a is not favored. 5.2.2 Option to Shift Crenulate Shaped Bay to Seaward (Option 5b)

Another potential way to alleviate loss of car parking space would be to shift the crenulate shaped bay to seaward (Option 5b, Figure 23). This would require construction of artificial hard points (breakwaters) at the upcoast and downcoast ends in order to confine the sand, adding significantly to the cost of the project. Although, the volume of beach fill required to construct and maintain the beach would be greater, the amount of excavated material generated would be less. Construction of breakwaters into the Bay and beach construction over the nearshore intertidal part of Bay the entails fill above a minimum level, and would require a more extensive environmental permitting and review process. We understand that the County anticipates simplified environmental review (a Negative Declaration or Mitigated Negative Declaration, consistent with the Park Master Plan and existing permits) and an administrative amendment to the existing San Francisco Bay Conservation and Development Commission (BCDC) permit. Option 5b is unlikely to be viable with this approach, because the option would require more detailed environmental review, such as an EIR, and a new BCDC permit. Therefore, Option 5b entails more extensive effort and a longer time frame not presently programmed. Because of the potential additional costs associated with breakwater construction and the need for an extensive and likely time-consuming environmental review process, Option 5b is not favored. 5.2.3 Cost Estimates for Alternative 5 and Options 5a and 5b

A summary of the opinions of probable costs of construction for Alternative 5, Option 5a and Option 5b is presented in Table 5-1, with detailed break downs in Appendix C. The opinions of probable costs provided are made on the basis of PWA's qualifications and experience. The actual cost will be affected by the availability of construction equipment and crews at the time the work is accomplished. Please note that in providing opinions of probable costs, PWA has no control over costs or the price of labor, equipment or materials, or over the contractor's method of pricing. PWA makes no warranty, expressed or implied, as to the accuracy of such opinions as compared to bids or actual costs. Estimated costs are presented in 2007 dollars, and would need to be adjusted to account for price escalation for implementation in future years. The estimated costs of plans and environmental review as provided by the County are also shown in Table 5-1.

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Table 5-1. Opinions of Probable Costs of Construction for Alternative 5, Option 5a, and Option 5b Alt 1 Option 5a Option 5b Construction estimate Construction estimate w/ 25% contingency Plans and environment review Total $2.6 million $3.2 million $0.5 million $3.7 million $4.0 million $5.0 million $0.7 million $5.7 million $2.9 million $3.6 million $0.7 million $4.3 million

Costs of new landside facilities are approximately estimated (Appendix C) pending estimates by the County. 5.3 5.3.1 PREFERRED ALTERNATIVE Alternative 5 to the East of the Retail Outlet

The creation of a crenulate shaped bay east of the retail outlet using Coyote Point headland as the downcoast hard point, is our recommended alternative for this portion of the frontage. Alternative 5 is the best balance of opportunities and constraints, presuming that new parking area(s) are constructed to maintain existing levels of access. We anticipate that there will be further refinement during the design phase to minimize the reduction in area of park upland, maintain existing number of parking spaces, and confirm support by park users and BCDC. We also recommend that additional funding be pursued for design and construction, consistent with the importance of the Recreation Area and the opportunity to improve it in a sustainable manner. The exact size and orientation of the bay are to be determined, although a relatively large rather than a relatively small (pocket) beach is favored. Access to the beach would be by steps from a promenade reconstructed along the landward edge of the crenulate shaped bay. We envisage two or three access points along the length of the back beach. The beach would be used for recreational activities excluding windsurfing. This alternative would lead to loss of the east parking lot, and additional parking spaces would need to be found elsewhere. It may be possible to create a single layer of parking adjacent to the crenulate bay edge in the large grassed area behind the current retail outlet. San Mateo County Water Pollution Prevention Program is interested in the project and has encouraged County Parks to apply for funding (~$250,000 non-competitive grant) to make a Countywide `green' parking lot demonstration project to reconstruct parking lots as models for storm water pollution best management practices (BMPs). These BMPs would involve permeable paving, sloping lots and landscaping into swales to avoid direct runoff to storm drains and the Bay. The creation of the crenulate shaped bay would benefit the City of San Mateo's Bayfront Levee Improvement project by providing fill that could potentially be used in construction. This would involve

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re-landscaping portions of Coyote Point Recreation Area to meet flood control objectives, which would provide a cost saving over disposal off-site. 5.3.2 Alternative 5 to the West of Retail Outlet

Armoring the frontage west of the retail outlet, potentially in combination with access ramps, would provide a solution for windsurfers and is our recommended alternative. The type and geometry of armoring are to be determined, but a preference for Armor Flex-coated riprap because windsurfers could then utilize the Armor Flex surface along the entire length of the structure without the need for access ramps. With a riprap surface the windsurfers would need two or more ramps for access because they cannot use the rock itself. The ramps would need to be shallow sloped and at least 30 ft wide. Riprap with an Armor Flex overlay would also mitigate the potential for slumping and collapse phenomena as developed over the last few years (Figure 3). The length of the double layer structure is to be determined. To provide a shallow slope on the Armor Flex without building out into the Bay would need the armoring to be moved landward. This would then require the promenade to relocate south with the structure which removes some of the west parking lot. An area of mounded earth immediately to the east of the Animal Rescue Center is currently under utilized and could be used for additional parking. However, we anticipate that some Bay fill will be allowed in order to maintain public access (including parking) and in consideration of the net removal of fill with the new beach. Therefore, no loss of parking is anticipated in the western part of the Park. 5.4 PROVISIONAL PERMITTING DISCUSSIONS WITH BCDC

Based on informal discussions, we believe that BCDC is supportive of the project, even if there is some minor area of Bay fill. The shoreline component of the Coyote Point Recreation Area is an important amenity that is highly valued by BCDC, especially if a sustainable beach can be developed for public access and the other existing uses can be maintained. However, fill into the Bay raises questions about impact to the Bay floor and existing biota, likely requiring a higher level of review and a consensus that the fill is necessary. Therefore, Alternative 5, which does not have significant Bay fill, is expected to entail less extensive environmental review and permitting as long as public access amenities such as parking and the promenade are not compromised.

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6. REFERENCES

BCDC (San Francisco Bay Conservation and Development Commission). 1988. Sea level rise: predictions and implications for San Francisco Bay. Cayan, D., Bromirski, P., Hayhoe, K., Tyree, M., Dettinger, M. and Flick, R. 2006. Projecting Future Sea Level. Report to the California Climate Change Center, March 2006. Corps (U.S. Army Corps of Engineers). 1984. Shore Protection Manual Volume 1 (2nd Printing). Corps (U.S. Army Corps of Engineers). 2002. Coastal Engineering Manual. FEMA (Flood Emergency Management Agency). 2001. FIRM Flood Insurance Rate Map. City of San Mateo, California. County of San Mateo. Graymer, R.W., Moring, B.C., Saucedo, G.J., Wentworth, C.M., Brabb, E.E. and Knudsen, K.L. 2006a. Geologic map of the San Francisco Bay region. U.S. Geological Survey Scientific Investigations Map 2918. Hsu, J.R.C. and Evans, C. 1989. Parabolic bay shapes and applications. Proceedings of the Institution of Civil Engineers, 87, Part 2, 557-570. Hsu, J.R.C., Benedet, L., Klein, A.H.F., Raabe, A.L.A., Tsai, C.P. and Hsu, T.W. 2008. Appreciation of static bay beach concept for coastal management and protection. Journal of Coastal Research, 24, 198-215. IPCC (Intergovernmental Panel on Climate Change). 2007. Climate Change 2007: The Physical Science Basis. Summary for Policymakers. Moffatt & Nichol. 1992. Coyote Point Marina: Breakwater Renovation Study. Final Report prepared for County of San Mateo, General Services Department, October 1992. Moffatt & Nichol and PWA (Philip Williams & Associates).1998. Coyote Point Marina Maintenance Projects PreDesign Report. Final Report prepared for County of San Mateo, Department of Public Works, August, 1998. Noble Consultants. 1999. Coyote Point Wave Runup. Letter Report to Church Water Consultants, June 1999.

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Schaaf and Wheeler Consultants. 2006. Wind-Wave Hazard Analysis. Additional data to support CLOMR request for City of San Mateo, California Bayfront Levee Improvements Case No: 0309-1660R. Seymour, R.J. 1977. Estimating wave generation on restricted fetches. Journal of the Waterway, Port, Coastal and Ocean Division, ASCE, 251-264. Silvester, R. and Hsu, J.R.C. 1997. Coastal Stabilization. World Scientific Publishing Co., Singapore, 578pp. Tate, G. B., Cacchione, D. A. and Israel, K. 2001. Sediment Transport and Hydrodynamic Studies near San Francisco Airport. Final Report prepared by Woods Hole Group, submitted to URS Corporation, February 2001.

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7. LIST OF PREPARERS

This report was prepared by the following staff: Philip Williams & Associates, Ltd David Brew, Ph.D., CGeol., Project Manager, Senior Associate Bob Battalio, P.E., Project Director, Principal Louis White, M.S., E.I.T., Hydrologist HJW Geospatial, Inc Peter Ashley Treadwell & Rollo, Inc Richard Rodgers

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8. FIGURES

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APPENDIX A. GEOTECHNICAL REPORT

COYOTE POINT RECREATION AREA CONCEPTUAL DESIGN REPORT - PWA Ref. # 1876 Appendices

APPENDIX B. BEACH TRANSECTS

COYOTE POINT RECREATION AREA CONCEPTUAL DESIGN REPORT - PWA Ref. # 1876 Appendices

APPENDIX C. DETAILED OPINIONS OF PROBABLE CONSTRUCTION COSTS

COYOTE POINT RECREATION AREA CONCEPTUAL DESIGN REPORT - PWA Ref. # 1876 Appendices

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