SUBGROUP 6 NAVIGATION STRUCTURES AND · PDF fileSUBGROUP 6 NAVIGATION STRUCTURES AND CHANNELS...
Transcript of SUBGROUP 6 NAVIGATION STRUCTURES AND · PDF fileSUBGROUP 6 NAVIGATION STRUCTURES AND CHANNELS...
SEA LEVEL CHANGE WORKSHOP
SUBGROUP 6
NAVIGATION STRUCTURES AND CHANNELS
3 December 2010
Washington, D.C.
• Subgroup Overview
• Tools and Models
• Design Considerations
• Example Projects
• Challenges and Issues
TOPICS
NAVIGATION
OVERVIEW
SUBGROUP 6: NAVIGATION
STRUCTURES AND CHANNELS
• Steven Gill
• Crane Johnson
• David Kriebel
• Michael Mohr
• Heidi Moritz
• Julie Rosati
• Thomas Smith
• NOAA
• USACE, POA
• USNA
• USACE, LRB
• USACE, NWP
• USACE, CHL
• USACE, POH
5
MikeHeidi
Tom
SUBGROUP 6
Steve
Dave
Julie
Crane
NAVIGATION SUBGROUP 6
FOCUS AREAS
Appendices:
Action
Appendix 1. References
Appendix 2.
Data Requirements, SLC Equations, and Development of
SLC Curves Group 6
Appendix 3. Project Performance Modes Group 6
Appendix 4. Planning Process
Appendix 5. Engineering Process
Appendix 6. Impacts and Responses: Models and Analysis Techniques Group 6
Appendix 7. Display and Communication Tools
Appendix 8. Regional and Project Type Examples Group 6
NAVIGATION STRUCTURE
MATRIXPROJECT PHASE SEA LEVEL RISE (SLR) SEA LEVEL FALL (SLF)
PLANNING •ADDRESS SLR IMPACTS DURING THE PLANNING PHASE.•ADDING TO CREST HEIGHT AND ARMOR STABILITY SHOULD BE INCORPORATED UP FRONT.•N.E.D. ANALYSIS MAY NEED TO BE REFINED FOR SLR EVALUATION.
•DECREASING DESIGN LOADS FOR MOST OF STRUCTURE THROUGH PROJECT LIFE-CYCLE.
•PREVIOUSLY SUBMERGED PORTIONS OF THE STRUCTURE MAY EXPERIENCE INCREASED LOADING.
DESIGN •PROJECT ENGINEER WILL HAVE TO FOLLOW APPROPRIATE SLR GUIDANCE.•SLR CONSIDERATIONS FOR DETERMINING ARMOR STONE WEIGHT , CREST ELEVATION, STRUCTURE LENGTH, ETC...•ASSOCIATED PROJECT FEATURES.
•DECREASING DESIGN LOADING THROUGH THE PROJECT LIFE-CYCLE.
•PROJECT ENGINEER MUST ADDRESS POSSIBLE CHANGES IN FOUNDATION CONDITION.
CONSTRUCTIONO&M
MONITORING
•DEPENDENT UPON PLANNING AND DESIGN PHASE APPROACHES.•IF NOT ADDRESSED EARLIER, ADAPTIVE MANAGEMENT MAY NEED TO BE IMPLEMENTED.•DETAILED MONITORING PLAN MUST BE IMPLEMENTED TO QUANTIFY THREAT.•SHRINKING O&M BUDGET MAY PRECLUDE NECESSARY MODIFICATIONS.
•MONITOR AND DOCUMENT SLF AND REACT APPROPRIATELY.
NAVIGATION CHANNEL
MATRIXPROJECT PHASE SEA LEVEL RISE (SLR) SEA LEVEL FALL (SLF)
PLANNING •MINOR IMPACT TO DREDGING REQUIREMENTS.•SHOALING MAY BE AN ISSUE (LOCATION/VOLUME).•CONSIDER ADAPTIVE MANAGEMENT APPROACHS.
•FUTURE DEEPENING COSTS MUST BE INCLUDED IN PLAN FORMULATION.
•ECONOMIC JUSTIFICATION MUST INCORPORATE ALL ASSOCIATED COSTS.
DESIGN •MINOR IMPACT TO DREDGING REQUIREMENTS.•SHOALING MAY BE AN ISSUE (LOCATION/VOLUME).•CONSIDER ADAPTIVE MANAGEMENT APPROACHS.
•PROJECT ENGINEER MUST IDENTIFY TYPES OF MATERIAL TO BE DREDGE AND COST MUST BE QUANTIFIED.
•SIDE SLOPES MUST NOT ENCROACH ON ADJACENT PROJECT FEATURES.
CONSTRUCTIONO&M
MONITORING
•DEPENDENT UPON PLANNING AND DESIGN PHASE APPROACHES.•IF NOT ADDRESSED EARLIER, ADAPTIVE MANAGEMENT APPROACH COULD BE IMPLEMENTED AS NEEDED.•DETAILED MONITORING PLAN MUST BE IMPLEMENTED TO QUANTIFY THREAT.
•CONSIDER WAITING UNTIL THIS PHASEOF THE PROJECT TO ADDRESS SLF ISSUES.•MONITOR AND DOCUMENT SLF AND REACT APPROPRIATELY.•WHERE SHOALING IS MINIMAL, DREDGING MAY NEED TO BE ACCOMPLISHED SPECIFICALLY TO KEEP UP WITH SLF.
NAVIGATION
TOOLS AND MODELS
Julie Rosati
Coastal & Hydraulics Laboratory
Analysis Tools and Modeling Techniques
for SLC:
Navigation Structures and Channels
What are Problems and Processes
related to Navigation and SLC?1. Waves on structures and inside harbors:
a) Water level elevation affects where waves break on structures
b) …heights of waves at structuresc) Waves and water elevation affects navigation in harbors
2. Sediment transport , as a function of waves and currents:a) Change in where sediment shoals in channelsb) Adjacent beach erosion/accretionc) Flocculation of fine-grained clays/silts with change in salinity
intrusion3. Waves and water levels in harbors/estuaries affect capacity of
dredged material placement sites (subaerial and subaqueous)4. Navigation constrained due to elevation of bridges and port
infrastructure relative to water levels
Jetties and Navigation Channels
Barrier Island
MWL1
MWL1
SL1
MWL2
MWL2
SL2Sand Transport
• Wave forcing on structures
• Sand transport over jetty; breaching of land near the jetty (flanking)
• Extreme ship motion in harbors (waves and currents)
Navigation Depth and Shoaling
• Increase/decrease in navigable depth
Present MLW
Future MLW
• Change in shoaling magnitudes and locations
• Salinity intrusion increased/decreased into estuary (changes shoaling patterns if fine-grained flocculation is a concern; environmental consequences)
Dredged Material Placement Sites
• Sub-aerial sites may experience changed capacity and increased waves
• Underwater disposal sites may experience increase or decrease in capacity
Jamaica Bay, NY
Bolivar Marsh, TX
Navigation Infrastructure•Clearance under bridges
reduced
•Port and harbor infrastructure may need to be rehabbed
Tier 2: May be useful
for SLC Assessments
Detailed Functional
Analysis
Tier 1: Must-have for SLC
Assessments Screening-Level Analysis
Tier 3: Not normally
useful, but may be for some cases Environmental
Issues
Analysis Tools and Modeling Techniques
for SLC:
Navigation Structures and Channels
Tier 1: Must-have for SLC Assessments
Analysis Tools and Modeling Techniques
for SLC
a) Waves at structuresb) Overwash/overtopping/transmission at structuresc) Navigation constraints by vessel type
CEDAS: Coastal Engineering Design and Analysis System
Screening-level tool to assess whether more detailed assessment is required
Tier 2: May be useful for SLC Assessments
Analysis Tools and Modeling Techniques
for SLC
Waves; Wave-Structure interactionSMS; Bouss2D (detailed applications); CMS; CGWAVE (harbors); PTM; STWAVE
Wave-Current-Circulation-Sediment TransportSMS; CMS; ADCIRC-STWAVE-CMS; PTM; FATE
Tidal CirculationSMS; ADCIRC; CMS; ADH; PTM; CH3D
Ship Navigation CADET; ANKUDINOV; SQUAT
Tier 3: Case-specific applications
Analysis Tools and Modeling Techniques
for SLC
Environmental issues (salinity, water quality)SMS; CH3D; ADH; PTM; CE-QUAL
Adjacent beach integrity; adjacent beach nourishmentGENESIS; GENCADE; BEACH-fx; SBEACH
Groundwater issues with salinity/contaminants SMS; GMS; GSSHA; WASH123D
NAVIGATION
FLOW CHART DEVELOPMENT
Crane Johnson
Alaska District
Questions regarding EC 1165-2-211
Are their situations where we expect MSL, MHW and MHHW trends to be significantlydifferent?
How should the std error of the linear trends for MSL, MHW and MHHW be utilized?
Calculating a risk impliesthat we can estimatethe probability of occurrence for each scenario.
Navigation Structures and Channels Project
Existing
ProjectNew Project
Formulate Alternative assuming historical rate of relative sea level change
(including Without Project Conditions)
Screen Alternative forIntermediate and High SLC Scenarios
Functional requirementsmet for all SLC scenarios
or alternative isadaptable for
all SLC scenarios
Formulate alternative for intermediate and high SLC scenario. Developproject impacts (cost and benefits) and qualitative risk for both scenarios.
Yes
ContinuePlanning Process
Large Project
No
Yes
Use the historical trend for alternatives analysis
with adaptive strategies identified for intermediate
and high scenarios
Can alternative be modified to provide for future adaptation to
changes in sea level?
YesNo
No
Screen Alternative for
Intermediate and High SLC Scenarios
1. Evaluate the alternative by estimating future conditions and checking these against performance modes or functional requirements under the intermediate and high sea level change water levels. This step is primarily performed using professional engineering judgment and simplified analysis.
2. Identify feasible adaptation methods for alternative under the intermediate and high sea level change scenarios.
Formulate alternative for intermediate and high
SLC scenario. Develop project impacts
and consequences for both scenarios.
1. Formulate the alternative for the intermediate and high sea level change scenarios. Utilizing the base (historical) formulation vary the design water levels to evaluate sea level change scenarios. This will include a determination of the costs and benefits associated with each scenario.
2. Identify and include feasible adaptation methods in the alternative formulation for the intermediate and high sea level change scenarios.
3. Utilizing the quantitative consequences for each SCL scenario provide a qualitative consequences that will be included in the alternatives comparison and selection.
MLLW
Sto
rm S
urg
e
Vertical Land Movement
Sea Level Change
Un
cert
ain
ty
Un
cert
ain
ty
Design Water Level
Un
cert
ain
ty
POA Revetment Design Water Level
Un
cert
ain
ty
High Tide
?
NAVIGATION
DESIGN CONSIDERATIONS
Heidi Moritz
Portland District
SLC PRESENTATION: GROUP 6 NAVIGATION STRUCTURES AND CHANNELS
Slide 27
Checklists that would be helpful when assessing sea level change impacts to navigation structures and channels
Factor (From EM 1110-2-1404, Bold are additions)
Factor affected by water level
change? CommentMAYBE / YES NO
Fleet vessel
a. Dimensions X
a. Maneuverability and speedX
Manueverability doesn’t change, but as environmental factors
change, need additional navigation simulation modeling as vessel
trackline could change
a. Channel frequency of use X May not be able use channel as often.
Weather and Hydraulic
a. Waves X
a. Wind X
a. Currents (tidal and or river) X
a. Tides X
a. Salinity X
a. Visibility (Fog, rain, snow) X
a. Ice X Location of ice dunes and other features may change.
Physical
a. Sediment sizes and areal distribution in channel, regions
of serious shoalingX
Shoaling pattern change.
b. Geology (rock or soft bottom) X Need to ensure data coverage for affected project features
c. Hydrography x
d. Dredge Disposal Areax
Temporal dredging quantity changes will result in different
project dredge placement volume
e. Obstructions x
Environmental X
Real EstateX
Project footprint may need change with existing projects (O&M)
or for new projects, may need to obtain additional easements for
future needs.
Legal (Project authorization) x
Navigation Project Purpose and Goals
Slide 28
• Provide a navigable entrance to harbors and inland navigation• Wave and current protection• Navigable depth
• Protect harbor and backshore areas as identified
• Provide a stable and environmentally acceptable project layout• Sustainable structure maintenance • Sustainable dredging and disposal operation • Inner and outer shoreline stability• Updrift and downdrift shoreline stability• Acceptable coastal processes changes
Key Questions
Slide 29
• What elements of the navigation project may be sensitive to SLC?
• What types of impacts could occur? (structures, operations, performance)
• What level of analysis is merited given the expected impacts?
• Which parts of the navigation project might be adaptable? Which parts would not be?
• How might adaptive management be applied to this project?
• What coastal or estuarine processes may be impacted?
What do Corps field offices need to do differently?
Slide 30
• General
• Be knowledgeable about different data requirements. • Consider design and performance categories which may be
affected. • Develop a plan to conduct sensitivity analysis using 3 curves.• Identify if SLC would have a cumulative effect with other climate
change factors.• Identify tipping points in analysis or project performance.• Identify potential range of SLC responses (structure response,
wave transmission, shoreline/infrastructure damage, channel shoaling and maintenance)
• What would be expected to happen without planning/designing for SLC?
• Are changes in coastal processes or environmental conditions expected?
What do Corps field offices need to do differently?
Slide 31
• Planning Stage Investigation• Assess potential impacts over 25-, 50-, and 100-year planning horizons over 3 sea level change rate scenarios. (additional planning steps)• How might the project be designed / layed out to be more adaptive? • How might maintenance requirements change over time? What monitoring activities will be required and at what times?• What would be expected to happen without planning/designing for SLC?
What do Corps field offices need to do differently?
Slide 32
•Evaluation of Existing Project• Assess potential impacts over 25-, 50-, and 100-year planning horizons over 3 sea level change rate scenarios. • How might maintenance requirements change over time? What monitoring activities will be required and at what times?• Are changes in authorization language required?• Is there a need for additional or secondary structures to improve the long-term stability of the project? (spur groins, backshore protection, etc.)• Is there a need for changes to the channel (depth, width, etc.)?• Will changes in maintenance or operational practices be required?
General Performance Categories
Slide 33
• Wave transmission – channel and interior to harbor• Diffracted• Overtopping• Permeability
• Erosion/Backshore Protection• Structure foundation• Shore tie-in• Inner channel/harbor• Updrift and downdrift
• Sediment movement and channel shoaling
• Harbor/estuary processes• Resonance• Salinity• Current velocities
Typical Design Categories
Slide 34
• Project layout design (structure location, length)
• Structure type (flexible/rigid, rock/concrete)
• Vertical structure stability
• Cross section configuration design (crest elevation, crest width, side slopes)
• Armor stability equations (front- and backside)
• Toe protection design
• Damage and maintenance calculations
• Runup, overtopping and transmission equations and analyses
• Shoaling projection analyses
• Harbor resonance evaluation
• Navigation channel dimensions and requirements
• Environmental parameters evaluation
Benefits and Costs
Slide 35
• Costs:• Original construction• Adaptations to structures (damage - or erosion-generated)• Secondary structures (spur groins, backshore protection, etc.)• Emergency management & response• Dredging (quantity, frequency)• Dredged material disposal• Environmental impacts – salinity, habitat change, inundation
• Benefits• Vessel operational windows• Vessel damages• Prevented shoreline and infrastructure damages• Prevented backshore/harbor damage• Prevented dock/pier damage
NAVIGATION
EXAMPLE PROJECTS
KIVALINA
ALASKA
TIDE RECORDS
Figure 1. Data from Proshutinsky et. al (2004) contains information about relatively close long term tidal monitoring stations in Eastern Russian. This information provides some background on the regional trend in the Chukchi Sea.
SEA LEVEL CURVES
Figure 2. Estimated eustatic sea-level rise at Kivalina Alaska. Due to lack of local data, this estimate does not include the relative effects of local uplift, subsidence, or storm surge.
DREDGED MATERIAL
CONTAINMENT DIKE
Example of Impact to Coastal StructureDredge Material Containment Dike
Typical of mid-Chesapeake Bay
Storm Tide
Wave Runup
Water Depth at Toe
Wave RunupDependent on wave height at toe, H
Wave height dependent on water depth at toe, ds
From CEM for shallow water breaking waves
Hmob = 0.6 ds
Wave Runup on RevetmentsRock-Armored Slopes
low permeability
Runup Function of Surf Similarity Parameter
om = tan / sqrt(Hmob/Lom)
SLR allows larger waves to
impact structures, increasing
runup
Chesapeake Bay Containment Dike
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
-100 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100
Years from present
Tid
e L
ev
el a
bo
ve
ST
ND
(ft
)
Typical elevation of
revetment for
Chesapeake Bay
containment dikes +11 ft
MLLW or +15.5 ft STND
MSL trend USACE
Intermediate Scenario
Storm Tide
35 year return period
Storm Tide plus Runup
without recomputing wave
heights
Storm Tide plus Runup
recomputing wave heights
Storm Tide
Wave Runup
Increase in wave runup due to larger
waves at toe of structure
KAHULUI HARBOR
KAHULUI HARBOR
KAHULUI HARBOR
NAVIGATION
HELP!!!
Tom Smith
Honolulu District
• EXAMPLE PROJECTS FOR ETL
• APPROVED NAVIGATION REPORTS THAT HAVE INCLUDED SLC EC REQUIREMENTS
• NEED TO PULL TOGETHER ALL THE MATERIAL THAT HAS BEEN DEVELOPED TO DATE
• COORDINATE WITH OTHER SUBGROUPS (i.e. Coastal Storm Damage Reduction)
• TIDAL DATA STUDY (TDS)
CHALLENGES AND ISSUES
THANK
YOU