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