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US Army Corps of Engineers
BUILDING STRONG®
South San Francisco Bay Shoreline Studies
for EIA 11 with Project Conditions U.S. Army Corps of Engineers
San Francisco District
Ms. Lisa Andes
Mr. Craig Conner
Dr. Frank Wu
Dr. Jen-Men Lo
Dr. Michael MacWilliams
Dr. Chia-Chi Lu
Dr. Robert Dean
Project Site
2
Focus Area
Project History
2004 - 2005 Funds received/FSCA signed/Project Start
October 2005 – May 2010 Modeling of without project
conditions to support Feasibility Scoping Meeting (FSM)
September - December 2010 – FSM held, HQ comments
resolved, and approved to continue project
November 2010 - February 2011 – Project re-scoped
(reduced size)
October 2011 – Switched hydrodynamics model
June 2012 – Most technical work completed and Decision
Making Conference held
March 2013 – 1st Draft of Feasibility Report & EIS/EIR
April 2013 – Preparing for the Alternative Formulation
Briefing with HQ USACE
Project Sponsors
Technical Team Dr. Frank Wu – Co – Technical Manager
► USACE, San Francisco District
Dr. Jen-Men Lo – Co – Technical Manager
► Santa Clara Valley Water District
Dr. Michael MacWilliams – Hydrodynamic Modeling
► Delta Modeling Associates, Inc.
Dr. Chai-Chi Lu – Statistical Analysis/Monte Carlo Simulation
► Noble Consultants, Inc.
Mr. Brian Hubel / Dr. Nick Malasavage – Levee Failure
► USACE, San Francisco District
Dr. Robert Dean – Technical Review
► University of Florida
Mr. Craig Conner – Flood Risk Manager
► USACE, San Francisco District
Project Purpose
1. Flood Risk Management –
Estimate a combined fluvial
and coastal design water
surface elevation for levee
construction
2. Ecosystem Restoration –
include in wetland restoration
alternatives in design water
surface elevation
100
101
102
103
9
9.5
10
10.5
11
11.5
Wa
ter
Su
rfa
ce
Ele
va
tio
n (
fee
t, N
AV
D8
8)
Return Period (years)
YR0 NED - Water Surface Elevation at Point 3
Expected Value
90% Confidence Limit (5% & 95% Confidence Level)
Flood Stage Frequency Curve
South San Francisco Bay
(Risk and Uncertainty Based Approach)
Project Challenges
1. Lack of site specific
water surface
elevation data at the
project site
2. Over 150 years of
measured water
surface elevation at
the San Francisco
Tide Station
NOAA Tide Stations in the Central and
South Bay
Coastal Engineering Components
• Physics (tide, surge wind, wave run-up & over topping, levee stability & fluvial flow)
• Numerical Modeling (Yr-0 and Yr-50, With-Project Conditions)
• Statistical Analysis: 1. Extreme Probability Method
(EPM)
2. Joint Probability Method (JPM)
3. Monte Carlo Simulation (MCS)
• Sea Level Rise (NRC Curve III)
12/02 12/02 12/03 12/04 12/05-2
0
2
4
6
8
10
Date (mm/dd/1983)
WS
E, N
AV
D 8
8 (
fee
t)
Measured Tide
Predicted Tide
Residual Tide
Tide and Surge Analysis at the San
Francisco Tide Station
Residual Tide and Astronomical Tide are in Phase
Residual Tide ~= 2.4’
Astronomical Tidal
Amplification
Astronomical
Tide is
amplified from
San Francisco
to South Bay 05/16 05/17 05/18 05/19 05/21-4
-2
0
2
4
6
8
10
Date mm/dd/2011
WS
E, N
AV
D8
8 (
fee
t)
WSE Measured at Coyote (9414575)
WSE Measured at San Francisco (9414290)
Residual Tide in the
South Bay
Approximately no change in
residual tide as it propagates to the
south bay
Resid
ual T
ide (
m)
South Bay Model Grid Model Domain
Note: Bathymetry used in grid development
was CEPD* compliant
*CEPD – Comprehensive Evaluation of Project Datums, EM 1110-2-6056
Look-Up
Table
Tide at San Francisco Evaluation Location
Event Astronomical
(feet, MLLW)
Residual
(feet) 7 16
1 5.15 0.5 6.09 5.74
2 5.15 2.5 7.84 7.76
3 5.85 0.5 6.54 6.36
4 5.85 2.5 8.57 8.50
5 6.55 0.5 7.04 6.88
6 6.55 2.5 9.08 9.02
7 7.25 0.5 7.72 7.61
8 7.25 2.5 9.98 9.90
Outer Levee
Proposed Inner Levee 1
Proposed Inner Levee 2
Model Simulations Include:
with and without wind and
with and without levee
failure scenarios
Conditional Sampling Criteria
Scenario Measured Tide
>= MLLW (ft)
Residual Tide
>= (ft)
Number of
Events
Sampled
Rate of
Occurrence
(Event #/yr)
1 6.9 0.0 522 4.97
2 6.9 0.5 276 2.63
3 6.9 1.0 93 0.89
4 Annual Maximum -- 105 1.0
12/01 12/06 12/11 12/16 12/21 12/26 12/31-2
0
2
4
6
8
10
Date (mm/dd/2002)
Tid
e (
ft)
Measured Tide
Predicted Tide
Residual Tide
6.9 Feet Above MLLW
What WSE is
justified to be
considered as a
storm event in
extreme coastal
and fluvial flood
statistics?
Extreme Probability Method
100
101
102
103
6
6.5
7
7.5
8
8.5
9
9.5
10
Return Period (yrs)
Flo
od
Sta
ge
(ft, M
LL
W)
Gumbel Fit: Measured Tide >= 6.9 & Residual Tide >= 0.0
Gumbel Fit: Measured Tide >= 6.9 & Residual Tide >= 0.5
Gumbel Fit: Measured Tide >= 6.9 & Residual Tide >= 1.0
Gumbel Fit: Annual Maximum Measured Tide (Reference Senario)
0 10 20 30 40 50 60 700
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
Wind Speed (MPH)
Pro
ba
bility
Wind : 292.5o
Wind : 315.0o
0 50 100 150 200 250 300 3500
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.18
Wind Direction (0, True North)
Pro
ba
bility
0 0.5 1 1.5 2 2.5 30
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.18
0.2
Pro
ba
bility
Residual Tide (feet)
4.5 5 5.5 6 6.5 7 7.5 8 8.50
0.02
0.04
0.06
0.08
0.1
0.12
Pro
ba
bility
Astronomical Tide, MLLW (feet)
Probability Distribution Functions
(PDFs)
Residual Tide
Predicted Tide
Wind Speed
Wind Direction
Monte Carlo Simulation Process
Astronomical Tide Residual Tide / Surge
Wind Speed / Direction Riverine Inflows
Long Wave Model Short Wave Model
Hydrodynamic Forcing on Levee
Outboard Levee Failure
Inboard Levee Failure
Basin Flooding Analysis / End Result
LWM No Breach LWM w/ Breach
Forcing Functions
Fluvial Flow Rate
Hydraulic Modeling (HEC-RAS)
Breakout Flow
No YES No Fail Fail
No Fail Fail
Risk & Uncertainty
Analysis
18
100
101
102
103
9
9.5
10
10.5
11
11.5
12
Wa
ter
Su
rfa
ce
Ele
va
tio
n (
fee
t, N
AV
D8
8)
Return Period (years)
Water Surface Elevation at Point 7
Joint Probability Distribution
Gumbel Maximum Distribution
Expected Value
5% & 95% Confidence Levels
Risk & Uncertainty
Analysis
Effect of Outer
Levee Breach:
1. Breach
Condition
2. No Breach
Condition
100
101
102
103
4
5
6
7
8
9
10
Wa
ter
Su
rfa
ce
Ele
va
tio
n (
fee
t, N
AV
D8
8)
Return Period (years)
Water Surface Elevation at Point 16
Expected Value
90% Confidence Limit (5% & 95% Confidence Level)
Sea Level Rise Comparison of Water Surface Elevation between
Year 0 and Year 50 NRC Curve III
100
101
102
103
11
11.5
12
12.5
13
13.5
Wa
ter
Su
rfa
ce
Ele
va
tio
n (
fee
t, N
AV
D8
8)
Return Period (years)
Water Surface Elevation at Point 16
Expected Value
90% Confidence Limit (5% & 95% Confidence Level)
100
101
102
103
4
5
6
7
8
9
10
Wa
ter
Su
rfa
ce
Ele
va
tio
n (
fee
t, N
AV
D8
8)
Return Period (years)
Water Surface Elevation at Point 16
Expected Value
90% Confidence Limit (5% & 95% Confidence Level)
Year 0 (2017) Year 50 (2067)
WSE between 4.5 and 9.5, feet NAVD88 WSE between 11.3 and 13.0, feet
NAVD88
Includes: Sea Level Rise (2.13 feet) and
estimated bathymetric change
Summary and Conclusions
1. Correct coastal physics associated with
tide (predicted and residual) were used
2. The wind set up contribution is negligible
3. MCS provides reasonable estimates of
coastal flood stage frequency curve with
uncertainty limits
4. MCS, EPM and JPM seem to compare
well and demonstrate consistency
Next Steps
Technical work (including modeling) is currently
in the Corps review process
~ July 2013 - will hold the Alternative
Formulation Briefing (AFB) with HQ USACE
~ August – September 2013 - AFB material will
be available to the public
~ September 2013 – will hold a public meeting on
the Administrative Draft Feasibility
Report/EIR/EIS
~ June 2014 Report of the Chief of Engineers
released
~ 2017 – Start of Project Construction*
* Pending authorization & appropriations