Prediction of coastal flooding at residence zones and transportation infrastructure at the east bank of Delaware Bay in sea‐level rise conditions

Hansong Tang1, Steven I-Jy Chien2, Marouane Temimi1 Cheryl Ann Blain3, Qu Ke1, Liuhui Zhao2, Simon Kraatz1

1 NOAA CREST/Dept. Civil Eng., CCNY 2 Dept. of Civil and Environ. Eng., NJIT 3 Oceanography Div., Naval Research Lab

8th Annual NOAA‐CREST Symposium, CCNY, June 6, 2013 Sponsored by UTRC/CREST

Outline

1. Motivation, challenge, and approaches

2. Region of study and data collection

3. Modeling flooded population and transportation system: Methodology

4. Results and analysis

5. Concluding remarks

1. Motivation, challenge, and approaches

Higher potential for coastal flooding, especially at NY/NJ coastlines

Sea level rise (in 100 yrs, 0.2 – 0.6 m, even 0.8 – 2 m), strong hurricanes become more frequent residence area, transportation system, etc. at risk Objective Propose a modeling approach for coastal flooding, especially local flooding Case study at Cape May and Cumberland, NJ (one of the country's oldest vacation resorts, at most a few meters above sea level, frequently flooded)

Motivation and Objective

1. Motivation, challenge, and approach

Challenges flooding modeling with accuracy and detail (traffic way, bridge, etc.) –- require advanced approach and intensive computing besides coastal water, land runoff also contribute to flooding -- coupling is need population data collection -- population distribution, changes with time

Approaches high resolution approach coupling of hydrodynamics and hydrology population/flooding overlay, a model for future population

Challenge and Approach

Region of Study

West side of Delaware BayAve depth 7 – 30 m

2. Region of study and data collection

Roads, Railroads, and Bridges

Population 2010 in Cape May and Cumberland Counties (US Census Bureau 2013)

2. Region of study and data collection

Sea Level Rise, Storm, Bathymetry, and Cases of Study

Sea level rise: IPCC

Observation for storm: nor’easter

Bathymetry and topography: NGDC, LIDAR, and USGS DEM

Cases of study:

ScenariosFrequency, projected sea-level rise

(NAVD88)

current, 0 m 10 yr, 0.09 m 50 yr, 0.42 m

Storm

returning

period, peak

elevation value

no-storm, 0 m 0 1 2

10-yr, 1.63m 3 4 5

50-yr, 1.79m 6 7 8

3. Modeling flooded population and transportation system: Methodology

Hydrodynamics Model

Shallow water model

FVCOM

External mode

Internal mode

Mesh and model setup (FVCOM 3000 elements, SWM 40,000 elements)

3. Modeling flooded population and transportation system: Methodology

Hydrodynamics Model Calibration

Hydrodynamic model calibration. Line – modeling, circle – measurement. a) and b) Current velocity measured at Brown Shoal Light. c) Surface elevation at Ship John Shoal

3. Modeling flooded population and transportation system: Methodology

Hydrology Model and Flooding Determination

]-

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1

maxdd

falt

p

minpp ff

Hydrologic model of runoff flooding (fp --flood potential, -- elevation, d – distance to water)

Flooding determination

F=0, dry. F>, = 1 flooded

.,0,3

,,0,2

,,0,1

,,0,0

min

min

min

min

pp

pp

pp

pp

ffD

ffD

ffD

ffD

F

alt

4. Results and analysis

Prediction of Population

Projected population in municipals using a model that considers future trends on mortality, fertility, migration, etc.

Municipalities 2010 2020 2060

Avalon borough 1,334 1,352 1,408

Cape May city 3,607 3,657 3,807

Cape May Point borough 291 295 307

Dennis township 6,467 6,556 6,826

Lower township 22,866 23,180 24,135

Middle township 18,911 19,171 19,960

North Wildwood city 4,041 4,096 4,265

Ocean City city 11,701 11,862 12,350

Sea Isle City city 2,114 2,143 2,231

Stone Harbor borough 866 878 914

Upper township 12,373 12,543 13,059

West Cape May borough 1,024 1,038 1,081

West Wildwood borough 603 611 636

Wildwood city 5,325 5,398 5,620

Wildwood Crest borough 3,270 3,315 3,451

Woodbine borough 2,472 2,506 2,609

Cape May County Total 97,265 98,600 102,661

Bridgeton city 25,349 26,690 32,248

Commercial township 5,178 5,452 6,587

Deerfield township 3,119 3,284 3,968

Downe township 1,585 1,669 2,016

Fairfield township 6,295 6,628 8,008

Greenwich township 804 847 1,023

Hopewell township 4,571 4,813 5,815

Lawrence township 3,290 3,464 4,185

Maurice River township 7,976 8,398 10,147

Millville city 28,400 29,903 36,130

Shiloh borough 516 543 656

Stow Creek township 1,431 1,507 1,820

Upper Deerfield township 7,660 8,065 9,745

Vineland city 60,724 63,937 77,251

Cumberland County Total 156,898 165,200 199,600

4. Results and analysis

Prediction of Flooding

a) Hydrodynamic b) Hydrology c) Hydrodynamics/Hydrology

Sea Level Rise (years)

FloodingArea(km2)

0 20 40 60

0

20

40

60

80

100non_storm10 year_storm50 year_storm

Time (hours)

FloodingArea(km2)

0 20 40 60 80 100 120

0

20

40

60

80

100

50year_storm_non SLR50year_storm_10 year SLR50 year_storm_50 yearSLR

a) Zoom in flooding b) Flood area vs time c) Flood area vs sea level

4. Results and analysis

Various Flooded Zones

Prediction of various flooded zones

4. Results and analysis

Distribution of Flooded Population

Prediction of various flooded zones

4. Results and analysis

Numbers of Affected Population

 MunicipalsScenarios

1 2 3 4 5 6 7 8

Cape May Point Borough 254 187 253 255 284 257 259 293

Dennis Township 0 0 116 171 718 193 241 756

Lower Township 596 106 1,246 1,702 5,704 1,637 1,994 6,928

Middle Township 193 122 1,092 1,208 3,118 1,254 1,378 3,571

West Cape May Borough 0 0 0 0 0 0 0 10

Cape May County Total 1,043 415 2,707 3,336 9,824 3,341 3,872 11,558

Commercial Township 109 281 326 354 481 346 386 522

Downe Township 352 418 367 404 533 403 438 586

Fairfield Township 6 9 15 19 37 23 25 81

Greenwich Township 6 7 21 23 343 147 241 363

Hopewell Township 0 0 0 0 0 0 0 11

Lawrence Township 37 55 59 66 86 66 73 89

Maurice River Township 24 67 337 377 557 371 412 624

Stow Creek Township 0 0 29 34 48 34 40 51

Cumberland County Total 534 837 1,154 1,277 2,085 1,390 1,615 2,327

4. Results and analysis

Distribution of Flooded Transportation Facilities

4. Results and analysis

Flooded Transportation System

Affected bridges

Affected length (centerline miles) of roadways

Affected length (miles) of railroads

“–” represents a bridge is not located in a flooded area under that scenario “x” represents a bridge is possibly flooded because it is located in a flooded area “f” represents a bridge located in a flooded area will be flooded “n” represents a bridge located in a flooded area will not be flooded

A multi-disciplinary approach is proposed to predict coastal flooding and its impact on residents and transportation systems, and it is applied to study future coastal flooding at the east bank of Delaware Bay.

Sea-level rise will lead to a substantial increase in vulnerability of residents and transportation

infrastructure to storm floods.

A flood tends to affect more population in Cape May County, more transportation facilities in Cumberland County, New Jersey.

Summary

5. Concluding Remarks