New York Harbor Storm-Surge Barrier

The New York Harbor Storm-Surge Barrier is a proposed barrier and floodgate system to protect the New York-New Jersey Harbor Estuary from storm surges. The proposed system would consist of one barrier located across the mouth of Lower New York Bay between Sandy Hook (N.J.) and Rockaway (N.Y.) and a second on the upper East River to provide a ring of protection to most of the bi-state region. Through extensive use of floodgates, both barriers would have largely open cross-sections during normal conditions to minimize environmental impacts on the estuary and port operations.[1][2]

Map of proposed storm surge barrier locations around New York Harbor.

To address the problem of sea level rise, smaller scale projects to increase seawall heights or otherwise raise vulnerable coastlines would be necessary. Thus a storm-surge barrier system combined with coastline adjustments would form a two-tiered strategy to protect the region. The barrier system could also be extended eastward, filling in the gaps between barrier islands, to protect the various communities lining the south shore of Long Island.[3]

External media
Images
image icon View of potential surge barrier locations in Google Earth.
image icon Detail of the proposed Outer Harbor Barrier.
image icon Map Showing barriers and areas protected.
Video
video icon Video animation of a proposed Outer Harbor Barrier in operation (4:11).
video icon Video animation of a more open design (0.30).

The proposal was developed in the wake of Hurricane Sandy by the Metropolitan NY-NJ-LI Storm Surge Working Group (SSWG), composed of prominent entrepreneurs, civic leaders, social scientists, oceanographers, marine ecologists, meteorologists, engineers, architects, economists, attorneys and media experts. The group is chaired by Malcolm Bowman, a professor of physical oceanography at the State University of New York at Stony Brook.[4][5] Within the barrier system lies crucial infrastructure such as the seaports and maritime facilities; ground level and underground transportation terminals; three major international airports; subway and roadway tunnels; hospitals; communication centers; the industrial complex of northern New Jersey; as well as the millions of residents at risk in New York City and coastal New Jersey north of Sandy Hook.[6][7]

NeedEdit

The New York-New Jersey Harbor is vulnerable to storm surges that threaten to inundate the region, put in danger large numbers of the metropolitan area's residents, devastate much critical infrastructure and damage some of its most important economic assets. At particular risk are the most vulnerable, low-income communities located in many public housing projects located on low-lying land near to the coast.[8]

The source of energy for all hurricanes is the elevated temperatures of the tropical Atlantic Ocean and the associated warm surface temperatures of the Gulf Stream flowing northwards along the eastern seaboard. Accordingly, hurricanes are most dangerous when their track lies slightly offshore.[9]

 
Sandy 2012 track

Hurricane Sandy's power came from unusually warm water lying off the mid-Atlantic Coast and the merging of two major storm systems. Technically, Sandy was downgraded from a category one hurricane to an extra-tropical storm just before it made landfall in New Jersey on October 29, 2012. Nevertheless, as the largest storm in extent ever recorded by the National Weather Service (at 1100 miles in diameter), Sandy's storm-surge impacts on New York and New Jersey were severe.[8]

Because of global warming, oceanographic and meteorological experts currently predict that increasingly warmer future ocean surface temperature is the "new normal", implying that extreme weather events like Hurricanes Sandy and Maria could become more intense and possibly more frequent during future hurricane seasons. As the world's oceans steadily become warmer; storms are becoming stronger and larger. These storms will cause more damage if they follow past storm tracks.[9][10] For example, research suggests that hurricanes that have hit the New York City area since 1970 are more intense or have larger wind fields, producing higher storm surge and flood risk. When added to rising sea level, what was a 500-year flood event before the anthropogenic era (i.e. pre-1800) is now a 24-year flood event[11] and in 30 years will be a 5-year flood event.[12][13]

The risks to the New York Metropolitan Region also include wind and flooding damage from winter nor’easter storms which can be as serious, or even more dangerous, than rarer hurricanes. While hurricanes are short and violent, nor’easters tend to persist longer — for several days — also producing large storm surges that ride atop successive high tides that occur twice daily.[8]

Adding to storm surge risks, sea levels are also rising. Over the last 160 years the National Oceanic and Atmospheric Administration's (NOAA's) Battery Park tide gauge has measured the rate of sea-level rise as one foot per century.[14] But sea level rise is expected to accelerate, adding an additional 3–6 feet to current sea level by the end of this century, or possibly more if the melting of the Greenland ice sheet continues at ever increasing rates and huge chunks of ice around Antarctica continue to break off.[9][12][15][16][17][18]

PrecedentsEdit

 
Maeslant Barrier, the Netherlands

Similar, albeit more modestly-sized, but still highly effective storm-surge barriers have been in operation for nearly half a century in three New England communities — the Stamford Hurricane Protection Barrier in Stamford, Conn.; the Fox Point Hurricane Barrier in Providence, R.I.; and the New Bedford Harbor Hurricane Barrier[19] in New Bedford, Mass. Hours before Hurricane Sandy struck Stamford, the city's 17-foot-high movable barrier was closed to withstand an over-11-foot storm tide which struck western Long Island Sound (at some locations on the sound, the storm tide was even higher than the 11.5-foot storm tide measured at The Battery in New York City), devastating every waterfront community on the northwestern coast of the sound — except Stamford.[20][21]

Larger barrier systems protect more than a dozen major cities, including the Delta Works protecting the south of the Netherlands and the MOSE Project protecting Venice. New storm-surge barriers on Lake Borgne and Lake Pontchartrain are part of the protection for New Orleans after Hurricane Katrina.

The famous Thames Barrier is typically deployed up to 12 times per year, protecting the heart of London from flood devastation. The Greater London Authority is currently studying proposals to strengthen its defenses.

 
Flooding in St. Petersburg, Russia during the 1824 flood

The new Saint Petersburg Dam was built to stop the frequent floods in the city, which had often devastated the city. It was first used on November 28, 2011, just months after it was completed, and limited sea water rise to below flood level.[22] It prevented the 309th flood in the history of the city.[23]

BackgroundEdit

Well before Hurricane Sandy struck Metropolitan New York in October 2012, experts were warning that a major storm could cause significant flooding and damage.[24] With funding from the Rockefeller Foundation, Mayor Michael Bloomberg, convened the New York City Panel on Climate Change in August 2008 to investigate the city's vulnerability to a variety of climate-induced risks including the risk of a major storm-surge event. At about the same time, the American Society of Civil Engineers organized a three-day conference and subsequently published a report entitled "Storm-Surge Barriers to Protect New York City Against the Deluge."[25][26][27]

After Hurricane Sandy devastated the New York - New Jersey metropolitan area in 2012, governments struggled both to recover and to plan better protection for the future, including regional storm-surge barriers. In his January 2013, State of the State address,[28] New York Governor Andrew Cuomo proposed to "work with other government partners to timely complete a comprehensive engineering evaluation of these potential barrier systems."

The City of New York, under Mayor Michael Bloomberg, organized a "Special Initiative for Rebuilding and Resiliency" (SIRR), which developed a blueprint for reconstruction that was released in June 2013, only eight months after the storm. That over-400-page document describes the demographics and morphology of the region, the storm and its impacts; provides background on extreme weather events including non-storm events such as heat and intense rainfall; describes various resiliency measures and strategies; and describes specific initiatives, studies and projects to be undertaken.[8] Some of these projects are underway, using a combination of federal and local funds.[29][30][31][32][33]

City and regional responseEdit

Despite Governor Cuomo's announced interest in storm surge barriers, Mayor Bloomberg was reluctant to proceed.[34][35][36] But the City asked Dr. Jeroen Aerts, a professor of water and climate risk with the VU University of Amsterdam, the Netherlands, and an expert on water risk management, to compare the costs and benefits of a regional barrier system with those of smaller-scale changes like building levees around sewage treatment plants, raising subway stations entrances, constructing local storm-surge barriers, and flood-proofing or raising buildings according to the FEMA-run National Flood Insurance Program standards.[20][37][38] At the same time FEMA intends to redraw flood maps for New York City, placing a much larger area in the flood zone.[39]

Dr. Aerts' report indicated that, assuming a middle scenario for climate change, which includes the combined effect of sea-level rise and increased storm activity, the benefit/cost ratio of investment in a regional barrier would be similar to the ratio for investment in smaller-scale changes.[40] Despite that result, the city's SIRR report dismissed the regional barrier idea without any further study. The report listed seven reasons for doubt about the feasibility:[8]

  1. Such a system of barriers would be extraordinarily expensive — perhaps costing $20–25 billion to build.
  2. Harbor-wide barriers would require a design, approval and construction process that could take two to three decades to complete.
  3. The possible hydrodynamic and environmental impacts on fish migration, siltation, river flow, and water quality are likely to be substantial and are not yet known.
  4. To make the project work, massive levees along adjacent coastal areas, including on the Rockaway Peninsula and possibly Coney Island and Staten Island would have dramatic impacts on the character of the beaches and adjacent neighborhoods that may prove to be highly disruptive.
  5. Any barriers would create an “insiders/outsiders” dynamic, with only those behind the barriers receiving maximum protection, leaving densely developed communities along the South and North Shores of Long Island and the Jersey Shore outside the protected zone.
  6. A harborwide barrier project may also cause additional flooding in areas outside the barriers, making those communities more vulnerable than they would be without such barriers.
  7. Finally, since the barriers would be open most of the time (to allow navigation), it would represent a major public investment that would end up doing nothing to address the growing problem of rising sea level.
External media
Images
  Map showing SIRR Phase 1 coastal protection plan.
  Map showing SIRR full coastal protection plan.
Video
  PBS News Hour segment on Dutch lessons for protecting New York Harbor, Oct 29, 2013 (8:39).
  PBS News Hour segment on situation five years after Hurricane Sandy, October 30, 2017 (10:09).

Instead of a barrier system, the SIRR report identified a plethora of local measures that could be taken by the city. The goal of these measures is to protect vulnerable areas of the city with projects that would be relatively inexpensive, effective and quickly designed and constructed. They include local walls or barriers against storm surge on some sections of the coast.[8][41] For example, a barrier has been funded as part of an inner defensive ring for Lower Manhattan,[42] to be integrated into the Manhattan Waterfront Greenway.

At the same time that the city was implementing its own local flood mitigation strategy, the MTA, Port Authority of New York and New Jersey and many major institutions and private companies adopted their own localized plans for their facilities. Hoboken and other cities in the region have initiated their own local measures,[43][44] with support from the U.S. Department of Housing and Urban Development's Rebuild by Design competition.[45] The U.S. Army Corps of Engineers has conducted coastal storm risk reduction studies and beach restoration and resiliency projects.[46][47]

Because of the variety of governmental entities involved, as well as differing community reaction, there is a lack of coordination on goals and standards of storm protection among the various projects. As a result, these scattered efforts have proved to be more difficult to execute, as well as more expensive than expected, and raise doubt about how much of the shoreline will be protected in the end.[48][49][50]

CounterargumentsEdit

Lost in all this activity is the conclusion of Dr. Aerts' study — that because of the expectation of rising sea level and increased global warming, by 2040 the benefit/cost ratio of a regional barrier system will far exceed the ratio for the measures the city is now taking, that a regional barrier may be needed soon, and that planning for it should begin now.[40] "As a Dutchman," Dr. Aerts said, "you are quite surprised íto see a large city like New York — so many people exposed and no levees, no protection at all. [That] was astonishing to me. . . . Don't rule out yet the barriers because the sea level is going to rise very quickly and you need a barrier."[51][52]

The Storm-Surge Working Group has provided answers to all the objections raised by the city.[53]

  1. A barrier system would be expensive, but the city's plan, covering many miles of vulnerable coastline, would be even more expensive. And some of the cost to shore up areas on the sides of the barriers are scheduled to be spent anyway, for example in dune-building projects on the Rockaway peninsula.[40][46]
  2. If a barrier takes a long time to implement, so do local projects. Almost nine years since Sandy struck, local projects have yet to be completed and have experienced the same problems (costs, public resistance, etc.) that were attributed to the regional storm surge barrier approach.[53]
  3. With regard to environmental impacts, the barriers' floodgates would be closed only for a few hours before, during and immediately after a major storm surge. Over 99% of the time, floodgates would remain open so as to minimally hinder tides, harbor flushing, river discharge, fish migration and healthy marine ecosystem functioning. An environmental impact study would evaluate whether any hindrance posed by the structure is outweighed by its benefit. Preliminary studies sponsored by the Hudson River Foundation indicate that an outer harbor barrier would minimally decrease tidal flow as long as floodgates allow at least 60% of the barrier cross section to be normally-open.[54] Even that small decrease merely offsets the equally small increase in tidal flow that resulted from digging shipping channels into the harbor over the past 150 years.[55]
  4. Levees will indeed have to be built in the Rockaways and Sandy Hook, but not around Coney Island, Staten Island and northern New Jersey, since they are all within the perimeter of protection of the Outer Harbor Gateway. In the Rockaways and Sandy Hook, levee design will be less difficult that for the SIRR projects with respect to protecting dense urban communities but minimizing disruption of existing water views and access.[53]
  5. Because of the immense lengths of the New York Bight and Atlantic shorelines (Montauk Point, N.Y. to Cape May, N.J.), research has shown that ocean water displaced by the barrier system would only increase coastal surges adjacent to the barrier by a few inches on the ocean and western Long Island Sound sides.[53]
  6. While ocean shore communities outside the region would not be protected by two barriers around New York Harbor, it would be possible to extend the area to be protected by constructing barriers in gaps between barrier islands along the south shore of Long Island, and south along the Jersey shore, or with barriers oriented perpendicular to the barrier islands, depending on the dominant direction of hurricane winds.[53][56][57]
  7. With normally-open storm-surge gates, barriers alone will not address sea level rise, but neither will local shoreline storm-surge projects planned by New York City, which will also have gates. The SIRR report, itself, found that by the 2050s 43 miles, or about 8%, of the city's coastline could be at risk of flooding during non-storm conditions. These coastal areas will need to be raised or otherwise protected regardless of additional protections against storm surge.[8]
External images
  Map showing areas vulnerable to sea-level rise
  Map showing housing units vulnerable to sea-level rise.

The two-tiered approach of protecting local coastal areas against slowly changing sea level rise, together with 25-foot offshore barriers to hold back surges of future storms, will give future civic leaders 100 to 150 years to protect, and if necessary migrate, our urban metropolitan civilization to higher ground, and to adopt even more sweeping measures to protect the region from both sea level rise and storm surges.[53]

Another objection to barriers is that restored natural systems, such as created wetlands and oyster beds could provide the same protection. While these proposed solutions should be included in local responses because they can reduce wave action slightly, reinforce presently fragile wetlands and in some cases improve water quality, the reality is that they would be simply overwhelmed by storm surges of the magnitude experienced during Sandy. One naturalistic feature can resist storm-surge—levees or dunes. In fact most of the coastline of the Netherlands is protected in this way.[53] A regional storm surge barrier would depend on dunes along the coast of the Rockaway Peninsula and Sandy Hook.

Army Corps of Engineers studyEdit

In the Fall of 2017, the Army Corps of Engineers initiated a Coastal Storm Risk Management Feasibility Study[58] to evaluate various proposals to address storm surge in the New York and New Jersey harbor area. The New York Harbor Storm-Surge Barrier, modified to increase permeability, is one of five alternatives being considered.

To solicit comments on the scope of the study, the Corps has released a fact sheet,[59] a presentation for scoping meetings,[60] and scoping meeting posters.[61]

The schedule for the study is as follows:

Scoping Period through November 5, 2018
Release of the Draft Interim Report Feb. 2019
Delay due to funding suspension Feb. 2020 – Sept. 2021
Tentatively Selected Plan May 2022
Draft Feasibility Report and Tier 1 EIS July 2022
Agency Reviews and Public Meetings Aug–Sept 2022
Optimization of the Selected Plan
Final Feasibility Report and NEPA Documentation January 2023
Chief's Report Summer 2024
Pre-Construction Engineering and Design Phase & Tier 2 EIS

The Interim Report[62] is posted on the USACE website,[63] along with six appendices. Subsequently, the USACE presented updated cost information and additional studies.[64][65]

In December, 2020, Congress instructed the USACE to expedite the study,[66] after the Corps had "indefinitely postponed" the project the previous February.[2] According to the project website,[63] the Corps is currently looking for funds to restart the HATS study.

See alsoEdit

ReferencesEdit

  1. ^ Barnard, Anne (January 17, 2020). "The $119 Billion Sea Wall That Could Defend New York … or Not". The New York Times.
  2. ^ a b Barnard, Anne (February 25, 2020). "After Trump Mocks a Sea Wall in New York, Plan Is Abruptly Shelved". The New York Times. ISSN 0362-4331. Retrieved February 27, 2020.
  3. ^ View of Potential Surge Barrier Locations in Google Earth.
  4. ^ Malcolm Bowman's biography.
  5. ^ Patrick McGeehan, Making a Pitch, Again, for Barriers to Block Storm Surges," New York Times, October 11, 2017.
  6. ^ Detail of the Outer Harbor Barrier
  7. ^ Henry Goldman, "New York City Planners With Sandy Nightmares Say Barrier May Come Too Late," Bloomberg News, June 20, 2017.
  8. ^ a b c d e f g City of New York, "PlaNYC, A Stronger, More Resilient New York", June 11, 2013.
  9. ^ a b c New York Academy of Sciences, "New York City Panel on Climate Change 2015 Report", Ann. N.Y. Acad. Sci. ISSN 0077-8923, January 2015.
  10. ^ Lin, et al., "Hurricane Sandy's flood frequency increasing from year 1800 to 2100,", PNAS 113 (43) 12071.
  11. ^ Andra J. Reed, et al., "Increased threat of tropical cyclones and coastal flooding to New York City during the anthropogenic era,", PNAS 112 (41) 12610-12615, October 28, 2015.
  12. ^ a b Andra J. Garner, et al., "Impact of climate change on New York City's coastal flood hazard: Increasing flood heights from the preindustrial to 2300 CE,", PNAS 114 (45) 11861, November 7, 2017.
  13. ^ Stefan Rahmstorf, "Rising hazard of storm-surge flooding," PNAS, 114 (45) 11806-11808, November 7, 2017.
  14. ^ NOAA, Battery Park Mean Sea Level Trend.
  15. ^ James Hanson, "Why I Must Speak Out about Climate Change," TED Talk, 2012.
  16. ^ Damian Carrington, "Sea levels set to 'rise far more rapidly than expected.'" The Guardian, March 30, 2016.
  17. ^ Don Jergler, "RIMS 2016: Sea Level Rise Will Be Worse and Come Sooner," Insurance Journal, April 12, 2017.
  18. ^ David Wallace-Wells, "The Uninhabitable Earth: Famine, economic collapse, a sun that cooks us: What climate change could wreak — sooner than you think," New York Magazine, July 9, 2017.
  19. ^ U.S. Army Corps of Engineers, "New Bedford Hurricane Protection Barrier".
  20. ^ a b Mireya Navarro, New York Times, "Weighing Sea Barriers as Protection for New York", November 7, 2012.
  21. ^ Andrew Morang, "Hurricane Barriers in New England and New Jersey: History and Status after Five Decades," Journal of Coastal Research, 32 181–205 (2016).
  22. ^ (in Russian) Мощнейший ураган и наводнение накрыли Петербург: вода угрожает городу (ВИДЕО), Главред, November 28, 2011
  23. ^ Дирекция КЗС: Дамба предотвратила ущерб в 1,3 млрд рублей (in Russian)
  24. ^ Samuel Gofseyeff and Frank L. Panuzio, Hurricane Studies of New York Harbor, Transactions of the American Society of Civil Engineers, 1963, Vol. 128, Issue 4, pp. 394-420.
  25. ^ Malcolm J. Bowman, "A City at Sea," New York Times, September 25, 2005.
  26. ^ D. Hill. M.J. Bowman, J.S. Khinda, "Storm Surge Barriers to Protect New York City: Against the Deluge,” 2012.
  27. ^ James Glanz and Mireya Navarro, "Engineers’ Warnings in 2009 Detailed Storm Surge Threat to the Region," New York Times, November 4, 2012.
  28. ^ Governor Andrew Cuomo, "NY RISING: 2013 State of the State", October 29, 2012.
  29. ^ Lisa W. Foderaro, "In Rockaways Infusion of Sand Will Soon Raise Beaches Hit by Hurricane Sandy," New York Times, February 28, 2014.
  30. ^ Nathan Kensinger, "Four years after Sandy, Staten Island's shoreline is transformed," Curbed, October 27, 2016.
  31. ^ Nathan Kensinger, "Climate change in Trump's NYC: How at-risk neighborhoods are combating rising sea levels," Curbed, January 26, 2017.
  32. ^ Nathan Kensinger, "A long-neglected Queens neighborhood grapples with the effects of climate change in NYC," Curbed, April 13, 2017.
  33. ^ Luis FERRÉ-SADURNÍ, "Could the Rockaways Survive Another Sandy?" New York Times, July 13, 2007.
  34. ^ Joe Nocera, "Mayor Bloomberg's Barrier," New York Times, November 3, 2012.
  35. ^ ABC News, "Sandy Spurs Talk of Sea Barrier for New York," November 2, 2012
  36. ^ WCBS, Bloomberg on Storm Barrier Idea: Not in Your Lifetime." March 5, 2013.
  37. ^ David W. Dunlap, "A Guide to Flood-Resistant Building," New York Times, January 25, 2017.
  38. ^ Brooke Jarvis, "When Rising Seas Transform Risk Into Certainty," New York Times, April 18, 2017.
  39. ^ David W. Chen, "In New York, Drawing Flood Maps Is a 'Game of Inches'," New York Times,January 7, 2018.
  40. ^ a b c Jeroen Aerts, et al., "Evaluating Flood Resilience Strategies for Coastal Megacities", Science, 344:473, May 2, 2014.
  41. ^ David W. Dunlap, "Building to the Sky, With a Plan for Rising Waters," New York Times, January 26, 2017.
  42. ^ "Lower Manhattan flood barrier gets $176M in fed funds". NY Daily News. Retrieved August 14, 2017.
  43. ^ Patrick McGeehan, "Plan to Flood-Proof Hoboken Runs into a Wall," New York Times, February 7, 2016.
  44. ^ Ford Fessenden and Jeremy White, "Hoboken Flood Wall Maps," New York Times, February 7, 2016.
  45. ^ Kia Gregory, "HUD Storm Protection Competition Will Narrow Ideas Big and Small," New York Times, November 14, 2013.
  46. ^ a b U.S. Army Corps of Engineers. "NY District Coastal Storm Risk Reduction Projects and Studies Map". Retrieved April 19, 2017.
  47. ^ Mireya Navarro and Rachel Nuwer, "Resisted for Blocking the View, Dunes Prove They Blunt Storms," New York Times, December 12, 2012
  48. ^ Marc Santora, "Scientists Glimpse New York's Perilous Path in an Ancient Patch of Marsh," New York Times, January 19, 2017.
  49. ^ Justin Davidson, "Sea Levels Might Be Rising Much Faster Than Expected. What Should New York Do to Avoid Being Swamped?," New York Magazine, July 23, 2015.
  50. ^ Josh Robbin, "Five Years After Sandy: Blown Deadlines," NY1, October 25, 2017.
  51. ^ PBS News Hour segment on Dutch lessons for protecting New York Harbor, Oct 29, 2013 (8:39).
  52. ^ Michael Kimmelman, The Dutch Have Solutions to Rising Seas. The World Is Watching." New York Times, June 15, 2017.
  53. ^ a b c d e f g Storm-Surge Working Group, "Protecting the NY-NJ Metropolitan Region from The Next Disastrous Storm Surge: Summary Report," March 9, 2017.
  54. ^ Philip M. Orton and David K. Ralston, ""Preliminary Evaluation of the Physical Influences of Storm Surge Barriers on the Hudson River Estuary," September 2018.
  55. ^ David Ralston, et al., "Bigger tides, less flooding: Effects of dredging on barotropic dynamics in a highly modified estuary," J. Geophys. Res., 124, 196-211 (2019).
  56. ^ USACE, New Jersey Back Bays Study, 2021.
  57. ^ USACE, Nassau County Back Bays Study, 2021.
  58. ^ Coastal Storm Risk Management Feasibility Study
  59. ^ USACE HATS Fact Sheet
  60. ^ USACE HATS Presentation for Scoping Meetings
  61. ^ USACE HATS Scoping Meeting Posters
  62. ^ USACE HATS Interim Report
  63. ^ a b USACE Project Website
  64. ^ USACE Updated Cost Information
  65. ^ USACE Additional studies
  66. ^ Waterfront Alliance Press Release

External linksEdit