US Army Corps of Engineers

BUILDING STRONG®

Atlantic Coast of New York

East Rockaway Inlet to Rockaway

Inlet and Jamaica Bay, NY

Reformulation

Jamaica Bay Overview

BUILDING STRONG®

Authorized Study Area

2

BUILDING STRONG®

Scale of the Problem Blue illustrates current 1% annual chance of flooding

Purple illustrates 1.3 feet of RSLC in 2070, (mid-range SLC) added to the 1% Annual chance of flooding

3

BUILDING STRONG® 4

BUILDING STRONG®

1965 Authorized Project Features

BUILDING STRONG®

June 21, 1965

“…the Chief of Engineers has recommended

that field studies and hydraulic model

investigations are to be conducted in

connection with the final design of the

project to determine the specific effects of

the proposed hurricane barrier on water

quality, fish, and wildlife, and currents in

Jamaica Bay…”

6

BUILDING STRONG®

Reformulation Study

Recommendation of the Federal Project

is based on benefit/cost ratio

Primary purpose for P.L. 113-2 is the

reduction in future coastal flooding

damages

7

BUILDING STRONG®

Reduce vulnerability to storm surge impacts

Reduce future flood risk in ways that will support the long-

term sustainability of the coastal ecosystem and communities

Reduce the economic costs and risks associated with large-

scale flood and storm events

Improve community resiliency, including infrastructure and

service recovery from storm effects

Enhance natural storm surge buffers and improve ecosystem

resiliency

Other Opportunities

8

BUILDING STRONG®

Constraints

Do not negatively impact ongoing recovery, ecosystem restoration, and risk

management efforts by others

Do not negatively impact navigation access through Rockaway Inlet

Do not induce flooding in areas not currently vulnerable to flooding and do

not induce additional flooding in flood-prone areas

Do not reduce community access and egress during emergencies

Do not impact operations at John F. Kennedy International Airport

Do not negatively affect plants, animals, or critical habitat of species that are

listed under the Federal on NYS Endangered Species Act

BUILDING STRONG® 10

BUILDING STRONG®

Jamaica Bay Measures

Nonstructural

Acquisition

Managed Retreat

Floodplain zoning

Floodproofing/raising

Flood warning system

Structural

Hurricane barrier

Local Tide Gates

Levee

Floodwall

Bulkhead/Seawall

Breakwater

Natural or Nature Based

Living shoreline

Coastal wetland

Maritime and coastal forest

Reef

Dune and Beach

Swale/Channel

Other

Bay shallowing

Stormwater improvement

Wastewater treatment

Park access and recreation

Evacuation routes

11

BUILDING STRONG®

Measure Screening

12

Blue=Effective Green=Effective only for high frequency events

BUILDING STRONG®

13

BUILDING STRONG® 14

BUILDING STRONG® 15

BUILDING STRONG®

BUILDING STRONG®

BUILDING STRONG® 18

Table 27: Percentage of Existing Tidal Amplitude

Opening Width Plan C-1 Plan C-2 Plan C-3

1,000 feet 58% 73% 58%

2,000 feet 91% 90% 70%

3,000 feet N/A 93% 79%

4,000 feet N/A 95% 81%

5,000 feet N/A N/A 90%

Note: N/A indicates that the opening width is not feasible for this alignment

BUILDING STRONG®

Structural Alternative Plan

Evaluation Jamaica Bay Alternatives Preliminary Average Annual Net Benefits

(AAEQ) Plan Name Total Annual

Cost

Benefits Net Benefits BCR

Barrier C-1b $148,012,000 $265,833,000 $117,821,000 1.80

Barrier C-2b $118,669,000 $265,833,000 $147,164,000 2.24

Barrier C-2c $141,900,000 $265,833,000 $123,933,000 1.87

Barrier C-2d $165,131,000 $265,833,000 $100,702,000 1.61

Barrier C-3e $214,430,000 $265,833,000 $51,403,000 1.24

Head of Bay $36,550,000 $71,036,000 $34,486,000 1.94

Rock Back Bay $18,809,000 $67,896,000 $49,087,000 3.61

BC Breakwater $45,124,000 $13,390,000 ($31,734,000) 0.30

Jam Bay NW $101,986,000 $113,511,000 $11,545,000 1.11

Note: EADs and AAEQ costs calculated at FY14 price levels, 3.5% discount rate, and 50-year period of analysis

BUILDING STRONG®

Jamaica Bay Alternatives

No Action Alternative

Non-Structural Alternative (can be mixed with other Alts)

Rockaway Inlet Hurricane Barrier

► Provides Benefits to all Economic Reaches

Jamaica Bay Perimeter Walls w/ Living Shorelines where

appropriate (Perimeter Plan)

► Individual Plan Developed for each Economic Reach

► Negative BCR for Broad Channel, and not applicable

for JFK area

20

BUILDING STRONG® 21

BUILDING STRONG®

Preliminary Focused Array

Comparison

(without Real Estate or Mitigation costs)

Plan Name Total Costs Annualized

Costs

Annualized

Benefits

BCR

“Best” Inlet

Barrier

$2,743,300,000 $118,669,000 $265,833,000 2.24

Head of

Bay

$834,250,000 $36,550,000 $71,036,000 1.94

Rockaway

Back Bay

$313,168,000 $18,809,000 $67,896,000 3.61

NW Jam

Bay

$2,300,156,500 $101,966,087 $113,511,000 1.11

Perimeter

Total

$3,447,574,500 $157,325,087 $252,443,000 1.60

22

BUILDING STRONG®

Choosing A Path Forward

Further develop Jamaica Bay alternatives, including operational

considerations (O&M can be expensive)

Estimate real estate and hazardous waste costs

Integrate ocean and bay alternatives

Define tie in features

Refine hydrodynamic modeling of Jamaica Bay

Improve quantification of environmental effects (WQ & habitats)

Collaboration with regulatory agencies to inform environmental

thresholds, prioritize analysis

Detail and broaden analysis of plan benefits

Emphasize natural and nature based features and resiliency

23