Crissy field sea level rise analysis report 2016 by Golden Gate National Parks Conservancy

CONTENTS 1.0 INTRODUCTION

2.0 SEA LEVEL RISE ANALYSIS

3.0 VULNERABILITY ANALYSIS + RISK ASSESSMENT

4.0 RISE-UP STAKEHOLDER + COMMUNITY WORKSHOP

5.0 ADAPTATION SCENARIOS

6.0 NEXT STEPS

Climate change is an enormous challenge facing our national parks. National Park Service Director Jonathan Jarvis identified climate change as “…fundamentally the greatest threat to the integrity of our national parks that we have ever experienced.” Here at the Golden Gate National Recreation Area (GGNRA), we face the potential for sea level rise, increased flooding and erosion, and changes to the ecosystems and resources we are charged to protect. The National Park Service takes very seriously its responsibility to manage the effects of climate change on our parks. This requires an understanding of the challenges we expect to face and possible strategies for responding. We recognize that decisions we make now will impact how we are able to respond to the predicted effects of sea level rise and other climate impacts in the future. That is why this sea level rise analysis for Crissy Field is an important step for GGNRA. By taking a focused look at this treasured area of the park and beginning to understand the resources that are the most threatened, we can begin to take practical steps to address some of these threats. And working with the community on this effort has given us valuable information as we look to the future.

We thank the California State Coastal Conservancy for their support of this project through a Climate Ready grant, and thank our partners at the Golden Gate National Parks Conservancy and Presidio Trust for making this effort possible.

Sincerely,

Christine Lehnertz Superintendent Golden Gate National Recreation Area

The California State Coastal Conservancy (Coastal Conservancy) as one of California’s three Coastal Zone Management Agencies is charged with protecting, restoring, and enhancing coastal resources, and providing access to the shore. The Coastal Conservancy has been working for almost 40 years to protect natural resources and human development along California’s coast and around San Francisco Bay. Much of this work has made waterfront communities, recreational and working lands, and natural areas more resilient to the effects of climate change. In 2007, the Coastal Conservancy began extensive efforts to respond to coastal climate change, adopting specific measures to address climate change in its strategic plan. In 2009, it adopted a comprehensive Climate Change Policy and also amended its Project Selection Criteria to ensure that all Conservancy projects are designed with climate change in mind. The Coastal Conservancy took these actions in response to directives from the state administration and legislature and in conjunction with many state and federal agencies and nongovernmental science and conservation organizations. In 2012, the legislature and governor empowered the Coastal Conservancy with a new authority (SB 1066, Lieu) to prepare for and adapt to the effects of climate change and take action against its causes. The Conservancy quickly responded with the launch of its Climate Ready Program and the first Climate Ready grant round. Through three competitive grant rounds, the Coastal Conservancy has awarded $7.3 million for 42 Climate Ready grants. The Crissy Field Sea Level Rise Analysis was funded under the third Climate Ready grant round in June 2015.

These programs, and this project, therefore fit within the State of California’s greater efforts to mitigate the causes and prepare for the effects of a changing climate. Executive Order B-30-15, which establishes the state’s greenhouse gas reduction goals of 80 percent below 1990 levels by 2050, also requires State agencies to take climate change into account in their planning and investment decisions. The Coastal Conservancy is a proud supporter of the Crissy Field Sea Level Rise Analysis. We recognize the importance of planning ahead for climate change impacts at our parks across the state, and commend the work of the National Park Service and the Golden Gate National Parks Conservancy in all of their efforts to prepare our parks for sea level rise.

Sincerely,

Sam Schuchat Executive Officer California State Coastal Conservancy

1.0 INTRODUCTION

THE PURPOSE OF THIS ANALYSIS IS TO UNDERSTAND HOW CRISSY FIELD WILL BE IMPACTED BY SEA LEVEL RISE BY APPLYING AND DOCUMENTING THE LATEST, MOST WIDELY ACCEPTED SCIENCE ON SEA LEVEL RISE. THIS CRISSY FIELD + SEA LEVEL

RISE-UP, COMMUNITY WORKSHOP + SEA LEVEL RISE ANALYSIS IDENTIFIES WHICH ADAPTATION OR PROTECTION MEASURES ARE AVAILABLE TO PROTECT AND ENHANCE THE CULTURAL, NATURAL RESOURCES AND EXISTING PARK ASSETS, AND WILL HELP GUIDE FUTURE IMPROVEMENTS AT CRISSY FIELD BY THE NATIONAL PARK SERVICE, BASED UPON SUBJECT MATTER EXPERTISE AND COMMUNITY INPUT.

PROJECT SUMMARY

LOCATED ALONG THE SAN FRANCISCO WATERFRONT, just inside the Golden Gate, Crissy Field is one of the most popular Bay Area recreation destinations for local residents and visitors alike. Fifteen years ago, through the generosity of the Evelyn and Walter Haas, Jr. Fund and Colleen and Robert Haas, as well as thousands of community volunteers and donors, the Golden Gate National Parks Conservancy and National Park Service restored the site from a derelict Army airfield to a national park, an effort that included recreating eighteen acres of tidal marsh, and twenty-two acres of beach, dune and dune swale habitat, a historic airfield, and recreational facilities at East Beach. Crissy Field has been much loved and well used since its reopening in 2001. The site now serves over one million visitors each year, and with the Presidio Parkway (Doyle Drive replacement) well underway and adjacent park access improvements now being planned that will reconnect the Presidio's Main Post to Crissy Field, future visitor use at Crissy Field is only expected to increase. The National Park Service and Golden Gate National Parks Conservancy are now exploring how best to meet the challenges and needs anticipated over the next decades at Crissy Field. As an integral part of this effort, due to the siteâ&#x20AC;&#x2122;s location at the edge of San Francisco Bay, a careful and thorough consideration of possible climate change scenarios is essential. The purpose of the CRISSY FIELD + SEA LEVEL RISE-UP, COMMUNITY WORKSHOP + SEA LEVEL RISE ANALYSIS is to understand how Crissy Field will be impacted by sea level rise, and what adaptation or protection measures are appropriate to protect and enhance the cultural, natural resources and existing park assets. Documenting the latest, most widely accepted science on sea level rise, National Park Service expertise and community input, this report will help guide future investments at Crissy Field. A Climate Ready grant from the California State Coastal Conservancy supported the CRISSY FIELD + SEA LEVEL RISE-UP.

GUIDING GOALS FOR THE ANALYSIS INCLUDED: SUMMARIZE the latest, most widely accepted science on sea level rise (SLR) and on potential effects of SLR in terms of inundation. Questions addressed include:

WHAT factors contribute to the sea level rise predictions described in the literature?

HOW will future data help guide planning and implementation?

COMPILE DATA on how sea level rise of 1, 2, 3 and 6 feet will affect San Francisco Bay at Crissy Field in order to illustrate what areas of the park are impacted.

ASSESS THE VULNERABILITY of existing conditions at Crissy Field including cultural and natural resources, infrastructure and park recreational areas.

SHARE the compiled data with the local community in a digestible and accessible way. Educate the community about SLR challenges and opportunities, and receive important feedback on which Crissy Field assets are most valued and why.

UNDERSTAND available adaptation strategies for Crissy Field. To that end, the team conducted a series of internal stakeholder workshops. Stakeholders included key players from the Parks Conservancy, National Park Service, and the Presidio Trust. The stakeholders provided a collective understanding of valued park assets, and how sea level rise analysis will guide future planning and implementation efforts.

An interactive workshop was held on January 30, 2016 at the Presidio, inviting the community to imagine a future for Crissy Field under different sea level rise scenarios. Stakeholders and community members learned about the science of climate change and sea level rise, and were able to view projections for sea level rise at Crissy Field. Participants then engaged in a hands-on activity overlaying various adaptation tools onto 3-foot or 6-foot sea level rise scenarios. Based on these goals and the team’s research and analysis, a series of adaptation strategies emerged that captured the stakeholders' and community’s values in response to sea level rise at Crissy Field.

IDENTIFY POTENTIAL ADAPTATION STRATEGIES THAT ARE APPROPRIATE FOR CRISSY FIELD. QUESTIONS ADDRESSED INCLUDE: WHAT ARE THE CHARACTERISTICS OF EACH STRATEGY,

The seven GAME OF TIDES gameboards generated at the workshop were further analyzed based on four adaptation strategies to demonstrate how informed input of professionals and community members could be used to generate future planning scenarios.

STRATEGIES INCLUDE: PROTECT: Protect the existing resource with both ‘hard’ or ‘soft’ design strategies.

RETREAT: Remove buildings or hard infrastructure, and replace with natural amenities like wetlands which are more resilient to sea level rise over time.

ADAPT: Adapt the asset (i.e. a building), to be resilient to sea

including physical requirements, infrastructure and environmental impacts, aesthetic characteristics, and recreation and access impacts?

level rise. Raise the finish floor elevation of the building to be above projected elevations for sea level rise. Adapt the first floor of the building to be floodable during extreme high tide events.

WHICH AREAS SHOULD BE PROTECTED OR ALLOWED TO

ACCESS: Provide pedestrian access in new locations as

uses, cultural values, and stakeholder input?

needed, to provide access to the cultural, recreational and natural assets of the park.

RETREAT based on vulnerability, existing and proposed land HOW CAN RISING SEA LEVELS ENHANCE natural, cultural, and recreational resources?

HOW CAN CRISSY FIELD ADAPT INCREMENTALLY over time to minimize coastal hazard risks and resource impacts, maximize protection of public access, recreation and sensitive coastal resources and serve as a demonstration site that increases public awareness of sea level rise impacts and climate-smart adaptation planning and implementation?

This CRISSY FIELD + SEA LEVEL RISE-UP report identifies what adaptation or protection measures are available to protect and enhance the cultural, natural resources and existing park assets, and will help guide future improvements at Crissy Field by the National Park Service, based upon subject matter expertise and community input.

2.0 SEA LEVEL RISE ANALYSIS FOR THIS CRISSY FIELD + SEA LEVEL RISE-UP REPORT, DATA AND RESEARCH WAS COLLECTED ON: SCIENCE OF SEA LEVEL RISE EXISTING PARK ASSETS TIDE ELEVATIONS AT 1, 2, 3 + 6 FEET OF SEA LEVEL RISE SEA LEVEL RISE + SHORELINE EROSION.

The National Park Service, California Ocean Protection Council, National Oceanic and Atmospheric Administration, National Research Council, Federal Emergency Management Administration, Golden Gate National Parks Conservancy and the Presidio Trust. Based on the data collected from these sources, analysis of the potential effects of sea level rise (SLR) was carried out in terms of inundation. (Inundation is defined as flooding due to static high tidal water levels, which persist for a long period of time, at least several hours.)

The effects of wave action and shoreline erosion have not been included in the inundation analysis. However, a qualitative discussion of the implications of SLR on shoreline erosion at Crissy Field is included. This qualitative discussion focuses on the natural response of the shoreline to SLR and the implications of wave runup and overtopping. These are important factors as they affect the accessibility and function of resources and assets and should be considered when assessing the vulnerability of Crissy Field to SLR.

SEA LEVEL RISE SCIENCE

Unlike the estimates of sea level change from thousands of years ago, modern rates of global sea level change can be estimated using tide gauge measurements, which are available dating back into the 17th century, and more recently, satellite altimetry measurements of sea-surface heights, which have been available for the past two decades. For global sea level change, satellite altimetry shows about a 50% higher rate of sea level change when compared to tide gauge estimates over the same timespan (e.g., Nerem et al., 2010).

300 250

CO2 (PPM)

400

GLOBAL TEMPERATURE

2 0 -2 -4

T ANOMALY (OC)

200

SEA LEVEL 0 -200 Chart Adapted from Hansen + Sato

400

-400 350

300

250

200

150

100

TIME (THOUSANDS OF YEARS BEFORE PRESENT)

Sediment and ice-cores provide a record of sea level, temperature and carbon dioxide (CO2) variation dating back thousands of years. Over this time scale, there were long periods of cold temperatures (glacial or ice ages) during which large continental ice sheets grew and sea levels lowered. These periods were followed by periods of warm temperatures (interglacial periods) during which the ice sheets would retreat and sea levels would rise. Similarly, during ice ages CO2 levels would fall and then rise again during interglacial periods. Since the end of the last ice age, CO2 levels have been rising and more notably since the start of the present geologic era, or the Holocene, have risen to levels above those historically documented.

SEA LEVEL (FT)

At the time of the last Glacial Maximum (~20,000 years ago), large quantities of sea water were stored as ice and covered much of North America, northern Europe, and parts of Asia. Sea levels were estimated to be approximately 410–440 feet lower than present (Peltier and Fairbanks, 2006; Clark et al., 2009). Since then, the melting of these ice sheets caused sea levels to rise at an average rate of about 0.4 in/yr (Alley et al., 2005). Modeling studies suggest that around 7,000 years ago the rate of ice melt dropped significantly and began to steadily decline to a value of near zero around 2,000 years ago (Gehrels, 2010, Fleming et al., 1998; Peltier, 2002b; Peltier et al., 2002). A period of relative stability followed, and then global sea levels began rising shortly after the beginning of the industrial era.

CO2 CONCENTRATION

LAST ICE AGE HOLOCENE

Intergovernmental Panel on Climate Change (IPCC) and the National Research Council (NRC), which is part of the National Academy of Sciences (NAS), provide a comprehensive discussion of past sea level variation and future projections which is summarized here. Rates of sea level changes vary significantly over time. Sediment and icecores provide a record of sea level variation dating back thousands of years and provide an understanding of the nature and causes of current and future sea level variation. Over this time scale, there were long periods of cold temperatures (glacial or ice ages) during which large continental ice sheets grew and sea levels lowered. These periods were followed by periods of warm temperatures (interglacial periods) during which the ice sheets would retreat and sea levels would rise. The Earth is presently in an interglacial period. Traces of ancient shorelines, found along many of the world’s coastlines, provide evidence that global mean sea level was at least 20 feet higher during the last interglacial period (~116,000–130,000 years ago) than at present (Kopp et al., 2009).

GLOBAL FLUCTUATIONS IN CO2, TEMPERATURE AND SEA LEVELS

EERIAN

SEA LEVEL RISE is a widely studied and evolving field of science. The

HISTORIC SEA LEVEL RISE

RECENT SEA LEVEL RISE

14 0

LAST GLACIAL MAXIMUM

SEA LEVEL CHANGE (IN)

SEA LEVEL CHANGE (FT)

-100

MELTWATER PULSE 1A

-200

-300

SATELLITE ALTIMETRY

3 YEAR AVERAGE

0 -400 -2 Chart adapted from Robert A. Rohde

Graphic adapted from Bruce Douglas

-500 22

1880

1900

1920

1940

1960

1980

2000

TIME (THOUSANDS OF YEARS BEFORE PRESENT)

At the time of the last Glacial Maximum (~20,000 years ago), ice sheets and glaciers covered much of North America, northern Europe, and parts of Asia. Sea levels were estimated to be approximately 410 feet -430 feet lower than present (Peltier and Fairbanks, 2006; Clark et al., 2009) during this time. Since then, the melting of these ice sheets (Peltier and Fairbanks, 2006) caused sea level to rise at an average rate of about 0.4 in/yr (Alley et al., 2005) with periods of rapid acceleration during which time sea levels rose at a rate of 1.2 â&#x20AC;&#x201C; 2.4 in/year, as indicated by Meltwater Pulse 1A. Modeling studies by Gehrels (2010) suggest that around 7,000 years ago the rate of ice melt dropped significantly and began to steadily decline to a value of near zero around 2,000 years ago (Fleming et al., 1998; Peltier, 2002b; Peltier et al., 2002).

Global sea levels began rising shortly after the beginning of the industrial era, based on recent sea level data gathered from 23 tide gauges. More recently, within the past two decades, satellite altimetry has been used to track changes in global sea level. The sea level variation observed in the short-term data from satellite altimetry shows about a 50% higher rate of sea level change when compared to the longer-term tide gauge measurements. The observed sea level variation at Golden Gate Bridge indicates a rise of 8 (based on gauges) to 12 (based on satellite altimetry) inches per century.

NRC 2012 PROJECTION RANGE

SEA LEVEL RISE PROJECTIONS 6

Typically, projections of global sea level rise are based on THERMAL EXPANSION OF SEA WATER (due to warming of the oceans) and LAND BASED ICE LOSS (glaciers, ice caps, ice sheets). To assess true impacts at a location such as Crissy Field, there are additional contributing factors that include TERRESTRIAL WATER STORAGE (ground water depletion and surface water impoundment), LOCAL LAND MOVEMENT and WIND DRIVEN DYNAMIC OCEAN HEIGHTS.

5.5' INCREASE FROM 2000 LEVELS (FT)

The Presidio tide gauge has been recording water level elevations since 1897. Sea level rise trends for this gauge from NOAA indicate an annualized sea level change rate of approximately 2 mm/year or approximately 8 inches/century. There are no continuous satellite measurements for this area, so data showing higher rates of SLR observed more recently at other locations are lacking for San Francisco Bay.

(HIGH RANGE)

SATELLITE ALTIMETRY DATA

HISTORIC TREND (NO ACCELERATION)

3' (NRC PROJECTION)

2 1.4'

The thermal expansion of sea water and local land movement components of sea level rise have been topics of considerable research and modeling by organizations such as the NRC, the US Environmental Protection Agency, the IPCC, etc. for some time. The effect of land based ice loss on sea level rise is a relatively new area of study and can be an even larger contributing factor to future changes in sea levels. New research results indicate that the relative contribution of land ice to global sea-level rise is increasing and that the ice loss rate from the Greenland Ice Sheet has increased since 1993 due to increasing surface melt of the Greenland Ice Sheet and faster flow of some outlet glaciers in both Greenland and Antarctica (NRC 2012). The possibility of increased ice sheet melting of the Greenland and Antarctic ice sheets is important to future sea level rise because they store the equivalent of at least 213 ft of sea level. Recently, global projections of sea level rise for 2050 and 2100 have been produced by the IPCC, NRC and others based on semi-empirical models and General Circulation Models that use assumed future emission scenarios. These projections are summarized in the graphic chart and show the wide range of possible changes in sea level.

(LOWER RANGE)

0 1990

2000

IPCC PROJECTION RANGE HIGH RANGES LOW RANGES

2010

2020

2030

2040

CCCC PROJECTION RANGE HIGH RANGES - NO DAM CORRECTIONS LOW RANGES - CORRECTED FOR DAMS

2050

2060

RAHMSTOF PROJECTION RANGE HIGH RANGE LOW RANGE

2070

2080

2090

NRC PROJECTION RANGE FULL PROJECTION RANGE PROJECTION

HIGH RANGE LOW RANGE

2100

2110

NOTE: CURVES HAVE BEEN DEVELOPED BASED ON VALUES PROVIDED AT 2050 AND 2100, CURVE SHAPES ARE APPROXIMATE

Recently, global projections of sea level rise for 2050 and 2100 have been developed by the Intergovernmental Panel on Climate Change (IPCC) and others (Rahmstorf et al.) using semiempirical models and General Circulation Models that use assumed future emission scenarios. In addition, the National Research Council (NRC) and the California Climate Change Center (CCCC) have developed projections specific to California. These projections are summarized in the chart above, including historic rates of sea level rise projected into the future, the most recent projections for 2100 by the National Research Council for the San Francisco Area, and observed water levels from satellite altimetry. The NRC 2012 values are widely considered to be the best available science on sea level rise for the San Francisco Bay Area.

ICE SHEET MELT IN GREENLAND For the state of California, Governor Schwarzenegger issued Executive order S-13-08 in 2008 which asked the NRC to assess sea level rise in order to assist state agencies in planning for adaptation. The study, “Sea-Level Rise for the Coasts of California, Oregon, and Washington: Past Present and Future”, which was released in March 2013, has been adopted by the state and several regulatory agencies as the best available science on sea level rise for California.

1992

The NRC Report includes discussion of historic sea level observations, projections of high, low and likely sea level rise for 2030, 2050 and 2100, and considers local conditions along the California, Oregon, and Washington coast. The NRC Report provides regional estimates of relative sea level rise for the west coast which include the sum of contributions from the thermal expansion of seawater, wind driven dynamic ocean heights, land based ice loss and vertical land motion.

2002

Map adopted from Arctic Climate Impact Assessment

Extent of ice melt on the Greenland Ice Sheet in 1992 and 2002. The extent of the seasonal melt zone, where summer warmth turns snow and ice around the edges of the ice sheet into slush and ponds of meltwater, has been expanding inland and to record high elevations in recent years. Ice sheet melt of the Greenland Ice Sheet and Antarctic Ice Sheet represents up to 23 feet and 187 feet of potential sea level, respectively.

NRC REPORTS FOR SEA LEVEL RISE ESTIMATES FOR SAN FRANCISCO

The table on this page presents the estimates of sea level rise developed by the NRC specifically for the region that includes San Francisco Bay. It includes “Projections” of SLR (for example, 36 ± 10 inches in 2100) which represent the most likely SLR values based on a moderate level of greenhouse gas emissions and extrapolation of continued accelerating land ice melt patterns, plus or minus 1 standard deviation as well as the “Range” of SLR values. The limits of the Range (for example, 17 and 66 inches for 2100) represent unlikely but possible levels of SLR using both very low and very high emissions scenarios and, at the high end, including significant land ice melt that is currently not foreseen but could occur. Major sources of uncertainty in global and regional projections are related to assumptions about future ice losses, an incomplete understanding of the global climate system, the inability of global climate models to accurately represent all important components of the climate system at global or regional scales, the assumed constant rate of vertical land motion over time and the need to make assumptions about future conditions (e.g., greenhouse gas emissions, large volcanic eruptions). Continued research into these fields will inform future refinements to future sea level rise projections and help understand the impacts of sea level rise more fully.

MAPPING EXISTING ASSETS

THE FOLLOWING FIVE MAPS ILLUSTRATE THE ASSETS + RESOURCES PRESENT AT CRISSY FIELD, WHICH WILL BE AFFECTED WHEN SEA LEVELS RISE. THE ASSETS ARE CATEGORIZED IN THE FOLLOWING WAY: EXISTING CONDITIONS + ORIENTATION MAP HISTORIC, ARCHAEOLOGICAL + CULTURAL RESOURCES NATURAL RESOURCES VIEWS, PUBLIC ACCESS + RECREATION PUBLIC INFRASTRUCTURE + UTILITIES

EXISTING CONDITIONS This map identifies place names, streets and familiar areas at Crissy Field to orient stakeholders.

OLD FORT POINT

+ FFE 15

WEST BLUFF PICNIC AREAS

CRISSY FIELD PROMENADE

NEW PRESIDIO PARKLANDS

MARSH

EAST BEACH

TEMPORARY CRISSY FIELD CENTER + BEACH HUT

ST. FRANCIS YACHT CLUB AND MARINA

MARINA GREEN

OLD FORT POINT NATIONAL HISTORIC SITE

MAR

INE

DRIV

TORPEDO WHARF

FFE 14

FFE 12

9 86

985 /9

WARMING HUT

FFE 14 988 E 12 983 FF

NATIONAL PARK SERVICE: AREA A

FUTURE LONG AVENUE ACCESSIBLE CONNECTION

CITY OF SAN FRANCISCO

WEST BLUFF GREATER FARALLONES NATIONAL MARINE SANCTUARY CAMPUS

+ FFE 12

+ FFE 12.5

937 935

FFE 11.5

FFE 12

933

934

FUTURE SPORTS BASEMENT AND PARKING LOT

+ FFE 12.5

TEMPORARY CRISSY FIELD CENTER

+ FFE 10.5

FFE 12.5

+ FFE 12

ST. FRANCIS YACHT CLUB

GOLDEN GATE YACHT CLUB

926

924

CRISSY BEACH

+ FFE 13

DUNES FFE 13

+920 65

+ FFE 16 + FFE 15 650

649

643

VEHICULAR CIRCULATION FINISH FLOOR ELEVATION

603 + FFE 13.0

641 640 + FFE 12

E + FFE

+ FFE 11.5

MARINA GREEN MARINA BOULEVARD

+ FFE 12 + 632

1185

1186

1187

1184 + FFE 12.5

1183

1182

1188

FFE 12.5

FFE 13.0

610

ELL A VENU McDO W

PRESIDIO TRUST: AREA B

EAST BEACH

MASON DRIVE

644

+ FFE 12

+ FFE 13.5

MARSH

AIRFIELD FFE 16

DUNES

PROMENADE

+ FFE 12.5

631

PRESIDIO DOYLE DRIVE IMPROVEMENTS STABLES PARKING AREA

MARINA DISTRICT

MAIN POST FUTURE PRESIDIO PARKLANDS

FUTURE QUARTERMASTER REACH

PALACE OF FINE ARTS THEATER FUTURE PARKING LOT

0’

200’

400’

800’

1200’

HISTORIC, ARCHAEOLOGICAL + CULTURAL RESOURCES Historic buildings such at Old Fort Point are identified in red. Cultural resources such as the historic airfield are pointed out. ARCHAEOLOGICAL ASSETS ARE AFFECTED BY SEA LEVEL RISE, HOWEVER LOCATIONS OF THE

ASSETS ARE CONFIDENTIAL AND ARE NOT SHOWN ON THE MAP.

OLD FORT POINT

TORPEDO WHARF

AIRFIELD AND VIEW TO GOLDEN GATE BRIDGE

AIRFIELD

HISTORIC SEAPLANE RAMP

AIRFIELD

HISTORIC HANGERS

BRIDGE PYLON OLD FORT POINT ORIGINAL SEAWALL OLD FORT POINT NATIONAL HISTORIC SITE COUNTERSCARP GALLERY FOUNDATION MONTEREY CYPRESS CONNECTION LIGHTHOUSE RESIDENCE MARINE DRIVE DITCH

TORPEDO WHARF

989 987 988

985 986 983

CABLE HUT HISTORIC SEAPLANE RAMP HISTORIC AIRFIELD

HISTORIC RACE TRACK FOOTPRINT

1905

937

1906

935

1902 1901

933 934

1903

EUCALYPTUS WINDROW

1907

926

920 65

1 650

NPS 6

603

640 641 ,

1185 1184

1186 1183

1187 1182

1188

632 631

HISTORIC BUILDING NON-HISTORIC BUILDING

0’

200’

400’

800’

1200’

NATURAL RESOURCES Natural resource areas of the park such at Snowy Plover Wildlife Protection Area and the intertidal levels of the marsh will be affected by sea level rise.

17 16 18

13 9

WILDLIFE PROTECTION AREA - SNOWY PLOVER WILDLIFE PROTECTION AREA - SNOWY PLOVER WILDLIFE PROTECTION AREA

MARSH

MARSH OUTLET

BEACH DUNES

QUARTERMASTER REACH

MARINE DRIVE STORM DRAIN CHANNEL HABITAT FOR SF FORK-TAILED DAMSELFLY ROCKY INTERTIDAL ZONE

989

988

DUNE SCRUB ELEVATION 8.5 NAVD 88

WILDLIFE PROTECTION AREA SNOWY PLOVER MARINE MAMMALS / SHOREBIRDS ON SANDY BEACH IN WILDLIFE PROTECTION AREA

985 /9

983

WILDLIFE PROTECTION AREA MARSH PLANT HABITAT BIRD HABITAT FISH HABITAT

VEGETATED INTERTIDAL AND HIGH MARSH TRANSITION ELEVATION 4.5 NAVD 88 SANDY SHOALS: POTENTIALLY EXPOSED TO LOW TIDES ELEVATION 3 - 4.5 NAVD 88

PRESIDIO TIDE GAUGE ON COAST GUARD PIER

SANDY BEACH COASTAL DUNES MARSH CHANNEL

937

OPEN WATER / SANDY SHOALS / SUBTIDAL ELEVATION 3 NAVD 88

935 933 934 926

DUNE SWALE

924

920

651 650 649

644 643 603

641 640

1185

1186

1187

1184

1183

1182

1188

610 632 631

FUTURE QUARTERMASTER REACH

0’

200’

400’

800’

1200’

VIEWS, PUBLIC ACCESS + RECREATION Park access and recreation areas such as the beach, the east beach parking area, and the promenade will be affected as sea levels rise.

PROMENADE

AIRFIELD

GOLDEN GATE OVERLOOK AT CRISSY FIELD

OLD FORT POINT NATIONAL HISTORIC SITE OLD FORT POINT BATHROOMS

WEST BLUFF

TIDAL MARSH BIRD WATCHING

WARMING HUT

EAST BEACH KITE BOARDING

EAST BEACH

FUTURE LONG AVENUE ACCESSIBLE CONNECTION BATHROOMS WARMING HUT TORPEDO WHARF

GOLDEN GATE OVERLOOK AT CRISSY FIELD

AMPHITHEATER WEST BLUFF PICNIC AREAS WEDDINGS MARATHON STARTING POINT LA PETITE BALEEN SWIM SCHOOL ROARING MOUSE CYCLES BIKE REPAIR HOUSE OF AIR TRAMPOLINE PARK

989 86 985 /9 988

DOG WALKING ON LAWN

983

SPORTS BASEMENT BIKE RENTALS FITNESS CLASSES COMMUNITY SPACE GROUP RUNS, RIDES, AND EVENTS NEW PRESIDIO PARKLANDS GARDENS OVERLOOKS LEARNING LANDSCAPE NEW PARKING AREAS EXPANDED CRISSY FIELD CENTER CAMPUS

GREATER FARALLONES NATIONAL MARINE SANCTUARY VISITOR CENTER PROMENADE ACCESS PATHS

1905

937

FORT POINT BREWING COMPANY

1906 1902

935

1901

933

PROMENADE / SAN FRANCISCO BAY TRAIL

926

ST. FRANCIS YACHT CLUB MARINA

WAVE ORGAN GOLDEN GATE YACHT CLUB

EAST BEACH BATHROOMS EAST BEACH PARKING LOT BEACH ACCESSIBLE ENTRY

CYPRESS GROVE

1903 1907

934

EAST BEACH PICNIC AREAS EAST BEACH BOARD SAILING KITE BOARDING FAMILY PLAY

CRISSY FIELD CENTER

MARINA GREEN SAN FRANCISCO BAY TRAIL

EAST BEACH ENTRY

924

920

651 650 649

644 643

603 641+ 640

1185

1186

1187

1184

1183

1182

1188

610 632 631

USF PRESIDIO BUILDING PLANET GRANITE CLIMBING GYM

BEACH HUT & TEMPORARY CRISSY FIELD CENTER ENTRY CYPRESS GROVE

0’

200’

400’

800’

1200’

PUBLIC INFRASTRUCTURE + UTILITIES As sea levels rise, high tide events will back up into existing storm drains and flood areas at low drain inlets.

OLD FORT POINT

OLD FORT POINT STORM DRAIN CHANNEL

EAST BEACH SEATWALL

WEST BLUFF SEAWALL

EAST BEACH SEATWALL AND EXPOSED K-RAIL

IMPROVED OUTLET GULF FARALLONES

MARSH OUTFALL

MARSH

MARSH OUTLET AT EAST BEACH

CONCRETE CURB AND DRAIN CHANNEL MARINE DRIVE CULVERT MARINE DRIVE SEAWALL MARINE DRIVE STORM DRAIN CHANNEL MARINE DRIVE CULVERT

OUTFALL ELEVATION 8.68 NAVD 88 OUTFALL ELEVATION 8.67 NAVD 88

MAR

INE

DRIV

SEAWALL RIPRAP SD PIPE AND MANHOLE

985 /9 989 988

SD PIPE INV OUT ELEVATION 5.85 NAVD 88

983

WEST BLUFF PARKING LOT

E OUTFALL (BURIED AND CLOSED)

RIPRAP WALL ELEVATION 12 NAVD 88

D OUTFALL TO MARSH

OFFSHORE MONITORING WELL

C MARSH CHANNEL

A OUTFALL

IJKL SD PIPE INV OUT -1.30 (RECENTLY RENOVATED AS PART OF THE GULF OF FARALLONES IMPROVEMENTS)

ARMORED SHORELINE G OUTFALL TO MARSH

PRESIDIO TIDE GAUGE ON COAST GUARD PIER 937

1905/ 1906 1902

935

MASON STREET

RIPRAP

1901

933

1903 1907

934

B OUTFALLS ELEVATION 7.57 NAVD 88 BURIED AND PLUGGED EAST BEACH PARKING LOT

F OUTFALL TO MARSH

926

ELECTRICAL SWITCH

ST. FRANCIS YACHT CLUB PARKING LOT

924

PROMENADE

920

651 650 649

644

643 603 641 640

1185

1186

1187

1184

1183

1182

1188

610 632 631

SEWER PUMP STATION OR OUTFALL RIPRAP OR SEAWALL ARMORED SHORELINE ELECTRICAL SWITCH

SPS - SEWER PUMP STATION STABLES PARKING AREA

FUTURE QUARTERMASTER REACH CONNECTION

DOYLE DRIVE INTERSECTION FUTURE PARKING LOT FUTURE SPORTS BASEMENT PARKING LOT

0’

200’

400’

800’

1200’

MAPPING SEA LEVEL RISE

TIDES OF GOLDEN GATE (JAN - FEB 1998)

High water levels used in the vulnerability analysis of Crissy Field cover a range of tides. They represent water levels that occur frequently (Mean Higher High Water), those that occur a few times a year (King Tides) and those that have a low probability of occurrence each year (1% chance of occurrence or 100-year return period high tide). The tidal elevations are based on observations made at the long term National Oceanic and Atmospheric Administration tide gauge (# 9414290) in San Francisco, CA. This gauge has been recording tidal water levels since 1897, providing a long term time series of observations appropriate for estimating the three high water elevations considered. Each of these elevations are defined below:

KING MHHW MHW MSL MLW MLLW

MEAN HIGHER HIGH WATER (MHHW): The average of the higher

KING TIDE

7.0

high water elevation of each tidal day, observed over a 19-year period called the National Tidal Datum Epoch.

MEAN HIGHER HIGH WATER (MHHW)

5.4

KING TIDE: A colloquial term for an especially high tide occurring

MEAN HIGH WATER (MHW)

5.2

only a few times a year, typically when the gravitational pull of the sun and the moon are in alignment.

MEAN SEA LEVEL (MSL)

3.1

MEAN LOW WATER (MLW)

1.1

MEAN LOWER LOW WATER (MLLW)

0.0

100-YEAR HIGH TIDE EVENT: A tidal elevation that statistically has a 1-percent chance of occurring in any given year.

7 6

4 3 2

TIDE (FT)

1 0 -1 -2

TIDE

TIDAL RANGE (FEET)

The tidal elevations were combined with 4 different sea level rise scenarios. The sea level rise scenarios used in the inundation mapping cover the range of estimates provided by the NRC study for the coasts of California, Oregon and Washington. By using 1, 2, 3, and 6 feet of sea level rise, the inundation maps allow for the assessment of exposure in the near future, as well as long-term under the likely and the unlikely-but-possible sea level rise estimates for San Francisco Bay.

MHHW KING TIDE

These elevations were chosen because, based on function or land uses, various assets and resources have varying tolerances to the frequency of inundation. For example, residential or commercial buildings have a low tolerance for inundation by even infrequent events (i.e. the 100year tide). Public amenities such as the promenade can tolerate inundation during a 100-year tide event, but has a lower tolerance for inundation during more frequent events (i.e. king tides or high tides).

CURRENT TIDE LEVELS

100 YR TIDE

SEA LEVEL RISE MATRIX

+1 FT SEA LEVEL RISE

+2 FT SEA LEVEL RISE

+3 FT SEA LEVEL RISE

+6FT SEA LEVEL RISE

Mean Higher High Water (MHHW): The average of the higher high water elevation of each tidal day, observed over a 19-year period called the National Tidal Datum Epoch.

King Tide: A colloquial term for an especially high tide occurring only a few times a year, typically when the gravitational pull of the sun and the moon are in alignment.

This matrix shows the mapping of Sea Level Rise at Crissy Field at four different Sea Level Rise scenarios and three tidal elevations. 100-year High Tide Event: A tidal elevation that statistically has a 1-percent chance of occurring in any given year. 24

SHORELINE EROSION Coastal processes such as wave runup and overtopping, shoreline erosion, and beach and dune erosion shape the form of the Crissy Field shoreline. While the potential effects to Crissy Field due to combined tidal inundation and sea level rise is the primary focus of this analysis, an understanding of how the shoreline responds to increases in sea level is a valuable part of understanding its vulnerability. The coastal processes which impact the shoreline of Crissy Field are driven by swell wave action from the Pacific Ocean, wind waves developed over the San Francisco Bay, and strong tidal currents. Swell waves propagating through the Golden Gate from the Pacific Ocean are reduced in wave height due to wave transformation processes through the Golden Gate, but western portions of Crissy Field can experience swell waves up to 6 feet in height, with wave heights reducing in size further to the east. Wind waves generated by winter storms can generate extreme waves up to 3 feet in height along most portions of Crissy Field. The swell and wind waves drive sediment transport along the Crissy Field shoreline, as well as cause wave runup and overtopping along the revetment and seawall protected portions of shoreline. Sediment transport along Crissy Field is also driven by the tidal fluctuation and resulting tidal currents, which primarily run parallel to shore. Increases in sea levels will alter the coastal processes that shape the shoreline of Crissy Field. Natural shorelines such as beaches, dunes and marshes evolve in response to increases in sea levels while hardened shorelines such as sea walls and revetments are static and remain unchanged by sea level rise, but allow for increased wave runup and overtopping which make them less effective in providing their intended protection. Large increases in sea levels result in larger recession. This recession would make portions of the beach, which are presently narrow potentially inaccessible and damage the promenade.

EAST BEACH EROSION SECTION CUT

SEA LEVEL RISE SECTIONS EAST BEACH EROSION SECTION

BEACH

MHHW

BEACH

+1' SLR

BEACH

+2' SLR

BEACH

+3' SLR

BEACH

+6' SLR

SEA LEVEL RISE SECTIONS DUNE EROSION SECTION

BEACH + DUNE

Natural shorelines such as beaches, dunes and marshes evolve in response to increases in sea levels while hardened shorelines such as sea walls and revetments are static allowing for increased wave runup and overtopping.

MHHW

+1' SLR

BEACH + DUNE

+2' SLR

BEACH + DUNE

+3' SLR

BEACH + DUNE

+6' SLR

Natural shorelines evolve in different ways in response to sea level rise. For beaches, increase in water depth caused by sea level rise allows for larger and more frequent wave action on the beach. This causes the beach to recede landward. Large increases in sea levels result in larger recession. This recession would make portions of the beach which are presently narrow potentially inaccessible and damage the promenade. For dunes, sea level rise increases the likelihood of erosion during storm events by reducing the beach width that provides protection from wave action. Over time the recession of the beach allows for wave action to directly impact the dunes resulting in erosion and loss of dune. Additionally, the primary source of sediment for natural dune growth and replenishment is typically the dry beach which fronts them. As sea levels increase and the beach recedes, reducing the dry beach area in front of the dunes, the sediment available for dune growth and replenishment through natural processes is reduced. Marshes respond differently than the other natural shorelines of Crissy Field. As sea levels rise, marshes have the potential to adapt naturally by migrating inland or aggrading to a higher elevation. For a marsh to migrate, flat slopes must extend up to higher elevations providing space and opportunity for the upland areas to transition as sea levels rise. For a marsh to aggrade, or increase its elevation, to match the increase in sea level, sufficient sediment and nutrients must be present in the water. In locations where slopes and area are not conducive to marsh migration, or sediment and nutrient supply is not high enough to keep pace with sea level rise, sea levels will inundate the marsh, eventually converting it to mud flat or subtidal habitat. For dunes, sea level rise increases the likelihood of erosion during storm events by reducing the beach width that provides protection from wave action. Over time the recession of the beach allows for wave action to directly impact the dunes resulting in erosion and loss of dune. DUNE EROSION SECTION CUT

WAVE RUNUP

MARINE DRIVE

Hardened shorelines at Crissy Field include revetments and seawalls fronting roadways (e.g. Marine Drive) and small portions of the beach armoring at East Beach. These hardened shorelines do not respond to sea level rise; as sea levels increase, the size and frequency of wave action on them increases, due to the increased depths offshore. This wave action acts higher up on the hardened shoreline which leads to increased wave runup and overtopping of the revetment or seawall. This overtopping is periodic and temporary and represents nuisance flooding of the landward side of the hardened shoreline.

Marine Drive presently experiences minor overtopping by wave action due to wave runup on the revetment and seawall. With future increases in sea level, this overtopping will increase in volume and frequency increasing the temporary inaccessibility of Marine Drive over time. This overtopping is often referred to as nuisance flooding due to the shorter duration and volume compared to inundation. Due to the immediate adjacency of Marine Drive to San Francisco Bay this could be a significant factor in the vulnerability of the road. MARINE DRIVE SECTION CUT

EAST BEACH The east beach revetment acts to stabilize the shoreline and prevents the shoreline from receding, due to wave action. Increases in sea level will result in increased levels of wave action and higher levels of wave runup and potential overtopping of the revetment, due to increases in offshore water depths. This reduces the usable width of beach landward of the revetment available for recreational use and increases the potential for erosion of the beach, leading to the potential failure of the revetment. EAST BEACH SECTION CUT

MARINE DRIVE SECTION 30

11’ VERTICAL WAVE RUNUP

MHHW 6’ TIDAL RANGE

EXISTING GRADE

EXISTING HILL

MARINE DRIVE

SEA WALL

RIP RAP

EAST BEACH SECTION

5’ VERTICAL WAVE RUNUP

MHHW + 3’ MHHW 6’ TIDAL RANGE

EXISTING GRADE 100

BEACH

3.0 VULNERABILITY ANALYSIS + RISK ASSESSMENT THE VULNERABILITY OF AN ASSET OR RESOURCE TO SEA LEVEL RISE AT CRISSY FIELD CAN BE ASSESSED BY EVALUATING THE EXPOSURE, SENSITIVITY + ADAPTIVE CAPACITY OF EACH ASSET OR RESOURCE. THESE TERMS ARE DEFINED BELOW:

EXPOSURE: the degree to which an asset or resource is susceptible to sea level rise. The exposure of various assets and resources under different combinations of tides and sea level rise is provided in the sea level rise matrix maps. These maps provide a visual representation of the exposure of Crissy Field to tidal inundation based on existing site grades taking into consideration sea level rise.

SENSITIVITY: the degree to which the function of an asset or resource would be impaired (i.e. weakened, compromised, or damaged) by sea level rise. Sensitivity is determined by evaluating the degree to which an asset or resource is affected by temporary (lasting several hours) inundation (i.e. does temporary inundation result in temporary interruption of the resource’s function or complete loss of the asset or resource). The sensitivity may vary for an asset or resource based on the frequency of in inundation.

ADAPTIVE CAPACITY: the asset’s inherent ability to adjust to sea level rise impacts without the need for significant intervention or modification. The asset or resource does not need to look the same as before the impact, but should provide similar functionality as it did prior to the impact.

VULNERABILITY ANALYSIS

As this is a subjective analysis, those assessing each asset or resource should be familiar with the function and use of the asset or resource. When assessing the vulnerability of an asset or resource it is important to take into consideration how that resource may be affected by shoreline erosion and wave runup and overtopping as these conditions can influence the exposure, sensitivity and adaptive capacity of an asset or resource in ways not shown on the inundation maps.

While the vulnerability assessment was performed to identify impacts from sea level rise, a risk assessment was performed to evaluate the magnitude of these impacts and likelihood of occurrence. The risk assessment was performed qualitatively for the four general categories of assets and resources.

THE FOLLOWING VULNERABILITY ANALYSIS MAPS ILLUSTRATE

ASSETS AFFECTED AT EACH LEVEL OF SLR. EACH OF THE FOLLOWING FIFTEEN MAPS SHOW THE LEVEL OF THE SEA AT EACH TIDAL ELEVATION. NOTES POINT TO AND DESCRIBE HOW AN ASSET IS AFFECTED AT EACH WATER LEVEL.

ELEVATION 6 (NAVD 88)

MAR

INE

DRIV

VULNERABILITY ANALYSIS CURRENT MHHW

TORPEDO WHARF

NO VULNERABLE ASSETS AT CURRENT MEAN HIGHER HIGH WATER

CRISSY BEACH PROMENADE AIRFIELD

MARSH

EAST BEACH

MASON STREET

PRESIDIO

MAIN POST

MHHW = MEAN HIGHER HIGH WATER = The average of the higher high water height of each tidal day observed over the standard 19 year observation period.

MHHW FREQUENCY = 50 times per year MHHW DURATION = 2.2 hours per event 32

ELEVATION 7 (NAVD 88)

VULNERABILITY ANALYSIS CURRENT KING TIDE

MAR

INE

DRIV

TORPEDO WHARF

INTERTIDAL ZONE IS TEMPORARILY COMPROMISED ON THE PROMENADE SIDE OF THE MARSH.

CRISSY BEACH PROMENADE AIRFIELD

MARSH MASON STREET

PRESIDIO

MAIN POST

KING TIDE = A colloquial term for an especially high tide above a certain elevation. It refers to a combined effect of lunar and solar alignment on the same side of earth, including other effects such as storms. In the context of Crissy Field, once a tide surpasses Elevation 7, it is considered a King Tide.

KING TIDE FREQUENCY = 6-8 times per year KING TIDE DURATION = 1.5 hours per event

EAST BEACH

ELEVATION 9 (NAVD 88)

VULNERABILITY ANALYSIS CURRENT 100YR TIDE

WAVES BREAK HIGH ON THE SEAWALL.

MAR

INE

DRIV

TORPEDO WHARF

MARSH TIDES ARE CLOSE TO OVERFLOWING AT MASON STREET.

EXPOSED + HIGH TIDES REACH SEATWALL.

PINCH POINT AT EAST BEACH BECOMES MORE NARROW.

CRISSY BEACH PROMENADE AIRFIELD

MARSH

EAST BEACH

MASON STREET

PRESIDIO

MAIN POST

100YR TIDE EVENT = A flood height that statistically has a 1-percent chance of occurring in any given year.

100YR TIDE EVENT FREQUENCY = statistically, once every 100 years 100YR TIDE EVENT DURATION = 2 hours per event

K-RAIL

ELEVATION 7 (NAVD 88)

VULNERABILITY ANALYSIS 1 FT SLR ABOVE CURRENT MHHW

MAR

INE

DRIV

TORPEDO WHARF

BEACH PINCH POINT BECOMES MORE NARROW AND BEACH RETREATS TOWARDS DUNES.

MARSH INTERTIDAL ZONE BEGINS TO NARROW. SUBTIDAL ZONE INCREASES.

EAST BEACH PINCH POINT BECOMES MORE NARROW. BEACH WILL RETREAT TOWARDS PROMENADE.

CRISSY BEACH PROMENADE MARSH

AIRFIELD

EAST BEACH

MASON STREET

PRESIDIO

MHHW = MEAN HIGHER HIGH WATER = The average of the higher high water height of each tidal day observed over the standard 19 year observation period.

MHHW FREQUENCY = 50 times per year MHHW DURATION = 2.2 hours per event

MAIN POST BEACH RETREAT TOWARDS DUNES

INTERTIDAL ZONE

ELEVATION 8 (NAVD 88)

MAR

INE

DRIV

VULNERABILITY ANALYSIS 1 FT SLR ABOVE CURRENT KING TIDE

TORPEDO WHARF

BEACH RETREATS TOWARD DUNES.

HIGH TIDES COMPROMISE THE SEATWALL FOUNDATION.

TEMPORARY INUNDATION OF INTERTIDAL ZONE.

CRISSY BEACH PROMENADE AIRFIELD

MARSH

EAST BEACH

MASON STREET

PRESIDIO

MAIN POST

East beach flood

KING TIDE FREQUENCY = 6-8 times per year KING TIDE DURATION = 1.5 hours per event 36

VULNERABILITY ANALYSIS 1 FT SLR ABOVE CURRENT 100 YR TIDE

ELEVATION 10 (NAVD 88)

WAVES BREAK HIGH ON THE SEAWALL AND SPILL OVER WALL.

MAR

INE

DRIV

TORPEDO WHARF

WAVES BREACH SEAWALL. WILDLIFE PROTECTION AREA TEMPORARILY INUNDATED.

DUNES UNDER WATER FROM HIGH TIDE. POSSIBLE SAND DEPOSITION ON THE PROMENADE.

PARKING AT THE GREATER FARALLONES NATIONAL MARINE SANCTUARY CAMPUS UNDER WATER. OVERLOOK UNDER WATER. TEMPORARY LOSS OF INTERTIDAL ZONE.

PROMENADE UNDER WATER. MASON STREET STORM DRAINS BEGIN TO BUBBLE UP FROM HIGH TIDE.

BEACH ACCESS TEMPORARILY LOST.

CRISSY BEACH PROMENADE AIRFIELD

MARSH MASON STREET

PRESIDIO

100YR TIDE EVENT = A flood height that statistically has a 1-percent chance of occurring in any given year.

100YR TIDE EVENT FREQUENCY = statistically, once every 100 years

100YR TIDE EVENT DURATION = 2 hours per event

MAIN POST

EAST BEACH

ELEVATION 8 (NAVD 88)

MAR

INE

DRIV

VULNERABILITY ANALYSIS 2 FT SLR ABOVE CURRENT MHHW

TORPEDO WHARF

BEACH RETREATS TOWARDS DUNES. DUNES BECOME MORE NARROW AND SHORTER.

MAJORITY OF INTERTIDAL ZONE LOST ON A DAILY BASIS.

BEACH WILL RETREAT TOWARDS PROMENADE. ANGLE OF BEACH WILL BECOME MORE SHALLOW. SEATWALL FOUNDATION POSSIBLY EXPOSED.

CRISSY BEACH PROMENADE AIRFIELD

MARSH

EAST BEACH

MASON STREET

PRESIDIO

MAIN POST

MHHW = MEAN HIGHER HIGH WATER = The average of the higher high water height of each tidal day observed over the standard 19 year observation period.

MHHW FREQUENCY = 50 times per year MHHW DURATION = 2.2 hours per event 38

ELEVATION 9 (NAVD 88)

VULNERABILITY ANALYSIS 2 FT SLR ABOVE CURRENT KING TIDE

MAR

INE

DRIV

TORPEDO WHARF

MARSH TEMPORARILY FILLS AND BECOMES SUBTIDAL.

WATER LEVEL COMES CLOSE TO THE OVERLOOK ELEVATION

SEATWALL FOUNDATION POSSIBLY EXPOSED RIP RAP WALL BREACHED

CRISSY BEACH PROMENADE AIRFIELD

MARSH MASON STREET

PRESIDIO

KING TIDE FREQUENCY = 6-8 times per year KING TIDE DURATION = 1.5 hours per event

MAIN POST

EAST BEACH

ELEVATION 8 (NAVD 88)

VULNERABILITY ANALYSIS 2 FT SLR ABOVE CURRENT 100 YR TIDE

HIGHER PROBABILITY OF WAVES CRASHING OVER THE SEAWALL

MAR

INE

DRIV

HALLECK STREET TEMPORARILY BLOCKED.

TORPEDO WHARF

WAVES BREACH SEAWALL, PROMENADE AND WEST BLUFF TRIANGLE SUBMERGED.

QUARTERMASTER REACH SUBMERGED.

WILDLIFE PROTECTION ZONE HABITAT TEMPORARILY SUBMERGED. GREATER FARALLONES NATIONAL MARINE SANCTUARY CAMPUS INUNDATED. AIRFIELD AND PROMENADE UNDER WATER. MASON STREET STORM DRAINS BUBBLE UP

DUNES UNDER WATER. SAND DEPOSITS ON THE PROMENADE.

NEW LEARNING LANDSCAPE AND PRESIDIO PARKLANDS INUNDATED.

EAST BEACH TEMPORARILY UNDERWATER. EAST BEACH DRAINS BUBBLE UP. PARKING LOT TEMPORARILY INUNDATED. MASON STREET AND MARINA BOULEVARD UNDER WATER.

CYPRESS GROVE COMPROMISED

SPORTS BASEMENT PARKING UNDER WATER.

CRISSY BEACH PROMENADE AIRFIELD

MARSH

EAST BEACH

MASON STREET

PRESIDIO

MAIN POST

100YR TIDE EVENT = A flood height that statistically has a 1-percent chance of occurring in any given year.

100YR TIDE EVENT FREQUENCY = statistically, once every 100 years 100YR TIDE EVENT DURATION = 2 hours per event 40

ELEVATION 9 (NAVD 88)

VULNERABILITY ANALYSIS 3 FT SLR ABOVE CURRENT MHHW

MAR

INE

DRIV

BEACH RETREATS TOWARDS DUNES. DUNES BECOME SHORTER AND NARROWER AND ARE BLOCKED BY THE PROMENADE. SAND DEPOSITS ON THE PROMENADE FROM LACK OF DUNE PROTECTION.

TORPEDO WHARF

INTERTIDAL ZONE LOST. MARSH IS SUBTIDAL.

BEACH WILL RETREAT TOWARDS PROMENADE. BEACH ANGLE OF REPOSE WILL BECOME MORE SHALLOW. SEATWALL FOUNDATION WILL BE UNDERMINED. DUNE WILL BECOME NARROWER AND SHORTER.

ENTRY TO EAST BEACH INUNDATED.

CRISSY BEACH PROMENADE AIRFIELD

MARSH MASON STREET

PRESIDIO

MAIN POST

MHHW = MEAN HIGHER HIGH WATER = The average of the higher high water height of each tidal day observed over the standard 19 year observation period.

MHHW FREQUENCY = 50 times per year MHHW DURATION = 2.2 hours per event

King tide folder - marsh

EAST BEACH

ELEVATION 10 (NAVD 88)

MAR

INE

DRIV

VULNERABILITY ANALYSIS 3 FT SLR ABOVE CURRENT KING TIDE

TORPEDO WHARF

WILDLIFE PROTECTION AREA COMPROMISED MORE FREQUENTLY. WILL BE MORE DIFFICULT TO MAINTAIN ROCKY BREEDING SHORES.

BEACH AND DUNES INUNDATED. DUNES WILL HAVE MORE DIFFICULTY REGENERATING. MORE SAND WILL BE DEPOSITED ON THE PROMENADE.

GREATER FARALLONES NATIONAL MARINE SANCTUARY CAMPUS AND PROMENADE ENTRANCE COMPROMISED. MASON DRIVE STORM DRAINS BUBBLE UP FROM HIGH TIDES.

OVERLOOK COMPROMISED.

EAST BEACH SUBMERGED MORE FREQUENTLY. LONGER PERIODS WHEN BEACH WILL BE CLOSED TO ACTIVE RECREATION AND FAMILIES.

CRISSY BEACH PROMENADE AIRFIELD

MARSH

EAST BEACH

MASON STREET

PRESIDIO

MAIN POST

KING TIDE FREQUENCY = 6-8 times per year KING TIDE DURATION = 1.5 hours per event 42

VULNERABILITY ANALYSIS 3 FT SLR ABOVE CURRENT 100 YR TIDE

ELEVATION 12 (NAVD 88)

WAVES WILL CRASH OVER THE SEAWALL. 11 FT OF WAVE RUNUP EXPECTED.

MAR

INE

DRIV

TORPEDO WHARF

MARSH OVERFLOWS TO MASON STREET. MASON STREET STORM DRAINS BUBBLE UP FROM HIGH TIDES.

WEST BLUFF PICNIC AREAS, PARKING, WARMING HUT, AND PROMENADE INUNDATED.

NEW LEARNING LANDSCAPE AND PRESIDIO PARKLANDS OVERLOOKS UNDER WATER. IMPACT TO HALLECK STREET CONNECTION.

WILDLIFE PROTECTION AREA TEMPORARILY SUBMERGED. AIRFIELD AND HANGARS COMPROMISED. GREATER FARALLONES NATIONAL MARINE SANCTUARY CAMPUS TEMPORARILY CLOSED.

EAST BEACH PARKING, PICNIC AREAS DUNE SWALE, SEATWALL, BATHROOMS, DUNES, BEACH, ENTRY DRIVES, AND ENTRY GROVE TEMPORARILY SUBMERGED.

QUARTERMASTER REACH INUNDATED.

BEACH AND DUNES SUBMERGED.

DOYLE DRIVE CONNECTION TO GOLDEN GATE BRIDGE SUBMERGED. MARINA INUNDATED.

PROMENADE SUBMERGED.

CRISSY BEACH PROMENADE MARSH

AIRFIELD

EAST BEACH

MASON STREET

PRESIDIO

MAIN POST

100YR TIDE EVENT = A flood height that statistically has a 1-percent

DOYLE DRIVE CONNECTION

chance of occurring in any given year.

100YR TIDE EVENT FREQUENCY = statistically, once every 100 years 100YR TIDE EVENT DURATION = 2 hours per event PRE P

ELEVATION 12 (NAVD 88)

VULNERABILITY ANALYSIS 6 FT SLR ABOVE CURRENT MHHW

WAVES WILL CREST OVER SEAWALL FREQUENTLY.

MAR

INE

DRIV

TORPEDO WHARF

WEST BLUFF PICNIC AREAS, PARKING, AMPHITHEATER, AND WARMING HUT ACCESS LOST.

MARSH IS SUBTIDAL. HABITAT LOST.

QUARTERMASTER REACH IS SUBTIDAL. HABITAT LOST.

WILDLIFE PROTECTION AREA LOST. GREATER FARALLONES NATIONAL MARINE SANCTUARY CAMPUS CLOSED.

MASON STREET AND HANGARS FREQUENTLY INUNDATED.

PRESIDIO PARKLANDS IS FREQUENTLY INUNDATED.

EAST BEACH ACTIVITY IS HEAVILY DISRUPTED DUE TO CONSTANT HIGH TIDES. EAST BEACH ACCESS IS CLOSED.

BEACH AND DUNES ARE LOST.

DOYLE DRIVE CONNECTION IS UNDER WATER.

PROMENADE IS COMPLETELY SUBMERGED. CRISSY BEACH PROMENADE MARSH

AIRFIELD

EAST BEACH

MASON STREET

PRESIDIO

MAIN POST

MHHW = MEAN HIGHER HIGH WATER = The average of the higher high water height of each tidal day observed over the standard 19 year observation period.

MHHW FREQUENCY = 50 times per year MHHW DURATION = 2.2 hours per event 44

VULNERABILITY ANALYSIS 6 FT SLR ABOVE CURRENT KING TIDE

ELEVATION 9 (NAVD 88)

FREQUENT INUNDATION AT THE HANGARS WOULD CAUSE PERMANENT DAMAGE. MAR

INE

DRIV

TORPEDO WHARF

HISTORIC AIRFIELD WOULD BE FREQUENTLY SUBMERGED. ACCESS TEMPORARILY LOST. FREQUENT INUNDATION AT THE HANGARS WOULD CAUSE PERMANENT DAMAGE.

CRISSY FIELD CENTER BUILDINGS INUNDATED.

CRISSY BEACH PROMENADE AIRFIELD

MARSH MASON STREET

PRESIDIO

KING TIDE FREQUENCY = 6-8 times per year KING TIDE DURATION = 1.5 hours per event

MAIN POST

EAST BEACH

ELEVATION 8 (NAVD 88)

MAR

INE

DRIV

VULNERABILITY ANALYSIS 6 FT SLR ABOVE CURRENT 100 YR TIDE

TORPEDO WHARF

HISTORIC AIRFIELD WOULD BE TEMPORARILY SUBMERGED. ACCESS TO AIRFIELD TEMPORARILY LOST.

CRISSY BEACH PROMENADE AIRFIELD

MARSH

EAST BEACH

MASON STREET

PRESIDIO

MAIN POST

100YR TIDE EVENT = A flood height that statistically has a 1-percent chance of occurring in any given year.

100YR TIDE EVENT FREQUENCY = statistically, once every 100 years 100YR TIDE EVENT DURATION = 2 hours per event 46

RISK ASSESSMENT

SEVERAL DOCUMENTS (CO-CAT 2013, IPCC 2007, NRC 2012) HAVE DEFINED RISK AS THE PRODUCT OF THE LIKELIHOOD OF DAMAGE AND THE CONSEQUENCE OF DAMAGE, WHICH CAN BE EXPRESSED AS:

RISK = LIKELIHOOD × CONSEQUENCE RISK ASSESSMENT LIKELIHOOD IMPACTS

LIKELIHOOD IMPACTS LIKELIHOOD IMPACTS

HIGH

MEDIUM

LOW

HIGH RISK

MEDIUM RISK

CONSEQUENCE

HIGH

CONSEQUENCE

MEDIUMHIGH RISK

CONSEQUENCE

LOW

MEDIUM RISK LOW RISK

LOW RISK

In this analysis, likelihood is determined by the relative probability that inundation and the associated impacts would occur while consequence is defined by the asset or resource’s sensitivity and adaptive capacity. For example, an event which is highly likely to occur which results in an impact to the function or use of an asset (high likelihood), combined with an asset or resource which has a high sensitivity and low adaptive capacity to sea level rise (high consequence) would have a high risk.

To evaluate risk to an asset, both likelihood and consequence need to be characterized. Likelihood for a lower elevation asset to be inundated even with a small amount of SLR is higher than, say, a building on higher ground. The inundation maps provided in the vulnerability assessment provide elevations for each combination of sea level rise and tidal elevation (e.g. 3 feet of sea level rise above current MHW has an elevation of 9 NAVD88). These elevations serve as an indicator of likelihood, with lower values being more likely than higher ones. It is important to note that some of the vulnerability maps have the same elevation though they represent different levels of sea level rise above different tidal elevations. They should be interpreted differently though because they represent different time periods. For example, both of the maps for 3 feet SLR above current king tide and 1 feet SLR above current 100-yr tide have the same elevation of 10 NAVD88. The consequence of failing to address sea level rise for a particular project will depend on both the sensitivity of the assets to sea level rise and the adaptive capacity of the assets. For example, assets which are highly sensitive to sea level rise and also have a low adaptive capacity will have a high consequence. Assets that have high adaptive capacity and/or low sensitivity will have a lower consequence.

Provided above is a COMPARATIVE ASSESSMENT OF RISK that was conducted for each

of the FOUR ASSET AND RESOURCE GROUPS.

The table to the left shows the likelihood, consequence and overall risk for each of the four assets groups. Overall the risk for each of the assets groups is medium with the natural resources having a higher risk. As you can see the likelihood of inundation for each of the asset groups varies by proximity to the bay, level of sea level rise and frequency of inundation. The historical, archaeological and cultural resources have limited exposure to inundation even under moderate level of sea level rise therefore the likelihood is low to medium, while the natural resources which are generally located adjacent to the bay have a much higher likelihood of inundation. The consequence of a group of assets being impacted by sea level rise varies. The asset groups would all either be moderately or severely impacted by sea level rise, but the adaptive capacity of some groups is much higher than others. For example, the natural resources at Crissy Field would be inundated more frequently by sea level rise, but generally have a high adaptive capacity, which results in a medium consequence. 48

4.0 RISE-UP STAKEHOLDER + COMMUNITY WORKSHOP

An interactive workshop called ‘RISE-UP’ was held on January 30, 2016, inviting the community to imagine a future for Crissy Field under different sea level rise scenarios. Attendees learned about the science of climate change and sea level rise, and were able to view projections for sea level rise at Crissy Field. Participants then engaged in a hands-on game overlaying various adaptation tools onto plans showing 3-foot or 6-foot sea level rise scenarios.

RISE-UP is a sea level rise planning approach that brings scientific, engineering, and design expertise to a community engagement process. RISE-UP’s model codifies community engagement in sea level rise planning into three digestible steps:

1. SEA LEVEL RISE OVERVIEW Presentation to the community, including sea level rise basics; asset and vulnerability mapping; and adaptation inventory and assessment.

2. SEA LEVEL RISE PLANNING GAME Engaging the community with the Game of Tides to gather feedback on adaptation strategies.

3. SEA LEVEL RISE VISION Presentation of community’s results.

RISE-UP COMMUNITY WORKSHOP

The one-day workshop began with expert presentations of Sea Level Rise predictions and adaptation strategies at Crissy Field, continued to seven 5-10 person teams playing the planning game “Game of Tides”, and concluded in team report-outs. As teams were assigned at random, the game catalyzed discussions among neighbors and strangers alike. Sometimes agreeing and sometimes not, teams rose to the occasion of reconciling many voices to resolve a single adaptation for their study area. As a pilot community engagement tool, RISE-UP brings an informed, participatory process to sea level rise planning. As a popular and highly visible national park site, Crissy Field’s sea level rise future is uniquely primed to be informed by its vast and passionate constituencies, stand as a demonstration site for sea level rise adaptive management, and advance RISE-UP’s replicability as a model of community engagement on sea level rise planning. RISE-UP integrates climate projections and coastal engineering expertise with user-base feedback into a synthesized sea level rise informational report.

CHRIS LEHNERTZ, NPS; KEVIN CONGER, CMG; DILIP TRIVEDI, M&N; AND JAMIE PHILLIPS, CMG GAVE A PRESENTATION ON SEA LEVEL RISE TO THE COMMUNITY.

WORKSHOP PARTICIPANTS STUDIED THE ASSET MAPS, SEA LEVEL RISE VULNERABILITY ANALYSIS MAPS, AND SEA LEVEL RISE BASICS INFORMATION.

RISE-UP COMMUNITY WORKSHOP

WORKSHOP PARTICIPANTS WERE DIVIDED INTO SEVEN GROUPS AND PLAYED THE GAME OF TIDES. EACH GROUP GAVE A BRIEF PRESENTATION OUTLINING THEIR RECOMMENDATIONS ON HOW TO APPLY EACH STRATEGY AT CRISSY FIELD.

GAME OF TIDES GAME BOARDS

EACH GROUP WAS ASKED TO 'SOLVE' FOR EITHER 3 FEET OR 6 FEET OF SEA LEVEL RISE, DEPENDING ON WHICH OF THE FOLLOWING GAME BOARDS THEY WERE GIVEN:

FFE 14 FFE 12

FFE 14

+ FFE 12 +

+ FFE 12.5 FFE 11.5

FFE 12

+ FFE 12.5 +

3' SLR ABOVE CURRENT MHHW ELEVATION 9 3’ SLR ABOVE CURRENT KING TIDE ELEVATION 10 3’ SLR ABOVE CURRENT 100 YR TIDE ELEVATION 12 OUTLET

+ FFE 10.5

ELEV ATIO N

+ FFE 13

FFE 13

E EL LEVA EV TIO ATIO N N1 9 0

FFE 12.5

+ FFE 12

+ + FFE 13.5

ELEV ATION 12 ELEV ATION 10

+ FFE 16 + FFE 15 +

+ FFE 11.5

+ FFE 12

FFE 16

+ FFE 12

FFE 13

+ FFE 12

FFE 12.5

+ FFE 12.5

3 FT SEA LEVEL RISE

FFE 14 FFE 12

FFE 14

+ FFE 12 +

+ FFE 12.5 FFE 11.5

FFE 12

+ FFE 12.5 +

6’ SLR ABOVE CURRENT MHHW ELEVATION 12 6’ SLR ABOVE CURRENT KING TIDE ELEVATION 13 6’ SLR ABOVE CURRENT 100 YR TIDE ELEVATION 15 OUTLET

6 FT SEA LEVEL RISE

E EL LEVA EV TIO ATIO N N1 9 0

ELEV ATIO N

+ FFE 13

FFE 13

+ FFE 10.5

FFE 12.5

+ FFE 12

+ + FFE 13.5

ELEV ATION 12 ELEV ATION 10

+ FFE 16 + FFE 15 +

FFE 16

+ FFE 12 + FFE 12

FFE 13

+ FFE 12

FFE 12.5

+ FFE 12.5

FFE 12.5

+ FFE 11.5

THE GAME PIECES WERE GIVEN TO GROUPS TO ALLOW FOR THEM TO 'SOLVE' FOR 3 OR 6 FEET OF SEA LEVEL RISE, RESPECTIVELY. EACH GAME PIECE WAS EXPLAINED IN THE FOLLOWING WAY:

ALLOW WATER LEVELS TO RISE. ABANDON AND DECONSTRUCT PARKLANDS, BUILDINGS, UTILITIES AND ROADS BEFORE THEY EVENTUALLY FLOOD.

LOOSE STONE USED TO ARMOR VULNERABLE SHORELINES AND PROTECT SHORELINES FROM EROSION OR SCOUR.

WAVE ATTENUATION IS ACHIEVED THROUGH BEACHES AND OFFSHORE ARTIFICIAL REEFS BEFORE WAVES REACH SHORE. BEACHES ACT AS SAND ENGINES.

RETREAT

RIPRAP

REEF

BEACH NOURISHMENT IS IMPORTING OR PUMPING SAND FROM ELSEWHERE ONTO AN ERODING SHORELINE TO MAINTAIN A BEACH.

VERTICAL WALL HOLDS WATER BACK. IT CAN FIT IN NARROW HORIZONTAL SPACES. SEAWALL CAN BE RETAINING WALL OR FREESTANDING. SEAWALLS CAN CUT OFF WATERFRONT VIEWS.

WETLANDS PLAY A NUMBER OF ROLES IN THE ENVIRONMENT SUCH AS WATER PURIFICATION, FLOOD CONTROL, CARBON SINK AND SHORELINE STABILITY. WETLANDS ARE CONSIDERED A “LIVING SHORELINE” ECOSYSTEM IN WHICH A WIDE RANGE OF PLANTS AND ANIMALS CAN PROSPER.

SEAWALL

WETLAND

HILL OF SAND NEAR A BEACH ON SHORELINES. DUNES FORM BY INTERACTION WITH THE FLOW OF AIR OR WATER. DUNE HABITATS PROVIDE A RECESS FOR HIGHLY SPECIALIZED PLANTS AND ANIMALS INCLUDING RARE AND ENDANGERED SPECIES.

LINEAR EARTHEN BERM PROTECTION. LEVEES ARE THE MOST TRADITIONAL FLOOD PROTECTION STRATEGY. THEY ARE LESS EXPENSIVE THAN MOST SOLUTIONS BUT THEY REQUIRE MEDIUM HORIZONTAL DISTANCE AND SIGNIFICANT MAINTENANCE.

AN ATTACHMENT FOR PIPES AND WATER UTILITIES THAT ALLOW WATER TO EXIT THE SYSTEM BUT PREVENT HIGH TIDE WATER FROM ENTERING THE PIPES.

DUNE

LEVEE

WALKWAY ELEVATED OR FLOATING

ELEVATED OR FLOATING WALKWAYS ALLOW VISITORS TO EXPERIENCE THE PARK WHILE IT IS UNDERWATER. PILINGS AND FOOTINGS ARE REQUIRED FOR ELEVATED WALKWAYS. FLOATING WALKWAYS ARE SUCCESSFUL IN PROTECTED WATERS ONLY.

DUCKBILL FLAPS

ADAPTABLE BUILDINGS FLOATING, ELEVATED, OR FIRST FLOOR FLOODABLE BUILDINGS. TYPICALLY A SHORT TERM SOLUTION, NOT ALWAYS RESILIENT TO EXTREME WIND AND WAVES.

BEACH

GAME PIECES GAME OF TIDES

PUMP STATIONS PUMP STATIONS ARE FACILITIES THAT USE ELECTRIC PUMPS AND MECHANICAL EQUIPMENT TO DRAIN LOW-LYING LAND FROM HIGH WATERS. FLOODCONTROL PUMP STATIONS ARE GENERALLY LOCATED ON LEVEES.

GAME OF TIDES GAMEBOARD RESULTS FOR 3 FEET OF SLR BELOW ARE THE RESULTING GAME BOARDS AND NOTES FROM THE TEAMS SOLVING FOR 3 FEET OF SEA LEVEL RISE.

TEAM 1

TEAM 2

NOTES:

Can we move the buildings? Tidal Gauge? Keep! Non-Nourished Beach Edge Nourish Beach Edge Snowy Plover City Kayak Share TM

Retreat in area of marsh, allow to become more natural Re-route promenade behind marsh and along Mason Street Remove former commissary and expand marsh Retreat/natural processes at historic Coast Guard Station Add reefs offshore from Marine Drive Protect East Beach with seawall and rip-rap Route Mason Street back towards Doyle Drive east of former commissary Water Recreation Kayak Crissy Field Walkway through marsh and back to Mason Street Allow beach to overflow promenade Allow beach to expand into marsh Beach retreats south over time Adapt / Elevate historic Coast Guard Station Keep rip-rap at Marine Drive Protect Torpedo Wharf, Warming Hut and Historic Buildings

TEAM 3

TEAM 4

NOTES:

Priorities Infrastructure Historic structures Recreational and social spaces at airfield Dune protection East Beach recreation area Protect with wetlands tracing historic footprint but maintain recreational use with elevated walkways Utilize wetlands to expand habitat Longer Term Levees at Mason Street and pair with duckbill flaps and pumps

Torpedo Wharf to Fort Point – add sea wall protection with reefs and strengthen wall Protect buildings at Torpedo Wharf – add pump station Retreat. Let it happen. Another inlet at marsh Widen existing marsh inlet Nourish dunes for 5-10 years Nourish beaches and add dunes to protect Airfield Dunes stable if protect the opening at Fort Point Nourish beach for 5-10 years Make the Snowy Plover Habitat bigger Reef may not work, waves too strong Protect reef with rip-rap

Focus on natural system - interventions The whole beach is important Cautious about spending on infrastructure Keep the historic Coast Guard Station Expanded uses up onto Parade Ground Thoughtful retreat Sand Engine sounds cool Combination approach = reef + beach + dune + walkway At 3’ of sea level rise, wetlands protect Mason Street At 6’ of sea level rise, you need a levee? What about the costs? Values Recreation Public access Conserve habitat Historic Natural Solutions Snowy Plover Surfing 58

GAME OF TIDES GAMEBOARD RESULTS FOR 6 FEET OF SLR BELOW ARE THE RESULTING GAME BOARDS AND NOTES FROM THE TEAMS SOLVING FOR 6 FEET OF SEA LEVEL RISE.

TEAM 6

TEAM 7

NOTES:

Love it the way it is! Return to all wetlands Extend wetlands to Yacht Club and beyond Put in walkways to be near water Levee close to historic buildings to protect Retreat at historic Coast Guard Station, move buildings to higher ground Make Mason Street the levee and use to protect historic buildings Add Duckbill Flaps and pumps behind levee Former Commissary building planning in place should incorporate sea level rise (adapted) Use reefs to help protect wetlands and dissipate wave action Wetlands are a form of retreat Missing the beach - Nourish / build up a small area for beaches

Planted Levee Elevate Mason Street historic buildings Raise Mason Street on levee to protect historic buildings Remove former Commissary building Nourish dunes to protect airfield â&#x20AC;&#x201C; protect most of airfield Do not protect less important historic structures Do not relocate or move historic structures Raise Coast Guard Station. Historic importance relates to coastal proximity Remove promenade â&#x20AC;&#x201C; move pedestrian, bikes and cars to Mason Street

Focus beach nourishment in areas where natural current will disperse sand to grow beach (sand reservoir- Dutch innovation) Electric tidal dam at golden gate Reefs/oyster farm offshore Hard infrastructure (like levees) should serve dual purpose, ecosystem, recreation, etc. Fortify seawall Protect Torpedo Wharf

SEA LEVEL RISE PLANNING GAME Workshop attendees left informed about sea level rise opportunities and challenges, and invested in implementation at a park they know and love. The National Park Service and Parks Conservancy learned more about which areas of Crissy Field are most valued and why, through the processes of making decisions around what to protect, adapt or remove.

TEAM 10 NOTES: Walkways! Human Access to the Shoreline Beautification No Retreating, but Least invasive Sand, Sand and More Sand! Sand and Dunes! Wetlands! Put wetlands everywhere. Reef Levee to Protect Buildings At Mason Street Add Rip-rap and Seawall to protect Fort Point Least Cost Forget the buildings Keep existing functions What will the cost be? Least invasive and least cost

5.0 ADAPTATION SCENARIOS THE SEVEN GAME OF TIDES GAMEBOARDS GENERATED AT THE WORKSHOP WERE FURTHER ANALYZED BASED ON THE FOLLOWING FOUR ADAPTATION STRATEGIES TO DEMONSTRATE HOW INFORMED INPUT OF PROFESSIONALS AND COMMUNITY MEMBERS COULD BE USED TO GENERATE FUTURE PLANNING SCENARIOS.

RETREAT Remove buildings or hard infrastructure, and replace with natural amenities like wetlands which are more resilient to sea level rise over time.

PROTECT Protect the existing resource with both ‘hard’ or ‘soft’

DURING ANALYSIS, WE SYNTHESIZED THE GAMEBOARDS WITH SIMILAR STRATEGIES, AND COMBINED THEM INTO FOUR ADAPTATION SCENARIOS DESCRIBED ON THE FOLLOWING PAGES. THE FOUR SCENARIOS REPRESENT A RANGE OF SOLUTIONS FROM MINIMAL TO EXTREME.

TEAMS 2 + 4 EXPANDED TIDAL MARSH: Gameboards were combined to illustrate a minimal approach toward solving for 3 feet of sea level rise.

TEAMS 3 + 7 PROTECT CULTURAL + HISTORIC RESOURCES: These

design strategies.

teams focused their efforts on protecting the airfield and the historic buildings in place.

ADAPT Adapt the asset, like a building, to be resilient to sea level rise.

TEAMS 6 + 10 RETREAT + PROTECT: At six feet of sea level rise,

Raise the finish floor elevation of the building to be above projected elevations for sea level rise. Adapt the first floor of the building to be floodable during extreme high tide events.

most of Crissy Field is inundated. These teams proposed raising the elevation of Mason Street to create a levee which protected the existing historic buildings south of Mason Street, and constructed a wetland through most of the park.

ACCESS Providing pedestrian access in new locations as needed, to provide access to the cultural, recreational and natural assets of the park.

TEAM 1 FULL RETREAT: This team proposed an exuberant retreat scenario, expanding the marsh across the airfield and removed the existing historic buildings south of Mason Street.

DIAGRAMS ILLUSTRATE THE ACTIONS OF PROTECT, RETREAT, ADAPT AND ACCESS IN THE 4 SYNTHESIZED SCENARIOS.

TEAMS 2+4

TEAMS 3+7

TEAMS 6+10

TEAM 1 62

The gameboards for teams 2 and 4 were synthesized into one adaptation scenario because both teams took a practical and minimal approach to solving for three feet of sea level rise. Both teams provided pumps and duckbill flaps in the short term to protect Mason Street from flooding and retreated by expanding the marsh into the area currently occupied by the former Commissary. The two teams also protected the Marine Drive seawall with riprap or reefs, and because the promenade was minimally affected by sea level rise, kept the access in its current location.

RETREAT

Remove former Commissary and expand marsh south. Allow beach to retreat as sea levels advance.

PROTECT

Add a seawall to protect Torpedo Wharf. Add seawall and rip-rap to protect East Beach. Provide duckbill flaps and pumps.

ADAPT

Raise finish floor elevation of historic Coast Guard Station to Elevation 13.5.

ACCESS

Maintain existing promenade in place.

TEAM 2 GAMEBOARD SOLVING FOR 3 FEET OF SLR

TEAM 4 GAMEBOARD SOLVING FOR 3 FEET OF SLR

DIAGRAM ANALYZING PRIMARY ACTIONS UNDERTAKEN BY TEAM 2 + 4

EXPANDED TIDAL MARSH

SEAWALL/GATE TO PROTECT HISTORIC BUILDINGS ADAPT HISTORIC COAST GUARD STATION, RAISE FINISH FLOOR ELEVATION TO 13.5 ADD DUCKBILL FLAPS AND PUMP STATIONS REMOVE FORMER COMMISSARY AND EXPAND MARSH RIPRAP AND SEAWALL TO PROTECT EAST BEACH ELEVATION10 KING TIDE +3FT

We combined the plans for teams 3 and 7 because these teams focused their efforts expanding the marsh toward the east, similar to its historic configuration, nourishing the existing dunes to protect the airfield, and raising the elevation of Mason Street to protect the existing historic buildings from rising seas.

RETREAT

Expand wetland to the east. Remove former commissary building.

PROTECT

Create a levee at Mason Street. Raise to Elevation 13.5. Import sand to supplement dune to protect historic Coast Guard Station and airfield. Reinforce seawall at Marine Drive, and add seawall and pumps to protect Torpedo Wharf. Provide duckbill flaps and pumps. Mason Street levee protects existing buildings.

ADAPT

Raise finish floor elevation of existing historic buildings.

ACCESS

Provide elevated walkway for recreational access through new east wetland.

TEAM 3 GAMEBOARD SOLVING FOR 3 FEET OF SEA LEVEL RISE

TEAM 7 GAMEBOARD SOLVING FOR 6 FEET OF SEA LEVEL RISE

DIAGRAM ANALYZING PRIMARY ACTIONS UNDERTAKEN BY TEAM 3 + 7

PROTECT CULTURAL + HISTORIC RESOURCES

REEF FOR WAVE ATTENUATION SEAWALL OR GATE TO PROTECT HISTORIC BUILDINGS EXTEND SEAWALL ADAPT HISTORIC BUILDING - RAISE FINISH FLOOR ELEVATIONS TO 13.5 PROTECT OR KEEP BUILDING RAISE MASON STREET TO ELEVATION 13.5 NOURISH DUNES AND BEACH TO PROTECT AIRFIELD REMOVE FORMER COMMISSARY RAISE MASON STREET TO ELEVATION 13.5 ADD MARSH INLET EXPAND MARSH

ELEVATION10 KING TIDE +3FT

At six feet of sea level rise, most of Crissy Field is inundated at mean higher high water. These teams proposed raising the elevation of Mason Street to create a levee which protected the existing historic buildings south of Mason Street, and constructing a wetland throughout the majority of Crissy Field.

RETREAT

Retreat back to Mason Street.

PROTECT

Create a levee at Mason Street. Raise to Elevation 13.5. Reinforce seawall at Marine Drive, and add seawall at Torpedo Wharf. Provide duckbill flaps and pumps. Sea wall, levee and pumps protect existing buildings.

ADAPT

Move historic Coast Guard building south of Mason Street.

ACCESS

Provide elevated walkway for recreational access through wetland.

TEAM 6 GAMEBOARD SOLVING FOR 6 FEET OF SEA LEVEL RISE

TEAM 10 GAMEBOARD SOLVING FOR 6 FEET OF SEA LEVEL RISE

DIAGRAM ANALYZING PRIMARY ACTIONS UNDERTAKEN BY TEAM 6 + 10

RETREAT NORTH OF MASON STREET

REEF FOR WAVE ATTENUATION SEAWALL/GATE TO PROTECT HISTORIC BUILDINGS EXTEND SEAWALL RAISE MASON STREET TO ELEVATION TO 13.5 ADAPT AND RELOCATE HISTORIC COAST GUARD STATION ELEVATED WALKWAY ADAPT FORMER COMMISSARY BEACH ADAPT HISTORIC BUILDINGS

ELEVATION13 KING TIDE +3FT

The gameboard for Team 1 exhibits the most aggressive retreat approach documented at the workshop. This team expanded the marsh throughout the majority of Crissy Field and removed the historic buildings south of Mason Street.

TEAM 1 GAMEBOARD SOLVING FOR 3 FEET OF SEA LEVEL RISE

RETREAT

Expand wetland west into airfield. Remove existing buildings south of Mason Street. Remove historic coast guard station.

PROTECT

Add seawall to protect Torpedo Wharf. Provide duckbill flaps and pumps.

ACCESS

Provide recreational access along Mason Street, with access to the beach at the east and west ends.

DIAGRAM ANALYZING PRIMARY ACTIONS UNDERTAKEN BY TEAM 1

FULL RETREAT

SEAWALL/GATE TO PROTECT HISTORIC BUILDINGS PROVIDE DUCKBILL FLATS AND PUMP STATIONS REMOVE HISTORIC COAST GUARD STATION PROVIDE BOARDWALKS TO THE WATER'S EDGE RELOCATE PROMENADE TO ALIGN WITH MASON STREET REMOVE HISTORIC BUILDINGS, REPLACE WITH PARKLAND MARSH ELEVATION10 KING TIDE +3FT

TO CREATE THIS WORD CLOUD, WE COUNTED THE NUMBER OF TIMES EACH GAME PIECE WAS USED AT THE WORKSHOP ON THE GAME OF TIDES. 'WETLAND' WAS THE MOST POPULAR GAME PIECE.

SCENARIO SUMMARY

THE ADAPTATION SCENARIOS DOCUMENT A SYNTHESIS OF THE IDEAS GENERATED AT THE RISE-UP WORKSHOP. Workshop attendees left informed about sea level rise opportunities and challenges, and invested in implementation at a park they know and love. They expressed a comfort level with the resiliency of Crissy Field, embraced wetland creation and took steps to protect important cultural and historic assets. The National Park Service and Parks Conservancy learned more from the community about which areas of Crissy Field are most valued and why, through the processes of making suggestions on what to protect, adapt or remove.

6.0 NEXT STEPS The CRISSY FIELD + SEA LEVEL RISE-UP documents a research and stakeholder process for understanding how sea level rise will affect Crissy Field for future planning and implementation efforts. The sea level rise analysis of Crissy Field is highly complementary to broader planning efforts, and this information will help guide future design decisions. In addition to the direct community outreach that was conducted through this project, the resulting information and materials will also be incorporated into the ongoing education and interpretive programming of the National Park Service and Parks Conservancy. Going forward, this sea level rise analysis and community engagement effort will help guide the allocation of federal and philanthropic resources to best serve the public, preserve natural and cultural resources, and increase resiliency.

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ACKNOWLEDGMENTS

GOLDEN GATE NATIONAL PARKS CONSERVANCY

CALIFORNIA STATE COASTAL CONSERVANCY

Catherine Barner Anne Baskerville John Skibbe Jennifer Greene Chase Jaz Natalya Blumenfeld Kathleen Knighton Oksana Shcherba

Sam Schuchat Kelly Malinowski

NATIONAL PARK SERVICE Christine Lehnertz Carey Feierabend Brian Aviles Stephen Haller Daphne Hatch Kristen Ward Dan Collman Will Elder Laura Castellini

CMG LANDSCAPE ARCHITECTURE Kevin Conger Jamie Phillips Jennifer Ng Annabelle Hernandez Hyunjoo Nam Alexandra Zahn Lucy McFadden

MOFFATT & NICHOL Dilip Trivedi Christopher Devick

THE CITIZENRY And thanks to all the engaged citizens who took the time to attend the workshop.

PRESIDIO TRUST Paul Scardina Mark Hurley Rob Thomson

CREDITS: UNLESS OTHERWISE NOTED, CMG LANDSCAPE ARCHITECTURE AND MOFFATT & NICHOL PREPARED ALL PHOTOS, GRAPHICS AND RENDERINGS.