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CBen C. Gerwick, Inc.
a COWI company
Ben C. Gerwick, Inc. // COWI North America
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Z Ben C. Gerwick, Inc.
a CON Company
Over 90 years of expertise in heavy civil construction and design
Ben C. Gerwick, Inc.
> Internationally renowned engineering
consulting firm HQ in Oakland, CA
> History of creative solutions that
minimize risk, cost, and time
> Focused on constructability,
serviceability, maintenance, and
durability of structures in waterways
and marine sites
> Conceptual design, cost estimates
planning, permitting, final design and
construction support
> Documentation & quality control
> Decades of experience with
government design criteria to
streamline the approval and permitting
process
> Work is exemplified by New Orleans
IHNC Floodgates, Braddock Dam,
Olmsted Dam, and Chickamauga Lock.
3 Ben C. Gerwick, Inc.
a COWI company
Select projects
> IHNC Lake Borgne Barrier (Design/
Constr. Supt.)
> Montezuma Slough Salinity Barrier
(Concept. Des./ Constr. Eng.)
> Braddock Dam (Design/ Constr.
Supt.)
> Chickamauga Lock (Design/ Constr.
Eng.)
> Olmsted Lock and Dam (Design/
Constr. Eng.)
> Venice Storm Surge Barrier
(Conceptual Des.)
4 Ben C. Gerwick, Inc.
a COWI company
IHNC Hurricane Protection Project
New Orleans, Louisiana
> Gerwick is the Lead Designer for the
$1.3- billion design -build contract for
the USACE Hurricane Protection
Office. The barrier reduces the risk
of damage from 100 -year and 500 -
year storms.
> Gerwick designs: 150' Swing Gate,
GIWW Sector Gate Monolith,
Approach Walls, and the flood wall
itself.
> Gerwick provided construction
support, on -site staff for project
duration, cost estimating assistance,
management of mech. subs, QC,
and documentation.
Sector Gate (150') & Swing
5 17 JANUARY 2013 Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT COMMITTEE
a COWI company
Gerwick's concept allowed for in- the -wet methods to expedite construction
IHNC Hurricane Storm Damage Risk Reduction
System
6 17 JANUARY 2013 Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT COMMITTEE
a CON company
Flood Wall Construction - August 2009
36" Diameter Steel Piles
Driven to EL -190 ft
ly
^N°^ 2013 Ben C. Gerwick, Inc.
7 rnoe; ANDS MANACEPIENT COMNli r E
a CON company
IHNC Gate Structures at Gulf Intracoastal Waterway
(GIWW)
1I JANUARY ANA Ben C. 6erwick, Inc.
8 TIDELANDS MANAGEMENT CDMMITT[E
a COWI company
Construction sequence - January 2011
IHNC Swing Gate Tow to Site - January 2011
9 17 JANUARY 2013 Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT COMMITTEE
a CON Company
A cost efficiency review
IHNC Floodwall vs. Existing and Proposed Barriers
Gerwick's base case
barrier as a unit cost of
Lake Borgne
$0.75 billion / mile
St Petersburg
Proposed NY -NJ
CH2MHill barrier
NY -NJ
(concept only)
Oosterscheld
Maeslant
River Thames tidal
I
barrier in London, UK
Thames
17 JANUARY 2013
1 TIDELANDS MANAGEMENT COMMITTEE
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11
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0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5
($ billion 1 mile)
Ben C. 6erwick, Inc.
a COW company
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0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5
($ billion 1 mile)
Ben C. 6erwick, Inc.
a COW company
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0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5
($ billion 1 mile)
Ben C. 6erwick, Inc.
a COW company
Montezuma Slough Salinity Barrier Complex
Radial gate structure for Salinity Barrier in the
California Delta. Offsite prefabrication & float -in.
17 JANUARY 2013 Ben C. Gerwick, Inc.
1� TIDELANDS MANAGEMENT COMP ➢i EE
a COWI company
Braddock Dam
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Ben C. Gerwick, Inc.
a CON Company
Chickamauga Lock Lift -in Construction
Towing a Lift -in Cofferdam Box Segment to the Site
Ben C. Cerwick, Inc.
a CON company
Mechanically Operated Wicket Gate at Olmsted Dam
FLOW
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g x(MCC P 1 N EL. -15.15
N.w. PASS Axl5
Plate;
The wicket Gates can he raised up and
lower down 4,
1. Gantry crane (not shown for cla rity)
2. Moving actuator
3. Boat
E- - -17.12
Ben C. Gerwick, Inc.
a COWI company
Venice Storm Surge Barrier
01#I10014
1 17 JANUARY 2013
TIDELANDS MANAGEMENT COMMITTEE
Compressed air is used to
raise gates during a storm.
Gerwick performed detailed
constructability review for
this project.
iQ Ben C. CePWIck, Inc.
a COWI company
IC* Ben C. Gerwick, Inc.
a CON company
Wicket Gate (Raised)
1 TI ELAND JANUARY ANA Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT COMMITTEE
a COWI company
Wicket Gate (Raised)
Protected Side
Piles Driven "in-
the -wet"
1 17 JANUARY 2013
TIDELANDS MANAGEMENT COMMITTEE
Flood Side
Flap Gate: Steel
or lightweight
concrete
Sheet Pile Wall
Driven "in -the-
wet"
Ben C. Gerwick, Inc.
a COWI company
Wicket Gate (Stowed)
1 > ^ 17 JANUARY 2013
TIDELANDS MANAGEMENT COMMITTEE
Steel Props rest
within Hurter
Troughs
Ben C. Gerwick, Inc.
a COWI company
Inflatable Flap Gate
(Obermeyer Type)
20 17 JANUARY 2013
TIDELANDS MANAGEMENT COMMITTEE
Ben C. Gerwick, Inc.
a CON company
Schematic Obermeyer Bottom Hinge Gate
Ob4 mycrdatewith Prcp
Y 3 Ben C. CePWIck, Inc.
21 TIDELAND DELANDELAND S MAA NAGEMENT COMMITTEE
a COWI company
Flap Gate with Hydraulic Prop
zz TIDELAND Y S MAA 3 NAGEMENT COMMITTEE Ben C. Gerwick, Inc.
TI
a COWI company
Buoyant Flap Gate (Venice)
Z3 v
JANUARY 2013 Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT COMMITTEE
a CON Company
Advantages of In- the -Wet Construction
> Limited or no channel closure during construction
> Modular, floating elements lend themselves to design of the closure as an
adaptive structure
> 50 -foot wide units can be designed to built on grounded barges
Representative
construction site for
grounded barges
17 JANUARY 2013 Z e TI DELAND S MANAGEMENT COMMITTEE Ben C. CePWIck, Inc.
a COWI company
Salinity Control Advantages of Flap & Rising Sector
Gates
> Rising Sector Gates and Flap Gates rise from the bottom of the channel
> They can be partially raised during a rising tide to form a salinity barrier
against the intrusion of the dense, salt water
ZS 17 JANUARY 2013 Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT COMMITTEE
a CON company
is Ben C. Gerwick, Inc.
a CON company
Feasibility study
Newport Harbor
Floodgate Concept
> Primary goals
> Comprehensive defense system
against high tide events and other
hazards
> Key advantages over sheet -pile
walls
> Aesthetically minimally invasive
> Cost - effective with an exceptionally
low footprint
> Minimum disruption of tidal
hydrodynamics and on- demand
activation
> Proven, reliable tidal gate
technology
> Well- defined maintenance
frameworks
> Adaptive design with ample
opportunities for future upgrades
27 17 JANUARY 2013 Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT COMMITTEE
a CON company
Impact of rising tides
Flooding
and Inundations
> Major flooding events caused by
interaction between:
> Very high astronomical tides ( "King
tides "; see pictures) - Annual events
> Storm surge (storm tide) - Fairly
limited on West Coast
> Wave set -up (mostly on exposed
areas)
> Rainfall and run -off
> Sea -level rise
> Influence of change in sea -level on
total water levels may not be
neutral because of large
contribution of astronomical
component
1I ELAND JANUARY ANA � Ben C. Gerwick, Inc.
Z$ TIDELANDS MANAGEMENT COMMITTEE
a COWI company
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a
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15-
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09
SLR Contributions to 2004
glaciers and small
1965 1970
Antarctic & Creenland ire sheet
deep ocean thermal expansion
terrestrial storage
Lrface thermal expansion
1975 1980 1985 1990 1995 2000
Dace (Year)
Ben C. Gerwick, Inc.
a CON Company
SLC SLR Projections
> The indicated values are based on a
2009 report by V &R to the NAS,
where A1FI, A2 and 131 scenario -
based GCM SLR projections, are
input for the High, Medium and Low
Classes, respectively
> In line with recently issued NRC
2012 recommendations for West
Coast.
70
60
50
a
40
d ° 30
m
W 20
10
0
-.
Law `m
d
Medium _
— High m
H
1.8
1.5
1.3
1.
CO
0.8
a
0.5
0.3
0.
2030 2040 2050 2060 2070 2080 2090 2100
Year
70
60
50
a �
40
o a
d 30
m
20
10
0
EC -1
EC —II _
EC —III 6
— VR
Historical
1.8
1.5
1.3 E
1.
03
0.8 'o
a
0.5
0.3
0.
2030 2040 2050 2060 2070 2080 2090 2100
Year
30 17 JANUARY 2013 Ben C. Lerwick, Inc.
TIDELANDS MANAGEMENT COMMrrTEE
a CON company
Various Global Sea Level Rise Scenarios
7.0
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r
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2010
COPC High
■ COPC low
• CA Coastal Conservancy
— USACE /High
— — USACE / Intermediate
•••••• USACE /Low
Vermeer and Rahmstorf
Mean and Range
Note, see text on Page 3.9
for descriptions of AI F/,
A2, 81 and AR4
.000 .. .. — r
.
•. rr................ ..............
2020 2030 2040 2050 2060 2070 2080 2090
Year
i
9's.
i3t0:47
Comparison of USACE /High Projections of Sea Level Rise with the California Ocean Protection Council
(COPC) and California State Coastal Conservancy Recommendations, and Vermeer and Rahmstorf (2009), (Adopted from
Vermeer and Rahmstorf 2009)
17 JANUARY 2013 Ben C. Gerwick, Inc.
31 I TIDELANDS MANAGEMENT COMMITTEE
a CON company
NRC 2012 SLR Recommendations for West Coast
> NRC 2012 guidance
> In line with most recent projections
> Key years:
> 2030
> 2050
> 2100
> More conservative than IPCC 2007
projections
> Publications for the West Coast
> Location -based recommendations
a
> Southern Cal more exposed to SLR than
Oregon /Washington where up- thrust &
Glacial Ice Mass Loss from Alaska ^
dominate
> No mention of sensitivity of tidal events
on changes in baseline sea -level
3 17 JANUARY 2013
TIDELANDS MANAGEMENT COMMrfTEE
-124 -12'J -116
M'
4'
az• o so ,so - �• 3r wm�t" c Lcm7
URE S.1 Projected sea -level rise off California. Oregon. and Nashrngton for 2030 (blue),
en). and 2100 (pink-), relative to 2000 as a function of latitude. Solid lines are the projections,
led areas are the ranges. Ranges overlap. as indicated by the brown shading (low end of 2100 n
high end of 2050 range) and blue -green shading (low end of 2050 range and high end of 2030 rar
1= Mendocino Triple Junction. where the San Andreas Fault meets the Cascadia Subduction Zone
i@ Ben C. 6erwickr INC.
a COWI company
Timing of SLR Protection and Risk to the Community
The Current Seawalls Do Not Meet FEMA's Criteria for the 0.2%
Resiliency Case (EL over 11'); Thus Putting Restrictions on When
Homes Need to be Elevated to the 1% BFE Case (El 9').
Businesses and Homes, sold or significantly upgraded, are
Currently subjected up to a 25 0/o/yr NFIP Premium Rate Increase
Until Market Rates Are Reached. Such Rate Increases Could be
Mitigated Via FEMA's Community Rating System (CRS) If Adequate
Protection (such as a floodgate) Is Provided.
FEMA is Entitled to
Change Both the 0.2%
and
the
1%
Inundation
Projections at Any
Time, Not Only for SLR
But
Also
for
Increased
Storm and Tidal Activity. Uncertainties About Future Criteria May
Limit Current /Future Real Estate Prices Around Newport Harbor.
The Floodgate Solution May Be
California Coastal Commission,
33
Easier to Gain Approval from the
Than High Sea Walls.
Ben C. Gerwick, Inc.
a CON company
NOAA 2012 Global Sea Level Rise Scenarios
200
M
M
160
d
a
a
a
E 120
0
CD
w
80
m
J
[7
m
40
ra
m
R
0
0
0
-40
1901
1950
C)bserved scenarios
2000
Year
2050
Highest - 2.0 m
Intermediate -High - 1.2 m
Intermediate -Low - 0.5 m
Lowest - 02 m
2100
34 Ben C. Gerwick, Inc.
a COWI company
SLR and Monthly Extremes
> Some interaction exists between extreme water levels and a rise in base sea -
level.
> Historical volatility of tidal signal has increased over the past 90 years.
> A rise in the magnitude of these extreme events may add to the linear
contribution of sea -level change.
> Historical data assessment highlights the need to establish solid design basis.
m
Q
Z
t
m
'm
`m
0 — Best fit. S3
RO
9
8
6
1950 2000 2050 2100
3 J C 17 JANUARY 2013
TIDELANDS MANAGEMENT COMMITTEE
8
7
6
5
4
J
F 2 ..
0
—1
_Z
—1.6 —1.4 —1.2 —1. —0.8 —0.6 —0.4 —0.2 0. 0.2 0.4 0.6 0.8 1
Storm title
Ben C. Gerwick, Inc.
a COWI company
Combined Global SLR & Extreme Tide Heights
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• AnnualMSL
• AnnualMaxiieight
.. MSLTrend .... .----------------- _. ............... _ ......... _ ..................... .........
.
Annual Mac (Trend)
— Annual Max (p•14%)
Annual Max (p. 1 %) .. .... .. __ ....... ..._. __.._. ___._.
0
1920
1940
36 17 JANUARY 2013
TIDELANDS MANAGEMENT COMMITTEE
• • • • '�•
1960 1980 2000 2020 2040 2060 2091 2100
Year
Projections of Mean Sea Level and Extreme Tide Heights Through Year 2100
Ben C. Lerwick, Inc.
Per Everest International Consultants, Inc. aCOwlcompany
FEMA Flood Insurance Rate Map for Newport Harbor
37 v
JANUARY 2013 Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT COMMITTEE
a CON Company
Pacific Institute's Estimate of Current 1% Inundation (light blue) & Inundation with 55" of SLR (dark blue)
Inundation and Risk
38 v
JANUARY 2013 ( Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT COMMITTEE
a COWI company
DFIRM for Balboa Island With a 1% & 0.2% Exceedance
Elevation of EL +9 -ft & Over EL +11 -ft, Respectively
N1
tBNt AL
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ZCIE S .. C I� L b :. MI v ery
.ower .
39 17 JANUARY 2013
TIDELANDS MANAGEMENT COMMITTEE
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MAP SCALE 1' . !M'
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a CON Company
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a CON Company
7.8
Top of Balboa Island Seawall Survey Results
8.4. •
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;-.89 EARL AVE. 0.00 N
7,7 7.6
7,8 7.9 7.8 ST 9
V7.9 "7-S -_
i. •7.8 - 7.9
AVE. 0-00 8.3 8.3 8.0
8.4 5 8.2
-7.8 N83-2D-92 \7.8
&0 8.0,
8.4 8.5 8.5 8.5
LEGEND
LOT BOUNDARIES
STREET CENTERLINES
OUTER SEAWALL
o BENCHMARK
• STATION MARKER
•
B.0- TOP OF SEAWALL ELEVATION IN FT, NAVDBB
8.2- TOP OF SEAWALL ELEVATION IN FT. MLLW (NTDE 8301;
I F
8.6 1 . 8.6
8.7
8.9
8.7
8.8
BASE MAP PROWYDED 8Y CTTY OF NEWPORT BEACH
Top of Seawall Survev Results
40 v
JANUARY 2013 Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT COMMITTEE
a COWI Company
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8
-..- --
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8-S 8.6
7.8
9.3
8.0
9.0
8.3
8.6
9.2
9.5
9.0
8.5
8.6
8.6
8.7
8.7
8.8
8.6
9.3
9.5
8.6
8.8
9.1
8 -7
8.5
9.3 9.1
8.7
9.3
BASE MAP PROWYDED 8Y CTTY OF NEWPORT BEACH
Top of Seawall Survev Results
40 v
JANUARY 2013 Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT COMMITTEE
a COWI Company
Tide Valve Locations in Newport Harbor
Contours of ground elevation in the Newport Harbor area depicted by a DTM
based on a 2006 LiDAR survey, and location of tide valves that prevent back - flooding
through storm sewers. Note that annual inaximum high tides typically exceed 7 ft but fall
short of 8 ft relative to NAVD 88. Heights bet-ween 6 and 7 ft appear pink.
41 I a Ben C. CePWIck, Inc.
(from Flow Simulation, LLC, 2009) aCOWlcompany
Newport Beach, CA - Tidal barrier
Conceptual
Design Basis
42 17 JANUARY 2013
TIDELANDS MANAGEMENT COMMITTEE
Local Elevations, Risks of Inundation & Possible Mitigation
Possible Addition of
Asphalt Ridg
9
t
Of
Feet (NAVD 88)
- -1,245 - -500
- -500- -100
- 100 - -10
-10 -0
iiii I� 0 - 3
= 3 -6
= 6 -9
9 -12
12 - 15
- 15-18
- 18 -20
43 Ben C. Gerwick, Inc.
a COWI company
IM,
. .JC
Possible Addition of 1' to Z' High
Asphalt Ridge Near West Newport
Park (with Tapered Approaches as
Required to Accommodate Traffic)
1' to 2' High Asphalt Ridge
Beach at El +16 to +18
Ben C. Gerwick, Inc.
a CON company
Turf and Clay Top Layer Details
Used in The Netherlands
sward
stubble
(2 cm)
to rf
herbage substrate
OOts
about ^'
clay suitable for vegetation
(often little erosion resistance)
water level and frequency
(approx-------------- 1 /10 year)
erosron -sitar
clay layer
i
grass
cover
top soil
subsoil
1
core material
normal high water (NHW)
daily core
water level ZZ
undersoil
• The Core
May Be
Granular, or
Other Suitable
Fill Material.
• The
Substrate May
Be Erosion
Resistant Clay,
or Bentonite /
Soil Mixture.
top layer
Asphalt
Ridge
Lido Residential
Grass —
Sand Berms
Beachfront Whim
Vulnerability to Inundation
by storm We elevation in [8— MVD88]
I . Gate
7 9 11 12 13 14 15 1e 17
FEMA Risk Areas and Jurisdiction Line
High Risk Are A and V zones
AE �< A V AH \
Moderate Risk Areas, 'Shaded X' zone Undetermined Risk Areas. D zone
'Shaded X' zone D zone
No data available: Try the FEMA Map Service Certer ktp.11msc.fema.gov
No Flood hazard data available in Google Earth
Other information: jf/ Jurisdictions N Cross sections / FIRMs 0 LOMRs
47 v
JANUARY 2013 Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT CDMMCfTEE
a CON company
Overview of Proposed Location
48 Ben C. 6erwick, Inc.
a COWI company
Preliminary Design Considerations and Values
> Design considerations
> Current 1% Inundation EL 9' NAVD88
> Tidal Range
(MHHW: 5.2', MSL: 1.5' NAVD88)
> Sea Level Rise (Mean /Medium
Guidance: 47" by 2100)
> Local Settlement & Regional
Subsidence (limited)
> Soil Properties (use driven friction
piles for foundation)
> Nay. Channel: —900 ft. wide, 14' to
20' ft. deep, no overhead
obstructions
> Required freeboard: 1' -0" for Future
Case
49 17 JANUARY 2013
TIDELANDS MANAGEMENT COMMITTEE
Ben C. Gerwick, Inc.
a COWI company
Present
Future
Required top
15.0
15.0
of gate EL [ft]
Flood side
9.0
13.0
water EL [ft]
Protected side
6.0
6.0
water EL [ft]
Channel
-20.0
-20.0
bottom EL [ft]
Top of
foundation EL
-20.0
-20.0
[ft]
Ben C. Gerwick, Inc.
a COWI company
Conceptual 600 -ft Pass Bottom Hinge Gate Barrier
so Ben C. Berwick, Inc.
a COWI company
Comparison of 600 -ft Pass & Proposed Tidal Water -
Exchange Cross - Sectional Areas
Office and
Pump Statior
Cutoff
ME
30-
ates
Obermeyer
Cut off Slide Gate Flood
51 j Ben C. Gerwick, Inc.
a COWI company
41
Possible Obermeyer Bottom Hinge Gate
Oheiine;ei Gate::itl.5traI_
17 JANUARY 2013 Ben C. Lerwick, Inc.
52 I TIDELANDS MANAGEMENT COMMITTEE
a COWI company
Possible Wicket Gate Configuration
iup 9r :,, rr Fl .+
arft--�
FLOW
rs �
t
EL. -20.00
v ICKET
�L P1R EL- +3.00
PROP
Note:
The wicket Gates can he raised up and
lower down by,
1. Gantry crane (not shown for clarity)
2. Moving actuator
3. Boat lift buckeye
i HENCE. PIN_ EL. -22.15 \ HURTER
I 0 -
r� NAV. PA-SS AN IS -
2a -F%
ELEVATION - RAISED WICKET GATE.
53 17 JANUARY 2013 Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT COMMrrTEE
a COWI Company
Conceptual tidal barrier, open position
54 17 JANUARY 2013 Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT COMMrfTEE
a CON company
Conceptual tidal barrier, closed position
55 17JANUARY 2013 Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT COMMrfTEE
a CON company
Conceptual 400 -ft Pass Bottom Hinge Gate Barrier
56 17JANUARY 2013 Ben C. Gerwick, Inc.
TIDELANDS MANAGEMENT COMMITTEE
a CON company
Next Steps
A. Initiate Comparative Feasibility Study
> Consistent, comprehensive cost
performance comparison
> "King tides ", SLR, run -up; hydrodynamics
(tidal exchange, flushing, water quality)
> Waves, basic performance requirements
and benefits of rock armoring
> Groundwater infiltration
B. Identify Preferred Concept
C. Work with Authorities to Finalize
Concept
D. Complete Final Design
E. Bid and Construction
V
17 JANUARY 2013 Ben C. Gerwick, Inc.
57 I TIDELANDS MANAGEMENT COMMITTEE co a COWI company
A global firm with a local presence
Gerwick Office Locations
> Northern Cal.
Oakland, CA
1300 Clay St., 7th Floor
Oakland, CA 94612
Tel. (510) 839 -8972
> Dale Berner, PhD, PE
deb@gerwick.com
> Southern Cal.
Long Beach, CA
3780 Kilroy Airport Way, #200
Long Beach, CA 90806
Tel. (562) 598 -9888
> Warren Stewart, PE, SE
wnst @gerwick.com
58 17 JANUARY 2013 Ben C. Lerwick, Inc.
TIDELANDS MANAGEMENT COMMITTEE
a COWI company