hurricane protection in southern louisiana briefing outline 1. authority lacpr 2. december 2005...

Hurricane Protection In Southern LouisianaHurricane Protection In Southern Louisiana

Briefing Outline1. Authority LACPR2. December 2005 Workshop3. Surge and Wave Modeling

System4. JPM-OS5. List of External Scientist and

Academics6. List of Participating Organizations7. Questions?

Public Law 109-103Energy and Water Development Appropriations Act, 2006

DEPARTMENT OF THE ARMY

Corps of Engineers--Civil

The following appropriations shall be expended under the direction of the Secretary of the Army and the supervision of the Chief of Engineers for authorized civil functions of the Department of the Army pertaining to rivers and harbors, flood control, shore protection and storm damage reduction, aquatic ecosystem restoration, and related purposes.

INVESTIGATIONS

….That using $8,000,000 of the funds provided herein, the Secretary of the Army, acting through the Chief of Engineers, is directed to conduct a comprehensive hurricane protection study at full Federal expense to develop and present a full range of flood, coastal and hurricane protection measures exclusive of normal policy considerations for south Louisiana and the Secretary shall submit a feasibility report for short-term protection within 6 months of enactment of this Act, interim protection within 12 months of enactment of this Act and long-term comprehensive protection within 24 months of enactment of this Act: Provided further, That the Secretary shall consider providing protection for a storm surge equivalent to a Category 5 hurricane within the project area and may submit reports on component areas of the larger protection program for authorization as soon as practicable: Provided further, That the analysis shall be conducted in close coordination with the State of Louisiana and its appropriate agencies.

…..long-term comprehensive protection within 24 months of enactment of this Act: Provided further, That the Secretary shall consider providing protection for a storm surge equivalent to a Category 5 hurricane within the project area and may submit reports on component areas of the larger protection program for authorization as soon as practicable…….

Category 1 74 – 95 mph windsCategory 2 96 – 110 mph windsCategory 3 111 – 130 mph windsCategory 4 131 – 155 mph windsCategory 5 155+ mph winds

Saffir-Simpson Scale

Hurricane WorkshopERDC Vicksburg, MS

Agenda for 20-21 Dec 2005Day 10800 Welcome - ERDC0810 Introductions – All0820 Agenda and Meeting Objectives – MVN Stutts0830 New Orleans Flood Protection System and it’s design – MVNAnderson and Hote0900 Impact of Katrina - MVN N. Powell0930 Break0945 Enhanced Protection Plan – MVN Anderson and Axtman1015 Dutch Sea Defense and the Role of Models – DELFT Stelling1100 Climatology of Hurricane Landfalls and Analysis & ForecastingHurricane Structure - NOAA Beven1145 Lunch1235 Experienced Hurricane Windfields - NOAA M. Powell 1305 Wave Prediction in SE Louisiana - ERDC Smith 1335 Storm Surge Prediction in SE Louisiana – UND Westerink 1405 Storm Surge Prediction (SLOSH) – NWS Shaffer1435 Break 1450 Nearshore Waves and Wave Effects on Storm Impact – UNESCO-IHE Roelvink 1520 Estimating Storm Frequency - ERDC Resio and Vickery1550 Comments on proposed plan concepts and ideas for providingprotection plans to be examined Part 11700 End day 1

Day 2 0800 Review Workshop Objectives - MVN Stutts Rest of Workshop Facilitated by Ebersole 0815 Level of Protection and Proposed Plan 0845 Recommendations for design approach 0915 Hurricane Intensity and Frequency Estimating0945 Wind and Pressure Prediction 1015 Break

Hurricane Workshop

ERDC Vicksburg, MS

Agenda for 20-21 Dec 2005

Conclusions from WorkshopConclusions from Workshop

Needs IdentifiedNeeds Identified

Risk Assessment Group –RAGSurge and Wave Modeling GroupInnovative Design GroupITR Group

Modeling System

Wind Field – Wind Stresses

Surge Model Wave Models

TC96 PBL

Offcoast Waves: WAMNearshore Waves:STWAVE

Unified GridSurge model:ADCIRC

Coupling

Local Scale Waves:Boussinesq - Parametric

•IPET

•FEMA

•LaCPR

•MsCIP

ADCIRC Grid Domain

WAM Model Domain

LaCPR and MsCIP

STWAVE Model Domains

Peak Surge and Waves

Hurricane Surge ParameterizationConclusions

• Storm size is important, especially for:• Mildly-sloping regions• Very intense storms

• Demonstrated:Surge(large, moderately intense) > Surge(small, very intense)

Category 3Rmax = 47 km (25 nmi)cp = 919 mbpeak surge = 7.5 – 8.5 m (24.5 – 27.8 ft)

Category 5Rmax = 22 km (12 nmi)cp = 910 mbpeak surge = 6.4 – 6.9 m (21 – 22.6 ft)

Irish

IRISH et al. (JPO – with revisions) showed that major response was Dp –Rp plane,not just storm intensity.

max max( ) ... ( , , , , ) [ ( , , , , ) ] ( , , , , )

is a random deviation due to all the neglected factors

This includes both surge-independent terms (tide and model error)

p f l p f l p f lF p P R v x H P R v x P R v x

where

and surge-dependent

terms (Holland B), etc.

New JPM:The estimation of the surge CDF includes a “random” deviation term added to the modeled values. In this way we can retain important aspects of variations that would add too many dimensions to the integral to make it practical.

After some analyses of different types both Toro and Resio ended up using about 150 storms in this sum and similar magnitude epsilon terms.

Later described in The White Paper as the JPM-OS, Joint Probability – Optimal Sampling Technique

Parameter Space– Cp = 900 to 960 mb– Rmax = 6 to 35.6 nm– Vf = 6 to 17 knots

Storms

LaCPR & MsCIP

MsCIP

QUESTIONS?QUESTIONS?