JAMAICA BAY: FLUID LANDSCAPE
REPAIRING AN URBAN ESTUARY THROUGH TIDAL MANIPULATION
ANDREA NICOLETTA HAYNES MASTERS OF LANDSCAPE ARCHITECTURE DESIGN THESIS CORNELL UNIVERSITY 2014
AKNOWLEDGEMENTS THANK YOU Dr. Philip Liu In The Cornell School Of Civil And Environmental Engineering for technical advice on marine dynamics Chelsea Morris In the Soil And Water Lab at Cornell Professor Peter Trowbridge for starting me on this journey into Jamaica Bay My advisor Professor Brian Davis for inspiration and motivation, being available, completely engaged, and all around brilliant Mr. Marc Miller for having the mind of a scientist and the eye of an artist All my dear friends and colleagues in the Department of Landscape Architecture And most of all to my fiancĂŠ for his constant support, advice, and encouragement
CONTENTS 01
INTRODUCTION
02
BAY DYNAMICS
03
SEDIMENT INTERRUPTION
04
SYNTHESIS + DESIGN
05
DESIGN ANALYSIS
01 INTRODUCTION The Jamaica Bay is unique within the United States as a National Park, an urban estuary, National Recreation Area and wildlife refuge. The ecosystem services provided in the form of wildlife habitat and flood protection are of great value for the local and regional biodiversity, recreation, and adjacent neighborhoods’ flood protection. This tidal estuarine ecosystem is under threat from low water quality, interruption of the sediment cycle, and projected sea level rise. At the mouth of the Jamaica Bay, the Rockaway Inlet, is Floyd Bennett Field. This historic airfield is an underutilized National Park with dozens of derelict buildings and former runways comprised of approximately 500,000 square feet of concrete. With future climate change we can expect not just higher sea levels but more intense and more frequent storm surges. The slow disaster of sea water submerging the marshes and sudden shocks of storm water erosion will mean the destruction of this important habitat if dramatic steps are not taken to protect it.
1
2014
SALT MARSH AREA TODAY: 130 ACRES
0’
6000’
2050
2050
SALT MARSH AREA 2050: 14 ACRES
0’
2050: PROJECTED SEA LEVEL RISE 31” [1]
6000’
0’
6000’
2050: SEA LEVEL RISE + 8’ STORM SURGE
2
PREDICTED 2050 SEA LEVEL RISE
JFK AIRPORT
PREDICTED 2050 SEA LEVEL RISE + 8’ STORM SURGE
FLOYD BENNETT FIELD
0’
6000’
[1]
SEA LEVEL RISE + FUTURE STORMS
sea level rise according to NOAA
High predictions of
HURRICANE SANDY: EFFECTS ON NEW YORK CITY
for New York City coast line
Expected
51 lives lost 650,000 homes damaged or destroyed
2 million customers without power for up to 4 days Damage to transit Infrastructure:
loss
of marshes:
31� by 2050
116 acres
According to IPCC, with climate change we can expect
stronger, more frequent storms
$5 billion
14-foot storm surge in New York City
JAMAICA BAY + SALT MARSHES
Homeowner and residential property claims:
501,447 for $2.1 billion Auto claims:
$1.5 billion
$3.2 billion
in flood insurance claims
marshes provides
habitat for 325 species of birds
35 species of butterflies 100 species of fish
Total damage estimates:Â
$42 - $55 billion
supports
breeding activities of 70 bird speices
critical
References [2-5]
reduce intensity of storm surges
stopover point for
migratory birds
4
The vulnerabilities inherent in the current land use in and around Jamaica Bay and other coastal areas was made clear to the New York City region during Hurricane Sandy. While billions of dollars in repairs has helped homeowners and businesses recover from this single storm, without addressing the underlying vulnerabilities, this kind of damage will occur again and future storms are expected to be even more destructive. The interventions made in Jamaica Bay over the past two centuries have dramatically altered what was a fundamentally stable system that provide protection from storm events.
5 [6]
02 BAY DYNAMICS In order to understand how to make a more resilient and healthy Jamaica Bay, its history and the complex interrelationship between land and water, that is an estuary, must first be understood. The constant exchange of sediment and movement of what is solid land, marshy, or open water is a part of an unadulterated estuary. Jamaica Bay is a semi-diurnal tidal estuary, meaning it had two high and two low tides per day that bring salt water into a primarily fresh water body. These tidal currents have the capacity to transport sediment and to create tidal deltaic deposits on the bay sides or ocean sides of the inlet, thereby sequestering sediment that would otherwise be transported alongshore [7]. The variety of salinity levels results in high levels of biodiversity. The tides also bring in fish and other sea creatures for birds to feed on and the relatively still and shallow waters within an estuary provide breeding and nursery grounds for a wide variety of avian and marine life. The human interventions within and along the edges of the Bay have had a lasting and profound impact upon its current conditions. Until the early 20th century very few people lived in the vicinity 7
of the bay, it was unnavigable and teaming with oysters. Farming communities in The Flatlands, Canarsie, and New Lots grazed their livestock on marsh grasses and supplemented their diets with oysters. In the 1860’s the practice of seeding of oysters became prevalent and commercial development soon followed. To better boat access to the oyster beds, dredging of channels began. With improved rail and road building technology came an expansion of the Long Island Railroad through the bay, connecting the mainland to Rockaway Peninsula. Hotels, resorts, and vacation homes soon followed. Continued dredging and filling to accommodate boat traffic and settlements has dramatically changed the profile of the edge and islands in the bay. The nourishment of beaches on the ocean side of the Rockaway Peninsula has also changed path through which water enters the bay. Formerly, water entered through multiple inlets and through wetlands and across many small islands. Littoral drift, the process of sand moving nearly parallel to a beach causing it to expand, is a natural part of shoreline dynamics. In the case of the Rockaway Peninsula, the drift is toward the southwest. Sand
JAMAICA BAY IN 1879 [9]
1879
1845
BARREN ISLAND
0’
6000’
dredged from inside the Hudson Bay for navigation channels and elsewhere has been added to the Rockaway beaches to ensure their stability. This has magnified the southwestward growth of the peninsula. This combined with the filling of Barren Island (which became Floyd Bennett Field) has meant tidal waters now go through a narrower and longer inlet. This results in higher velocities which encourages either transport or erosion of sediment, rather than deposition [8].
9
BASED ON NOAA SOUNDINGS MAPS [9]
0’
6000’
0’
6000’
1931
1900
1924
0’
6000’
1941
0’
6000’
0’
6000’
2014
0’
6000’
The range of water level between high and low tide is in constant flux but can be reliably predicted. The influence of the sun and moon on tides gives rise to spring and neap tides. Shortly after the new moon and full moon the sun and moon are both in their closest position to the earth and their combined gravitational pull on the oceans results in a wider range between high and low tides, known as spring tide. Between spring tides, when the pull of the sun and moon is reduced, high and low tide are less extreme.
HT
DAY
MHHW (+5.59’)
MSL (+2.07’)
MLLW (O.O’) LT new
LT
full
MOON
MHHW (+5.59’) MONTH
Although in constant flux but there is a clear pattern and parameters that we can anticipate and design within. The average of low tides, mean low low water (MLLW) is used as the zero mark and mean sea level (MSL) is currently 2.07’ above that in Jamaica Bay. Mean high water (MHHW) is another 3.52’ above MSL.
HT
MSL (+2.07’) MLLW (O.O’) SPRING
SPRING TIDE tidal range at its maximum
NEAP
SPRING
NEAP
NEAP TIDE tidal range at its minimum
MHHW (+ 5.59’) MSL (+2.07’) MLLW (0.0’)
BASED ON DATA FROM NOAA SEE REFERENCE [10]
11
FALL OX EQUIN
MHH W( +5 .59 ’) MS L( +2 .07 ’) MLL W (0. 0’)
ER WINT E TIC SOLS January 1
ER SUMM CE TI SOLS
-2’ 0’ 2’ 4’ 6’
G SPRIN X O EQUIN
8’
12
MAXIMUM RANGE BETWEEN HIGH & LOW TIDE, LARGEST VOLUME OF WATER
FLOOD TIDE
SPRING TIDES:
MIDDLE OF FLOOD TIDE
END OF FLOOD TIDE
MIDDLE OF EBB TIDE
END OF EBB TIDE
EBB TIDE
BEGINNING OF FLOOD TIDE
BEGINNING OF EBB TIDE
Spring tides are the time of maximum tidal range, during which the highs are highest and the lows are lowest. This also means that the amount of water moving through the inlet is at its maximum. The larger volume of water results in higher velocities. The time it takes for the water to enter the bay (flood tide) is shorter than the time it takes for it to leave (ebb tide), therefore the flood tide moves faster and more red is seen in the narrow inlet. 13
LOWEST RANGE BETWEEN HIGH AND LOW TIDE, SMALLEST VOLUME OF WATER
FLOOD TIDE
NEAP TIDES:
MIDDLE OF FLOOD TIDE
END OF FLOOD TIDE
MIDDLE OF EBB TIDE
END OF EBB TIDE
EBB TIDE
BEGINNING OF FLOOD TIDE
BEGINNING OF EBB TIDE 1
0.8
0.6
0.4
0.2
0 m/s
BASED ON DATA FROM STEVEN’S INSTITUTE SEE REFERENCE [11]
Neap tides are the phase during which the lows and highs are closer in range. Therefore the amount of water moving in and out of the bay is lower and the overall velocities are lower. A similar pattern is evident in the neap’s flood and ebb, where the flood tides tend to move faster into the bay, while the ebbs are lower velocities exiting the bay. 14
full
new
The variability in length between the flood and ebb tides has a significant impact on how the system functions. The length of time it takes for the flood and the ebb to occur are frequently asymmetrical due to the capacity of inlet(s) and the bathymetry of a given estuarine system. If the mean duration of the ebb tides exceeds the mean duration of the flood tides there is potential for net sediment input.
IF THE MEAN EBB TIDE DURATION EXCEEDS MEAN FLOOD TIDE DURATION THERE IS POTENTIAL FOR
DURATION OF TIDE CHANGE (EBB TIDE= HIGH TIDE MINUS LOW TIDE)
MOON
18 H 16 H 14 H 12 H
EBB TIDE MEAN=9.58 HOURS
10 H 8H 6H 4H
SPRING
NEAP
SPRING
new
full
DURATION OF TIDE CHANGE (FLOOD TIDE= LOW TIDE MINUS HIGH TIDE)
SUM 20 H 18 H 16 H 14 H 12 H
FLOOD TIDE MEAN=8.82 HOURS
10 H 8H 6H 4H
NEAP
SPRING
SPRING TIDE tidal range at its maximum
15
NEAP
MOON
NET SEDIMENT INPUT
Jamaica Bay is a slightly ebb tide dominant system and therefore has potential for net sediment input. Other factors such as velocity and particulate type determine if, and how much, accretion may occur.
20 H
NEAP
SPRING
NEAP TIDE tidal range at its minimum
BASED ON DATA FROM NOAA SEE REFERENCE [8]
X QUINO FALL E
EBB T IDE ME AN 9.5 8
MEAN EBB TIDE DURATION IS 8.6% GREATER THAN MEAN FLOOD TIDE DURATION
8 AN ME DE TI S OD LO
HO UR F
ICE
T SOLS INTER
HOURS .82
W
TICE
SOLS
4 8 12 16
OX EQUIN
20 HOURS
G SPRIN
ER SUMM
January 1
16
03 SEDIMENT INTERRUPTION Estuaries are formed when fresh water creeks, carrying sediment, empty into a protected bay [11]. Over hundreds or thousands of years this sediment fills the bay with enough material that marsh grasses can take hold. In Jamaica Bay, as with all estuaries, many creeks had been emptying sediment rich fresh water from a large watershed into the bay for thousands of years. Over time, all of these creeks have been filled in and nearly all of the surroundings have been paved over. In addition to the prevalence of impervious surface, the deepening of the bay overall and the cutting of deep channels has a negative impact on marsh health. The surface area since the mid-19th century has nearly halved yet the volume of the bay has increased 350%. From 1974 to 1999 620 acres of Jamaica Bay’s marshes were lost. This drastic loss of marsh area is even effecting the hydrodynamics of the bay and Spring tide range has increased by 20% as compared to the 1950’s [7]. Storm water no longer runs across the surface of farmland or forests 17
bringing sediment with it, instead, moderately polluted runoff from streets, sometimes combined with sewage, is released into the bay resulting in a negative sediment budget. Due to historic and current day dredging activities, what sediment that does reach the bay settles to the bottom of deep channels where marine life does not flourish. The steep walls of the channels are unstable and the adjacent to marsh areas are prone to erosion and collapse [8]. Salt marsh grasses (Spartina alternafolia) are the land builders of an estuary ecosystem. Where there is shallow, relatively still water, these grasses are able to grow. The blades of grasses slow tidal waters and allow sediment in transport to be deposited. The combination of the plants debris and the sediment they trap build up a peat layer, which in turn allows more grasses to be established. Although adapted to the rising and falling of brackish water, they cannot be completely submerged for very long before dying [11].
IMPERVIOUS SURFACES SURROUNDING THE BAY AND HISTORIC CREEKS [12]
18
HOOK CREEK
HASSOCK CREEK
CORNELL’S CREEK
DENTON’S CREEK
REMSEN’S CREEK
BEDFORD CREEK
WATERSHED AREA: 90,880 ACRES
1845
0’
19
A SHALLOW BAY WITH MANY CREEKS FEEDING INTO IT AND SOFT EDGES ALL AROUND, BASED ON NOAA SOUNDINGS MAPS AND USGS TOPOGRAPHIC MAPS [13]
6000’
WATERSHED AREA: 90,880 ACRES
2014
0’
6000’
TODAY’S BAY HAS MANY DEEP CHANNELS AND NO CREEKS FEEDING INTO IT, BASED ON NOAA SOUNDINGS MAPS AND USGS TOPOGRAPHIC MAPS [13]
20
21 MARSHES EDGES ARE STABLE WHEN THE ANGLE IS UNDER 45 DEGREES
GREATER THAN 45 o
ROCKAWAY PENNINSULA
BROAD CHANNEL
RUFFLE BAR
FISHKILL CHANNEL
BIG CHANNEL
CANARSIE POL
CANARSIE
1000x VERTICAL EXAGERRATION
1845
0 4000’
2014
ROCKAWAY PENNINSULA
NAVIGATION CHANNEL
BIG EGG MARSH
BROAD CHANNEL
RUFFLE BAR
FISHKILL CHANNEL
CANARSIE POL
NORTH CHANNEL
1000x VERTICAL EXAGERRATION
CANARSIE
SEDIMENT SINKS
0
LESS THAN
4000’
45o
MARSHES EDGES ARE PRONE TO EROSION AND COLLAPSE AT STEEPER ANGLES, DEEP CHANNELS BECOME SEDIMENT SINKS RATHER THAN REPLENISHING MARSHES THAT SUBSIDE OVER TIME
22
SEDIMENT DEPOSITED BY HIGH TIDES
SEDIMENT DEPOSITED BY HIGH TIDES
LAND RISES UPWARD
MHHW 2050
MSL 2050
MHHW 2014
MLLW 2050 MSL 2014
MLLW 2014
23
LAND RISES UPWARD
Spartina is well adapted to the dynamic estuarine environment. The roots and the upper parts of the plant grow higher to keep from being fulling submerged. As sea levels rise with climate change, Spartina can continue to adapt well given that other required conditions are present, Spartina is the land builder of the plant world [14]. The Army Corp of Engineers (ACOE) awards dredging contracts to private companies approximately every 5 years for work within the Jamaica Bay. The ACOE directs the material management and maintenance dredging in order to maintain the Federal Navigation Channel, which is 20 feet deep at mean low water, 1000 feet wide, and about 1.7 miles long. Currently, commercial operations transport 560,683 tons through the two smaller navigation channels YELLOW BAR HASSOCK, JAMAICA BAY [17]
A DREDGE BARGE FROM THE U.S. ARMY CORPS OF ENGINEERS SPRAYS SEDIMENT INTO AN IMPOUNDED AREA IN A MARSH RESTORATION TECHNIQUE CALLED “THIN LAYERING” [18]
ELDERS POINT MARSH RESTORATION, JAMAICA BAY [19]
24
HISTORIC FILL FROM BAY DREDGE HISTORIC FILL FROM OTHER SOURCES
FEDERAL NAVIGATION CHANNEL
0’
6000’
that converge into one at Rockaway Inlet and join the Federal Channel connecting to the Atlantic Ocean. Commodities transported through the channel include petroleum and petroleum products, chemicals, sand, gravel and stone [15]. The New York City Department of Environmental Protection also operates large vessels that bring sludge from other waste water treatment facilities to one of the four treatment facilities in Jamaica Bay for dewatering [16]. The ACOE also directs a Beneficial Use of Dredged Materials Program, through which they manage the use of clean dredge material for several purposes. The Historic Area Remediation Site (HARS) is a former dumping ground for a wide variety of toxic materials deep in the Atlantic Ocean and is now being capped with clean dredge from the New York and New Jersey waterways [17]. Beach nourishment and wetland restoration in the Jamaica Bay are the two other common “beneficial” uses for this material. In 2009 approximately 480,000 cubic yards of material were removed from Jamaica Bay, with beneficial reuse both at the HARS (330,000 cubic yards) and at White Island in the Jamaica Bay (150,000 cubic yards) [15]. Outside of Jamaica Bay, dredging operations are expanding, such as in the Ambrose Channel, the route from the Atlantic Ocean to the Hudson Bay ports in New York and New Jersey. This channel is being deepened further to accommodate larger New Panamax sized cargo ships [20]. Some of the recent projects that have been completed are as follows: 2006-2007, Elders Point East 2009-2010, Elders Point West, restored approximately 80 acres of marshland. 2009-2010, Yellow Bar Hassock, approximately 45.5 acres of salt marsh via placement of ~375,000 cubic yards of sand from Ambrose Channel. 2012, Black Wall and Rulers Bar, Ambrose Channel sand for 30 acres of marsh islands at Black Wall (155,000 cubic yards of sand, 20.5 acres) and Rulers Bar (95,000 cubic yards of sand – 9.8 acres) [15] The ACOE’s own report [17] recognizes that hypoxic conditions are leading to little to no marine life in the deepest channels and borrow pits of the bay. Without addressing the underlying factors, lack of sediment input in particular, these costly efforts must continue to maintain the small acreage of salt marsh today. The ACOE describes in its report Beneficial Use of Dredged Bedrock in the New York/New Jersey Harbor (regarding the expansion of the Ambrose Channel) a variety of suggested uses for this material: artificial reefs; near shore wave attenuation breaks; groin, jetty, and revetment construction; and habitat creation and restoration through sediment resupply. These various beneficial uses are only technically possible if the correct material is used (for example, in habitat restoration-sand stone is recommended, for wave breaks, large pieces of granite). One of the greatest challenges identified in this report by the ACOE is having the ability to process out from the dredge the correct size and material type for the variety of shore line improvements [21].
26
HISTORIC
443,138 yd
3
[24]
Floyd Bennet Field is the result of an intensive period of dredging and filling in the early 20th century. It was constructed with 14 million cubic feet of fill from Jamaica Bay dredge on what was formerly known as Barren Island, an island surrounded by marsh and cut off from the mainland during high tide [15]. Initially a small fishing community, Barren Island later became the site of noxious industrial activities such as processing of dead horses and incinerating garbage. Much of the southwest corner of the land mass is garbage and byproducts of these industrial activities [22]. Beginning in 1928, residents were forced to relocate and construction began on New York City’s first municipal airport. Dozens of historic firsts in aviation were accomplished from Floyd Bennett Field and the early runways are on the historic register. During World War II the field became a military base and additional runways, barracks, and other support facilities were built. From 1945-1972 activity slowed down considerably and in 1972 the field became part of Gateway National Recreation Area [23]. Today there is a small US Marines presence as well as NYPD and NYFD training grounds, functions which create an unwelcoming atmosphere for National Park visitors particularly when combined with large expanses of former runways and roadways serve no purpose.
1928-1941 HISTORIC REGISTER BOUNDRY
0’
2000’
HISTORIC
HISTORIC
3
1,348,695 yd
1941-1945
BASED ON NPS CULTURAL LANDSCAPE REPORT [23]
3
2,053,743 yd
1945-1972
28
04 SYNTHESIS + DESIGN The goals of this design are to create a set of conditions that allow for the successful establishment of new salt marshes and the stabilization of existing marsh within the interior of Jamaica Bay given rising sea levels. This is achieved by retaining sediment in the bay through the manipulation of the tidal dynamics within the inlet. By analyzing the net velocities and bathymetry, one key conclusion could be made, where the inlet narrows, velocity increases, where it widens, the water slows. Areas of similar width but with deeper bathymetry have a slightly higher velocity but the effect is negligible in comparison to width. Two distinct design interventions are proposed, the first is to create new salt marshes within breakwater structures along the southwestern corner of Floyd Bennett Field as well as new marshes on existing land along the southern coast line of Floyd Bennett Field. The second is to add two sets of submerged breakwaters into the inlet to compensate for future sea level rise and the higher velocities that would be expected. With a higher volume of water entering the same 29
sized bay, tides will have higher energy as will larger storm surges coming into the bay through the inlet. A materials processing center would be established on the southern end of the Floyd Bennett Field where hardscape removed from the airfield would be broken down sorted, loaded onto barges, and used to build the first set of semisubmerged living breakwaters. During later phases, outside material would be accepted from dredging operations such as the Ambrose Channel and local construction projects. The materials processing center is easily accessed by both truck and boat. One of the challenges inherent in working in the Rockaway Inlet is maintaining the Navigation Channel while restoring a healthy sediment budget and marsh ecosystems. The design does not directly interfere with the Channel at its outset. Any manipulation within such a large and complex system, particularly given a changing climate, will have long term, yet unpredictable results. In order to address this uncertainty, the design includes the continued presence of the material processing center for future breakwater construction or sediment storage to adapt to future changes.
SPRING TIDES AVERAGED
Capturing and effectively analyzing a system in a state of constant movement such as an estuary or coastline can be very challenging. In order to understand the net effect of the movement through the inlet, several layers of spring and neap tide observations were layered. Understanding the relationship between velocity and particle size is key to predicting whether there will be deposition, erosion, or transport of sediment. The diagram below, based on the work of Swedish geographer Filip Hjustrom, shows what velocities (coded by color) will result in erosion, deposition, or transport of different sized particles. According to the ACOE, on the floor of the Jamaica Bay, 98% of the sediment is sand. By limiting the areas of high velocity (red to green), erosion can be avoided. The goal then is to encourage either transport or deposition (orange to purple). NEAP TIDES AVERAGED
30
Due to the scale of the bay, a traditional breakwater design of a straight line parallel to the shore line would require massive amounts of material to meaningfully changes tide velocity and potentially interfere with the Navigation Channel. The area marked ‘A’ is identified as a key area in that it is already shallow enough that breakwaters here could create small pools and eddies that support marine species such as spartina, eel grass, oysters, and mussels that requires shallow water. It is also noteworthy that this is where the high outward velocity slows after leaving the bay and therefore underwater deposition is evident. The areas marked ‘B’ and ‘C’ are also identified as promising sites for the submerged breakwaters in that they are both shallow and in predominantly high velocity areas.
SAND PARTICLES EROSION TRANSPORT DEPOSITION
31
DEPOSITION EVIDENT
A B C
NAVIGATION CHANNEL
ROADWAYS REMOVED TO CREATE MARINA BREAKS
CUT FROM SOUTH END USED TO FILL CHANNELS
2020
2025
2030
2035
2040
2045
2050
2055
2060
EXTERNAL MATERIAL ACCEPTED FOR PROCESSING
PHASE 1
OUTER BREAKS CREATED
PHASE 2
NEW MARSH PLANTED
2065
48” 42” 36” 30” 24”
RUNWAY REMOVED AND PROCESSED TO CREATE INNER BREAKS
PHASE 3
18” 12”
EXTERNAL MATERIAL ACCEPTED FOR PROCESSING OUTER BREAKS CREATED
33
PHASE 4
6” 0
MEAN SEA LEVEL
2015 PROCESSING DOCK CREATED
The design proposed would take place in four phases. Phase One involves the creation of the material processing area on an existing parking lot on the south end. This area was once a dock for sea planes to enter and exit the bay making it an ideal location for land to water transfer. The dock proposed would be wide enough to accommodate two standard barges side by side that could be loaded from either side. Once completed, the surrounding network of unused road ways would be removed, processed, and used for the first series of breakwaters closest to Floyd Bennett Field. Sediment nourishment around the breakwaters would take place so that marsh grasses could be planted. During Phase Two cuts are made into the land on the southern end of
PHASE 4
MARINA BREAKS
INNER BREAKS
OUTER BREAKS
2014
EXPANSIVE AREAS OF FORMER RUNWAY AND ROADWAYS ARE ALMOST ENTIRELY UNUSED TODAY
RUNWAY MATERIAL
35
2020
2025
MATERIAL PROCESSING CENTER
VISITOR VIEWING AREA
0’
2000’
36
Floyd Bennett Field, following the footprint of the removed roadways allowing the bay water to infiltrate (2020), the material from this process could also be used to nourish some of the deepest channels in the bay and marshes would be restored along the southeastern edge of Floyd Bennett Field. The widening of the Inlet and greater infiltration of water into these restored marshes will result in slower velocity. The first set of semi-submerged living breakwaters are oriented to extend the ebb tide to retain sediment in the Bay and also attenuate waves that may damage the newly establishing marshes at the southwest end of Floyd Bennett Field.
WATERLINE
AVIAN SPECIES NESTING AND FOOD SOURCES RECREATION HIGH AND LOW SALT MARSH EEL GRASS OYSTER AND MUSSEL BEDS FIN FISH HABITAT
Phase Three (2025) is the removal of the northernmost runway which is processed and the Inner Breaks are created. Phase Four marks the beginning of external materials being accepted so that the Outer Breaks can be constructed. The existing runways and roads can be used by the deconstruction equipment to transport material over land to the processing center. An existing road parallel to the truck route would allow visitors to enter the area and observe the activity from a safe distance.
SAND AND SILT FOR MARSH RESTORATION GRAVEL AND CONCRETE FOR BREAKWATERS
37
ROCKAWAY PENINSULA MATERIAL FOR INNER BREAKS
SALT MARSH
MUD FLATS
VIEW FROM MARINA BREAKS, LOOKING SOUTHWEST
JFK AIRPORT
REPURPOSED RUNWAY
VIEW OF MATERIALS PROCESSING CENTER, LOOKING EAST
PHASE 1-2: MARINA BREAKS
2015
ROCKAWAY PENNISULA
EBB TIDE SLOWED
NAVIGATION CHANNEL
LIVING BREAKWATERS
FLOYD BENNETT FIELD
Phase 1 begins with the creation of the material processing area at the south end of Floyd Bennett Field. Former concrete roadways surrounding the dock are used to form the first set of living breakwaters, these are curved toward the inner bay to increase the ebb tide. These also serve to protect the newly created marsh (Phase 2) on the southeast corner from tidal erosion by reducing the tide’s energy. In addition to the restored southeast marshes, the breakwaters are designed to create many eddies and small pools where additional marsh and oyster or mussel ecology can take hold.
LIVING BREAKWATERS PROTECT INNER MARSH AREA FROM STRONG FLOOD TIDE ENERGY
2020
MARSH AND HARD MATERIAL REDUCE FLOOD TIDE ENERGY 0’
39
500’
ROCKAWAY PENNISULA
EBB TIDE LENGTH EXTENDED OVER TIME
NAVIGATION CHANNEL
MARSH ECOLOGY RESTORED
LIVING BREAKWATERS
FLOYD BENNETT FIELD
0’
500’
0’
2000’
PHASE 3: INNER BREAKS
ROCKAWAY PENNISULA
SECOND DEFENSE ASSIST WITH INCREASING EBB TIDE
NAVIGATION CHANNEL
SUBMERGED BREAKWATER
The Phase Three Inner Breaks are begun in 2020 and are completed by 2030. High estimates put sea level rise at 12” above today’s level by 2030. With higher sea levels come larger volumes of water and higher velocities. The Inner Breaks are completely submerged and curve toward the inner bay in order to bolster the existing breakwaters and further lengthen the ebb tide.
STRONG FLOOD TIDE ENERGY
2020
2030 41
1000’
ROCKAWAY PENNISULA
VOLUME OF WATER AND VELOCITY INCREASES WITH SLR
NAVIGATION CHANNEL
SUBMERGED BREAKWATER
0’
+12” SLR
FLOOD TIDE ENERGY INCREASES WITH HIGHER SEA LEVELS 0’
1000’
0’
2000’
PHASE 4: OUTER BREAKS
2030
ROCKAWAY PENNISULA
EBB AND FLOOD TIDE EQUALIZED
NAVIGATION CHANNEL
SUBMERGED BREAKWATER
The Phase Four Outer Breaks are also completely submerged but are curved away from the inner bay. The assumption being made is that by 2030 the sediment budget and marsh health has increased to the point that equalization between effects on the flood and ebb tide is desirable but the need to slow velocities overall has only increased with sea level rise. This is highly speculative and would need to be addressed after observed results in the field.
1000’
ROCKAWAY PENNISULA
EBB AND FLOOD TIDE EQUALIZED BUT STRONGER OVER TIME
NAVIGATION CHANNEL
SUBMERGED BREAKWATER
0’
+31” SLR
2050 0’
43
1000’
0’
4000’
PHASE 2-3
The phases of work, the processes involved of deconstructing and constructing, occur simultaneously. The mode applied in the making of this landscape is one of continuous adaptation and reevaluation.
MARINA BREAKS AND MARSH
45
TRUCKING ROUTE
TRUCKING ROUTE PHASE 4 TRUCKING ROUTE NEW MARSHES
OBSERVATION AREA PROCESSING DOCK
FILL TO REPAIR PREVIOUSLY DREDGED CHANNELS MATERIAL FOR INNER BREAKS
05 DESIGN ANALYSIS As velocity was a guiding force in the conception of this design, it is only fitting to use it as a measure its effectiveness. In the first scenario shown to the right, Phase One and Two are complete and the velocities demonstrated are for a spring ebb tide in the year 2030. The results are entirely the fabrication of the author though accuracy has been attempted. As the water leaves the bay it first encounters the marsh islands which slow it down as do the Inner Breaks. The pull of the tide ocean-ward would increase the velocity on either side of the Inner Breaks. The inlet side of the Rockaway Peninsula would likely be subject to erosion and would require addressing. In Scenario Two (following page), the year is 2050 and Phase Three is complete. The Outer Breaks are in place and the marsh islands have expanded further. The incoming water will be of highest velocity and will meet the breaks curved against its force. This will presumably slow the water down considerably but may mean that the Outer Breaks will be unable to withstand the force and be compromised. The water enters a wider area and hits the Inner Breaks, quickly 47
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followed by the marsh island. A similar issue could be caused in this scenario where the inlet facing side of Rockaway Peninsula becomes vulnerable to strong erosive forces. With predicted sea level rise by this time, much of Rockaway Peninsula would be under constant threat of flooding and it is possible that counter measures like dikes will have been installed that would protect against erosive forces.
SCENARIO 1 SPRING EBB TIDE 2030
One solution that could also be explored is a more dramatic widening of the Inlet. There are two obstacles to this that made it impractical, one is a large polluted area of landfill at the southeast corner where the living breakwaters are proposed. Rather than disturb the soil, I chose to keep it in place and protect it from erosion with additional material. The second constraint is the presence of the Gil Hodges bridge crossing the inlet, it is an evacuation route for the residents of Rockaway Peninsula and the approach therefore needs to stay in place. Given that this bridge is classified as functionally obsolete, another possible scenario would be to use the landfill area for a replacement bridge approach thereby allowing for a more dramatic widening of the inlet. In all possible scenarios there are compromises that must be accepted. With this design I attempted to balance the existing conditions and current uses with an attempt to restore marine ecosystems at a large scale. The tidal energy may be blocked in one area only to hit another with more force, for example. The nature of coastal areas is that they are a fluid system and as long as there are settlements and 49
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hard edges built into these places compromises will have to be made. The industrial uses that bring the danger of toxic spills and require continued maintenance dredging of the navigation channels are directly at odd with the purpose of a National Park and a wildlife refuge. For most of its history Jamaica Bay has contributed significantly to the health of New York City, whether by providing oysters, cleaning the water in its marshes, or recreation. If the bay is to continue to provide the many ecological services it has in the past, some difficult compromised may have to be accepted.
SCENARIO 2 SPRING FLOOD TIDE 2050
REFERENCES
[1] Based on high end projection by Climate Central in their report, “New York And The Surging Sea: A Vulnerability Assessment With Projections For Sea Level Rise And Coastal Flood Risk”. climatecentral.org. [2] Maxfield, J., Hurricane Sandy, One Year Later: Assessing the Economic Cost. Daily Finance. October 26, 2013. Retrieved from : http:// www.dailyfinance.com/on/hurricane-sandy-anniversary-economic-cost/ [3] Editorial. Hurricane Sandy’s Rising Costs. New York Times. November 27, 2012. Retrieved from: http://www.nytimes.com/2012/11/28/ opinion/hurricane-sandys-rising-costs.html?_r=0 [4] New York City Parks Department, Jamaica Bay. Retrieved from: http://www.nycgovparks.org/parks/jamaicabay [5] New York City Audobon, Jamaica Bay Project. Retrieved from: http://www.nycaudubon.org/jamaica-bay-project [6] Photo by Mario Tama/Getty Images. [7] National Park Service, 2010, Coastal Geomorphology of the Ocean Shoreline, Gateway National Recreation Area Natural Evolution and Cultural Modifications, a Synthesis Natural Resource Report. [8] Hartig, E., Gornitz, V., December 2001. The Vanishing Marshes of Jamaica Bay: Sea Level Rise or Environmental Degradation? Retrived from: http://www.giss.nasa.gov/research/briefs/hartig_01/ [9] National Oceanic and Atmospheric Administration (NOAA), Soundings Maps. Retrieved from: http://historicalcharts.noaa.gov/ [10] NOAA tide predictions for March 2014 at Sandy Hook, NJ and adjusted for Rockaway Inlet, NY, http://tidesandcurrents.noaa.gov/noaatidepredictions/NOAATidesFacade.jsp?Stationid=8531680 [10] Based on images made available from Stevens Institute of Technology’s maritime forecast website. Images were selected from hourly maps that coincided as closely as possible with measured high and low tides during two full day’s cycle, March 1, 2014 for Spring tides and March 8, 2014 for Neap tides. http://hudson.dl.stevens-tech.edu/maritimeforecast/maincontrol.shtml [11] French, Peter W., Coastal and Estuarine Management. London: Routledge, 1997. [12] Impervious surfaces based on map made available by Jamaica Bay Research and Management Information Network. http://www.ciesin. org/jamaicabay/maps.jsp. Historic creeks gleaned from USGS 1898 topographic survey. [13] United States Geological Survey, topographic maps, http://www.usgs.gov/pubprod/maps.html [14] Chabreck, Robert H. Coastal Marshes: Ecology and Wildlife Management. Minneapolis: University of Minnesota Press, 1988. [15] United States Army Corp of Engineers, Fact Sheet, Jamaica Bay-New York-Federal Navigation Channel. Retrieved from: http://www.nan.
usace.army.mil/Media/FactSheets/FactSheetArticleView/tabid/11241/Article/10268/fact-sheet-jamaica-bay-marsh-islands.aspx [16] New York Water Environment Association, Marine Vessels Serving New York City. Retrieved from: http://nywea.org/clearwaters/pre02fall/312010. html [17] Unattribued photo from Dredging Today, Retrieved from: http://www.dredgingtoday.com/2012/01/19/army-corps-awards-contracts-for-yellowbar-hassock-marsh-island-restoration-usa/ [18] Photo credit, US Army Corp of Engineers, A dredge barge from the U.S. Army Corps of Engineers sprays sediment into an impounded area in a a marsh restoration technique called “thin layering.� Once the sediment builds-up the substrate, marsh plants are added to secure it and rebuild the marsh. [19] Frank Koester For New York Daily News, Tuesday, April 16, 2013. The Elders Point Marsh Island in Jamaica Bay. [20] Holmes, R., Milligan, B., Designing the Dredge Cycle, Scenario Journal, Spring 2013. Retrieved from:http://scenariojournal.com/article/feedbackdesigning-the-dredge-cycle/ [21] United States Army Corp of Engineers, Dredging Operations Technical Support Program, Beneficial Use of Dredged Bedrock in the New York/New Jersey Harbor, July 2003 [22] Hendrick, Daniel M. Jamaica Bay. Charleston, SC: Arcadia Pub., 2006. [23] National Park Service, Cultural Landscape Report For Floyd Bennett Field Gateway National Recreation Area,Site History, Existing Conditions, Analysis And Evaluation. 2009. Retrieved from: http://www.nps.gov/history/history/online_books/gate/floyd_bennett_clr.pdf [24] Photo by user stevenhenderso, from flikr.com. [25] Final image on following pages, 1931 Aerial of Floyd Bennett Field under construction, copyright New York Public Library