Coastal vulnerability assessments for England and Wales:

the National Coastal Erosion Risk Mapping Project (NCERM)

Coastal Groups

Key drivers for better assessment:

Shoreline Management Plans and spatial planning (1995 ongoing): 100 year horizons

‘Making Space for Water’ Government Strategy (2005): adaptation and public awareness

Environment Agency ‘strategic overview of all flood and coastal risk management (2008): gaps in national assessment

National Coastal Erosion Risk Mapping

Web-based tool to complement Environment Agency Flood Map‘Comparison Report’ to highlight differences with Shoreline Management PlansHigh level statistics for local authorities

A staged approach

Stage 1 – FD2324 RACE R&D Project [April 2006]

Stage 2 – Inception Phase [July 2006]

Stage 3 – Create Baseline Position (Software and Data) [June 2007]

Stage 4 – First National Runs [December 2007]

Stage 5 – Local Validation [2009-2010]

Stage 6 – Finalise Data [current]

Stage 7 – National Coastal Erosion Risk Mapping tool [September 2011]

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Risk Assessment of Coastal Erosion (RACE) Defra project FD2324

Source: techniques for assessing unconstrained erosion and defence failure

Pathway: brings these together to establish probability within confidence bands

Receptor: analysis of socio-economic/ecological consequences

Risk Assessment of Coastal Erosion (RACE) Defra project FD2324

Judgement

Probabilistic Models

Variety of outputs, but these are only as good as the data validation and resolution

Risk Assessment of Coastal Erosion (RACE) Defra project FD2324

Robust and consistent approach;

Designed for high spatial resolution, but able to aggregate local results to inform high level assessments;

Addresses 20, 50 and 100 year horizons;

Limited to erosion but complements tools used for flood risk assessment in England and Wales;

Assesses erosion of backshore landform but may be developed further to incorporate foreshore impacts

Risk assessment combines hazard and impacts;

Risk Assessment of Coastal Erosion (RACE) Defra project FD2324

Can be reviewed in the context of SMPs to accommodate effects of adaptive responses;Inputs can range from qualitative assessments to probabilistic models and a range of assumptions/scenarios can be tested;Considers climate change through sensitivity testingAssesses uncertainties such as erosion ‘catch up’ after defence failure.Hierarchy of analytical methods allows proportionality of assessment according to risk, scale and data availability;

Stage 2: Inception and consultation

End-User ConsultationInitial best estimate of erosion rates

Editing and review at local level

Developing a web-based interface for testing

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Stage 3: Create baseline position

Spatial DataOS MasterMapAerial Photography (EA Twerton)

Recession DataFuturecoast

Defence DataNational Flood & Coastal Defence DatabaseBespoke LA Data

Key Statistics produced6,256km of coastline (England and Wales)

• 2,900km (46%) at risk from erosion• 2,354km undefended• 546km defended

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Stage 4: First national runs

First National Coastal Erosion ‘Maps’ using two scenarios

• No Defences• No Active Intervention

National Data LimitationsDefence Data

• 39% defended coastline could not produce any results

Recession Data• Futurecoast was a high-level study

Spatial Data• National aerial photography dataset out of

date

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Stage 5: local validation

Local Validation #2Validate initial coastline position

Validate defence data

Validate recession information

Re-run RACE Model

View indicative results

Provide feedback

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Stage 5 cont’d: local validation tool

Stage 6: Final validationTo ensure local authority officers are satisfied with the accuracy of final outputsFacilitated by local authority ‘champions’ and Environment Agency regional project leads

Final outputs will be released from September 2011, starting with two ‘pilot Shoreline Management Plan areas in the NE and south.

Coastal Groups

How do we show the risk from erosion?PROFESSIONAL PRODUCTS:

2 scenarios within the GISNo Active Intervention ‘baseline’ scenarioSMP2 policies factored in

Erosion predictions for 3 epochs:0 – 20 years20 – 50 years50 – 100 years

3 confidence bands for each epoch5%50%95%

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PUBLIC-FACING INFORMATION:

1 scenario displayedSMP2 policies factored in

Erosion predictions for 1 epoch:0 – 20 years

Upper and lower percentile confidence limits quoted as a range

5%95%

Fundamental disagreement

Zoomed out is more representative of the level of confidence in the data

The professionals recommend..... What the public want.....

Zoomed in the only thing they felt was useful. They’re not interested in regional abstractions, but want to know about their house.

Coastal Groups

Coastal Groups

Complex information

Epochs

Range of erosion rates / confidence bands

ScenariosUnrealistic impression of certainty

Doesn’t reflect what really happens

Interactive web tool chosen instead…

Concerns about existing presentation

NOTE: dummy data only. This is a test example for presentation purposes only and is likely to change prior to publication

NOTE: dummy data only. This is a test example for presentation purposes only and is likely to change prior to publication

“We are improving our understanding of coastal erosion using local knowledge and the best available science, and raising awareness now, so that we can all adapt together to our changing coast…”

Coastal Groups