Concepts and Science for Coastal Erosion Management The CONSCIENCE project, results and outcomes 12 April 2010 Marcel Marchand

Concepts and Science for Coastal Erosion Management

The CONSCIENCE project, results and outcomes

12 April 2010

Marcel Marchand


EU 6th Framework RTD

Call SSP5-A (Scientific support to policies): ‘to support the formulation and implementation of Community Policies, by providing scientific contributions to policies that are targeted precisely on needs, coherent across the various Community policy areas, and sensitive to changes in policies as they take place’.

Scientific Officer: • Dr. Karen FABBRI (till 1 April 2010)• Nicoleta-Ariana NASTASEANU (from 1 April)


Rationale

• EUROSION project: • DG Env. 2002-2004• recommendation 1: restoring the sediment

balance and providing space for coastal processes

• introduction of 4 concepts:– coastal sediment cell– favourable sediment status– strategic sediment reservoir– coastal resilience


Project partnersDeltares Research inst. the Netherlands

EUCC Mediterranean Centre NGO Spain

Coastal & Marine Res. Centre University Ireland

Int. Centre Coastal Resources Res. University Spain

HR Wallingford SME United Kingdom

Geoecomar Research Inst. Romania

Institute of Hydroengineering Research Inst. Poland

Priority Actions Programme other Croatia


Pilot sites

1: Holland coast (the Netherlands)2: Hel peninsula (Poland)3: Danube Delta coast (Romania)4: Costa Brava (Spain)5: Pevensey Bay (United Kingdom)6: Inch Beach (Ireland)


Ultimate goal of project

Make coastal erosion concepts...(resilience, sediment cells, sediment

reservoir, favourable sediment status)operational for management...(EU context, different coasts, different

management settings, ICZM, sustainability)

that is scientifically justified...(knowledge, data, models, tools)


Main challenges

Science – Policy interface:Complexity of physical

processes and social context

Uncertainty: modelsTime and space scalesEnd user involvement

Xs

R

Set-up at mean shoreline

Still Water Level

Sin b

Run-up level

Toe of Beach

hx,t

XsX

t1

t2

Setup

Time

Hswashsmax


Key issues and concepts

• Coastal resilience

• Sediment cells

• Strategic Sediment Reservoir

• Favourable Sediment Status

• Frame of Reference


Strategic objective

Tactical objective

2. Benchmarking procedure

3. Intervention 4. Evaluation procedure1. Quantitative State

Concepts

Desired state

Current state

OK?

OK?

Str

ate

gic

leve

lT

act

ica

l le

vel

Ope

ratio

nal

le

vel

WHY

WHAT

HOWWHEN

WHERE

WHO

Frame of Reference for policy implementation


Main findings• Eurosion concepts are mixture of scientific and policy

connotations• they are useful if:

– temporal and spatial boundaries are explicit– objectives for coastal erosion management are made explicit

space (km)

Time(years)

1 10 1000.1

0.1

1

10

100

Safety

Hold the line

Grow with sea

level


Hybrid concepts

• Coastal resilience

• Favourable sediment status

• Strategic sed. reservoir

• Coastal cell

system property (‘science’) equilibrium profile

strategic objective (‘policy’)

sediment budget(‘science’)

favourable for what?(‘policy’)

sediment budget(‘science’)

when strategic?(‘policy’)

sediment processes(‘science’: e.g. depth of closure)

time horizon(‘policy’)


FoR as guidance

Frame of Reference method: useful to guide erosion management

makes objectives clearshows management steps

role of knowledge becomes clearshows need for institutional arrangements

(who is responsible for what?)


Measures: Set back lines

• needed for resilience

• trade off between risks and economic profit

• risk lines requires modelling


Sand nourishments

• resilient / adaptive to sea level rise

• requires monitoring/models

• requires well established institutionalised erosion management


Hard structures

• robust / resistant

• side effects

• not adaptive to sea level rise


Erosion models

• physical scale experiments

• mathematical models

• simple reprofunctions

0

50

100

150

200

250

300

350

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5

Storm surge level above MSL (m)

Du

ne

ero

sio

n a

rea

ab

ov

e S

SL

(m

3/m

)

0

5

10

15

20

25

30

35

Du

ne

rec

es

sio

n (

m)

d50=0.15 mmd50=0.2 mmd50=0.25 mmd50=0.3 mmd50=0.4 mmd50=0.5 mmd50=1 mm

Hs,o= 4 to 8 mTp=7 to 12 s


Data and monitoring

• great variety of monitoring methods

• coastal state indicators (CSI) are key to effective monitoring programme

examples of CSI:

• dune strength

• beach width

• shoreline position


European perspective

• Implementation Eurosion concepts in Europe often hampered by lack of explicit objectives for erosion policy

• Existing EU Directives on floods, water and sea do not address the coastal erosion problem


Main conclusions

Coastal practitioners:• use Eurosion concepts and FoR as guidance• formulate CSI’s for benchmarking and

monitoring

National level:• formulate coastal erosion policies and objectives

EU level:• integrate Eurosion recommendations in EU

policies and directives


Thank You!


Coastal resilience

• Is resilience a natural state of the coast?

• What about natural receding or accreting coasts?

• Which time scales are we looking at?

• Not applicable to soft cliff coasts?!

• Resilience is not an aim in itself but a means to arrive at sustainability.


Coastal Sediment Cell

• How to delineate a CSC?

• How do CSC’s behave in time?

• Cross-boundary problems / administrative boundary does not coincide


Favourable Sediment Status

• How to define?

• Who decides what is favourable?

• Which parameters to measure?

• Which Coastal State Indicators?


Strategic Sediment Reservoir

• When is a sediment deposit strategic?

• Who decides?

• What are the consequences if sediment is considered inside or outside the reservoir?

• How to deal with distant sources (e.g. river catchments)?

Documents

Concepts and Science for Coastal Erosion Management The CONSCIENCE project, results and outcomes 12 April 2010 Marcel Marchand