ACOE plan for storm protection focusing on the communities around Jamaica Bay

1. COASTAL STORM RISK
MANAGEMENT
ALTERNATIVE
FORMULATION FOR
JAMAICA BAY
COMMUNITIES
JAMAICA BAY TASK FORCE MEETING
November 1, 2018
Peter Weppler, Chief
Environmental Analysis Branch
Planning Division
New York District
U.S. Army Corps of Engineers
Jamaica Bay, facing South from Brooklyn towards the
Bay, Rockaway Peninsula, and Atlantic Ocean. Source:
Boating Times Long Island, Photo by Jim Mobel
Jamaica Bay, New York City

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CORPS OF ENGINEERS
PLAN FORMULATION PROCESS
• Identify problems and opportunities
• Inventory and forecast conditions
• Formulate alternatives to manage the risk of flooding from
coastal storms
• Evaluate alternatives
o Plans are screened for completeness, effectiveness, efficiency, and acceptability
o Compare reduced damages of proposed alternatives against without project conditions
to determine benefits
o Perform an initial evaluation of environmental impacts
o Compare benefits to costs for each alternative
 To be economically justified a plan must have a benefit-to-cost ratio (BCR)
greater than one
• Compare alternatives
• Select alternative

3. ADDRESSING SEA LEVEL RISE
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• Adapting to sea level rise is NOT optional and it is a
shared responsibility.
• Incorporates the most recent, sound science analyses of
how to adapt coastal storm risk measures to increased
future sea level in their design and analyses.
• This includes assessing risk and uncertainty based on an
uncertain future.

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EAST ROCKAWAY INLET TO ROCKAWAY INLET AND
JAMAICA BAY – ROCKAWAY BEACH

5. BACKGROUND ON ROCKAWAY REFORMULATION
Draft Report Released August 2016  wide-ranging public and agency
comments were received
Tentatively Selected Plan in the 2016 Draft Report recommended a
comprehensive $3B plan (which has since been revised) but included:
Storm surge barrier across Jamaica Bay inlet
Atlantic Shorefront seawall dune and beach system with groin
enhancement
Smaller features in the Back-Bay to manage risk for frequent flooding
when the barrier would remain open
The $5B “perimeter plan” of floodwalls and tributary gates around
Jamaica Bay was screened out in favor of the above
Public and Agency Input called for further analysis of proposed storm surge
barrier across Jamaica Bay
Numerous comments requested the inclusion of additional natural and
nature-based features (NNBFs) in Jamaica Bay
Equally, there were many comments requesting that the study be expedited
to construct the Atlantic Shorefront feature earlier than proposed
Draft Revise Report Released August 2018.
Comment period closed October 22, 2018
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6. RECOMMENDED PLAN
ATLANTIC SHOREFRONT REACH
• Reinforced
vegetated dune
and beachfill with
structure crest of
+17 ft NAVD88,
dune crest of +18
ft NAVD88 for
35,000 LF from
Beach 9th Street to
Beach 149th
Street, and include
sand tapers at the
ends of the project
• 5 groin extensions,
1 optional groin
rehabilitation
• 13 new groins
• Obtaining sand
from borrow area
located
approximately 2
miles south of the
Rockaway
Peninsula and
about 6 miles east
of the Rockaway
Inlet.
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7. TENTATIVELY SELECTED PLAN (CIRCA 2016)

8. DRAFT BARRIER ALIGNMENT
ALTERNATIVES EVALUATED (CIRCA 2016)
Three alignments of the storm surge barrier originally considered
- Hydrodynamic modeling undertaken for design of openings
- Effects of scour on Gil Hodges Bridge eliminated C-1W
- Impacts to existing utilities considered
C-1E is the preferred alignment, C-2 is close in comparison

9. HIGH FREQUENCY FLOODING RISK REDUCTION
FEATURES (HFFRRFS)
• Due to the scale, complexity, and cost of the
proposed storm barrier, and the need for
additional study, the barrier was moved to
New York/New Jersey Harbor and Tributaries
Feasibility Study which came out of the
North Atlantic Coast Comprehensive Study
(NACCS)
• High Frequency Flooding Risk Reduction
Features (HFFRRFs, formerly ‘Residual Risk
Features’) are designed to complement a
potential future storm surge barrier
• In order to be recommended, each element
must be justified as stand-alone feature
(without the proposed storm surge barrier)
and have a positive benefit-to-cost ratio
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New York and New Jersey Harbor and
Tributaries Study Area—The study team is
evaluating a suite of storm surge barriers in
the region to evaluate potential for regional
storm risk management measures

10. BACK BAY FLOODING
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3yr RP (2068) Flood Extent Verified
5yr RP (2068) Flood Extent Verified
10yr RP (2068) Flood Extent Verified
Flood extents calculated
only within HFFRRF study
area. Excludes Broad
Channel and areas outside
(west) of storm surge barrier
alignment C-1E

11. NATURE BASED FEATURES
LOCATIONS ANALYZED
3 Sites at Arverne
1 Site at
Edgemere
1 Site at Norton
Basin
1 Site at
Bayswater
2 Sites at
Mott’s
Basin
NNBF PROTOTYPE
DEVELOPMENT
 NNBFs created to accommodate a
variation in coastal edge conditions.
 Two main variations are distinguished:
 Horizontal space available between the
urban developed edge and the water line
 Existing plant species composition and the
need to either extend the existing
coastline or cut back the existing bank line
to accommodate a suitable habitat for
wetland creation/enhancement
 Rapidly descending bathymetry near
shoreline
 Limited horizontal width between front toe
of new shoreline slope and flood control
structure on back edge
 Already existing living shoreline habitats
performing CSRM function
 Presence of heavy anthropogenic
infrastructure along shoreline (e.g. docks,
piers).
 Gray feature structures set far back from
shoreline…no interactive capacity.
 Combinations of all these factors (most
likely scenario)
 Does not increase risk of wildlife hazards
to planes; habitat type restrictions near
JFK airport
DID NOT SITE NNBFS WHERE
THERE IS…

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OLD HOWARD
BEACH
CANARSIE
HEAD OF BAY
NORTON BASIN
MOTTS BASIN
INWOOD
BAYSWATER
PARK
Flood extents calculated only within
HFFRRF study area. Excludes
Broad Channel and areas outside
(west) of storm surge barrier
alignment C-1E
ROSEDALE
MEADOWMERE
LAWRENCE
BROAD
CHANNEL
STRUCTURAL
SCREENED,
NONSTRUCTURAL
PASSED
MID-ROCKAWAY
BACK-BAY W/
NNBFs
High Frequency Flooding Risk Reduction
Features - SCREENING RESULTS
• 3 sites are in the Final Plan, including 5 NNBFs at the
Mid-Rockaway Back-Bay site
• Non-structural plan for Broad Channel screened using
data and experience from Build it Back

13. RECOMMENDED PLAN
JAMAICA BAY REACH
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NNBF considered but not
recommended in this location:
• Existing high quality mudflat and
mussel habitat already
performing NNBF functions
• Avoid habitat exchange
Motts Basin North HFFRRF

14. RECOMMENDED PLAN
JAMAICA BAY REACH
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HFFRRF Projects
Mid-Rockaway HFFRRF
Arverne Area/Subreach
(left)
Mid-Rockaway HFFRRF
Edgemere Area/Subreach
• NNBFs are integral features to control erosion
on the berm which will be overtopped
frequently throughout the project life
• NNBF+berm design is more cost effective than
alternative non-erodible floodwall
• BCR underestimates benefits due to “leaving
benefits on the table”

15. 15
New York-New Jersey Harbor and Tributaries
Coastal Storm Risk Management Feasibility Study
ALTERNATIVES OVERVIEW
• Alternative 1: No Action
• Alternative 2: Harbor Wide Gate and Beach Restoration
• Alternative 3A/3B: Multiple Bay/Basin Gate and Floodwalls & Levee Systems
• Alternative 4: Individual Waterbody Gate and Floodwalls & Levees
• Alternative 5: Perimeter Only
New York Harbor.

16. ALTERNATIVE 1: NO ACTION (FUTURE WITHOUT PROJECT CONDITIONS)
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17. ALTERNATIVES 2-5
• Alternative No. is a reference to the scale of solution and general strategy
• Siting and quantities are approximate for screening purposes and will be refined
• Design level 1% event (mean) + RSLC + Wave Run-up (measure and location specific)
• Focus on biggest cost drivers (storm surge barrier) in each alternative
• Nonstructural, NNBF, and perimeter structural placeholders to be refined in future
formulation
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New York-New Jersey Harbor and Tributaries
Coastal Storm Risk Management Feasibility Study
Alt. 2 Alt. 3A Alt. 3B Alt. 4 Alt. 5
In-Water
Measures
Land-Based
Measures

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New York-New Jersey Harbor and Tributaries
Coastal Storm Risk Management Feasibility Study
Alternatives at AMM
Best performing alternatives
(Draft Interim Report)
TSP and Draft Report
Work needed to identify TSP
Parametric analyses
ADM and optimization
Recommended Plan

24. FACTORS CONSIDERED - ALTERNATIVE SCREENING
1. Hydrodynamic Modeling
Induced Flooding during Storms
Tidal Influences
2. Relative Sea Level Change
Based on intermediate
3. Period of Analysis
50 year period may limit full evaluation given many measures will
likely have far longer period of utility
4. Operations and Maintenance Assumptions
Storm event condition selected for surge gate operation has
substantial effects on plan selection
5. Benefits Model
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New York-New Jersey Harbor and Tributaries
Coastal Storm Risk Management Feasibility
Study

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New York-New Jersey Harbor and Tributaries
Coastal Storm Risk Management Feasibility Study
ENVIRONMENTAL CONSIDERATIONS
 Changes to tidal range/regime, flow velocity, salinity concentrations, sedimentation rates,
scour, and elevation
 Water quality, dissolved oxygen, nutrients, and phytoplankton biomass (i.e.
eutrophication), and pathogenic bacteria
 Anadromous/catadromous fish migration and aquatic species
 Marsh inundation
 Air quality
 Transportation (marine vessels, etc.)
 Aesthetics and recreation
 National Historic Landmarks and
Historic Properties
 Listed species and critical habitat
 Noise and vibration
 Bay bottom impacts, as well as landside impacts
 Location of Superfund, National Priority List, and other contaminated sites
Jamaica Bay, New York City

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New York-New Jersey Harbor and Tributaries
Coastal Storm Risk Management Feasibility Study
PUBLIC INVOLVEMENT
 Scoping Period through November 5th
 Release of the Draft Interim Report – Winter 2019
 Public/ Agency Reviews with Public Meetings
 Draft Feasibility Report and Tier 1 EIS – Spring 2020
 Public/ Agency Reviews with Public Meetings
 Optimization of the Selected Plan
 Final Feasibility Report and Tier 1 EIS – Spring 2021
 Chief’s Report – Summer 2022
 Public Involvement during Pre-Construction Engineering
and Design Phase –Tier 2 EIS
*The red boxes indicate the best opportunities for the public to
provide input to the study.
The scoping period extends until
November 5, 2018. Comments
and input submitted by this
deadline will be used to develop
the Draft Interim Report.
Comments received after the
deadline are welcome and will be
used to help identify the Tentatively
Selected Plan (TSP) in 2020.
Once the Draft Interim Report is
released, the public and agencies
will have a chance to review and
submit comments and public
meetings will be held as part of the
public review period. The
comments are used to inform the
agency as it moves to identifying
the TSP.

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New York-New Jersey Harbor and Tributaries
Coastal Storm Risk Management Feasibility Study
STUDY SCHEDULE
Milestones
Milestones Dates*
Draft Interim Report Winter 2018/2019
Draft Feasibility Report and Tier 1 EIS Spring 2020
Final Feasibility Report and Tier 1 EIS Spring 2021
Chief’s Report (for Congress) Summer 2022
* The schedule is contingent upon available funding, non-federal partner
support, and concurrence by Corps higher-authority offices.

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New York-New Jersey Harbor and Tributaries
Coastal Storm Risk Management Feasibility Study
HOW TO STAY INVOLVED
Project Webpage
http://www.nan.usace.army.mil/Missions/Civ
il-Works/Projects-in-New-York/New-York-
New-Jersey-Harbor-Tributaries-Focus-Area-
Feasibility-Study/
Stakeholder Mailing List
Email
NYNJHarbor.TribStudy@usace.army.mil
if you would like to join our mailing list
and receive periodic updates.
Scoping Comments
Send any questions and/or comments
to
NYNJHarbor.TribStudy@usace.army.
mil
OR
Fill out and submit a comment card at
a scoping meeting
Scoping Comment Period open
through November 5, 2018

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JAMAICA BAY PLANNING REGION EFFORTS
Elders Point East and
West Marsh Islands
Restoration (Mitigation
for NY Harbor and CAP
Beneficial Use of
Dredged Material):
Constructed 2007 & 2010
Black Wall and
Rulers Bar Marsh
Islands Restoration
(NY Harbor Sand
Placement):
Constructed 2012
and differential cost
paid for by sponsor.
Existing
Rockaway
Project:
Constructed 1977
and Repaired in
2014.
Proposed Ecosystem Restoration Sites
Jamaica Bay
Navigation Channel:
O&M Dredging in 2019
(subject to availability
of funds)
Plumb Beach
CSRM Project
(CAP Beneficial
Use of Dredged
Material):
Constructed
2012/2013
Gerritsen Creek
Restoration (CAP
Section 1135):
Constructed 2011
Hudson Raritan
Estuary (HRE)
Proposed Restoration
Sites
Yellow Bar Hassock
Marsh Island
Restoration (CAP
Beneficial Use of
Dredged Material):
Constructed 2012
East Rockaway
Inlet Navigation
Channel: O&M
Dredging in 2019
(subject to
availability of Funds)
Spring Creek South
CSRM/Restoration
(NYSDEC/FEMA IIS):
60% designs completed
and EA public release
August 2018
Spring Creek North
Restoration (CAP Section
1135): Report approved
Mar 2018 and D&I PPA
scheduled Jul 2018

30. SPRING CREEK SOUTH
FEMA HAZARD MITIGATION GRANT
PROGRAM (HMGP) PROJECT
Goals
• Manage coastal storm risk with Natural/nature-based features;
Decrease risk of fire
• Align with NPS Gateway National Recreation Area (GNRA)
Management Plan
• Coordinate with complementary Jamaica Bay projects
• Recommended Plan
 Berm - 19 feet NAVD 88; 50-foot-wide path at crest
 Tie-ins at Belt Parkway and Addabbo Bridge
 Freshwater wetlands
 Flap gates
 Local access points; Improved edge aesthetic