FRM02Broad Scale Ecosystem Impact Modelling (BSEIM) Scotland

Trevor WadeCascade Consulting

Background to BSEIM

Defra/EA joint R&D programme on flood and coastal defence:• FD2108 (2002) Scoping Study outlining future research and

development to support Broad Scale Ecosystem Impact Modelling (BSEIM)

• FD2112 (ongoing) BSEIM Toolbox 1• Consolidated guidance for practitioners in sustainable flood

management • Systems and evidence-based approach for ecosystem

assessment • Establish and demonstrate a ‘toolbox’ containing best practice

procedures in data collation and ecosystem impact prediction using currently available data/ techniques at the broad scale

• Fluvial and estuarine/coastal systems

BSEIM ScotlandOverview

BSEIM Scotland provides a framework and methodological “tools” for assessing ecosystem impacts from flood management (and potentially other policy) decisions at a catchment and coastal/ estuarine cell scale.

BSEIM ScotlandIncludes:

• Broad-scale • Existing datasets• Established, emerging and novel methods• Identification and collation of existing

ecosystem objectives• Evidence-based with expert interpretation• Appropriate consultation on data interpretation

and ecosystem objectives• Targeted to study objectives

BSEIM ScotlandDoes not:

• Provide new data• Interpret at reach or scheme level• Focus on species or designations• Identify flood risk areas

Methodology Stages

Identify study area

Consultation/review through stakeholder forum

Use EcoAC to develop/assess activities

Map & tabulate Broad-scale Ecosystem Assessment Criteria (EcoAC)

Develop understanding of broad habitat & ecosystem drivers

Identify biodiversity opportunities & constraints

Broad Habitat & Ecosystem Drivers

Freshwater systems Coastal/ estuarine systemsChannel condition• In-channel habitats and ecology• Catchment hydrology/hydrogeology• Geomorphology:

• Sediment supply, transport and deposition

• Channel modification

Baseline habitats• Sedimentary habitats• Hard substrate habitats• Inland habitats (especially freshwater/

brackish habitats)Shoreline migration• Coastline erodability• Barriers to coastal erosion• In-shore habitats affected by erosion

Floodplain connectivity• Extent of riparian zone• Active ecological riparian habitat • Potential areas for riparian habitat

enhancement

Tidal inundation and coastal flooding • Extent of littoral and super-littoral zones• Extent of flooding influence on habitat

qualityChannel continuity• Barriers to river continuity Mobile sediment availability

• Mobile sediment type• Sediment budget• Barriers to sediment mobility

Case Study of BSEIM for Flood Management Policy Development in

the River Dee Catchment

1. River Dee Catchment

BanchoryBallater

Tarland

Aberdeen

0

20 km

River Dee Braemar

Tarland Burn Aboyne

Ordnance Survey 1:250.000 used under license from SEGIS

Geldie Burn Water of FeughRiver MuickRiver Dee

2. Channel Condition Basedata

Map Title Dataset Scottish toolbox resource

A Hydrogeology BGS hydrogeology NRFAB Substrate erodability BGS drift geology NRFAC Channel gradient Channel gradient index FEH or NextMapD Landscape sediment

sourcesLandscape sediment index

CEH LCM2000

E Channel modification Habitat modification index

RHS

F On-line flow constraining features

In-channel structures Asset register, OS

Standing water CEH LCM2000G Surface run-off potential Run-off potential index CEH flow grid

Landscape sediment index:

Unmanaged/ managed pasture Coniferous woodland River channelsTilled land Mixed woodland

Urban areas Commercial forestry

2D. Landscape Sediment Sources

0

20 km

CEH Land Cover Map 2000 used under license from SEGIS; CEH River Channel Network used under license from SEPA; Forestry Commission owned land provided by Forestry Commission and used with permission.

Sediment sources:Forestry

Sediment sources:Tilled land

Tarland Burn,middle catchment

Lower Tarland Burn,looking upstream in Aboyne

2E. Channel Modification

0

20 km

Habitat Modification Class: Other:Pristine River

channelsSemi-naturalPredominantly unmodifiedObviously modifiedSignificantly modified

134 Pristine33 Semi-natural8 Predominantly unmodified17 Obviously modified1 Significantly modified

River Habitat Survey data provided by SEPA

Water of Tanar/ River Dee confluence, looking upstream from Aboyne

Bar vegetated by trees, River Dee mainstem, looking upstream from Aboyne

River Dee mainsteam bank protection, looking upstream near Aboyne

3. Floodplain Continuity Basedata

Map Title Dataset Scottish toolbox resource

A Floodplain areas and existing defences

Indicative floodplain maps Mapped aerial photography, SEPA indicative flood outlines

Flood embankments (major/minor)

Scottish coastal defence and asset database

Embankments and other constraints

OS

B Active ecological floodplain

Habitats in the riparian zone Aerial photographyWetland surveys

C Landcover in potential floodplain areas

Land cover index CEH LCM20000

3A. Floodplain Areas andExisting Defences

Flood risk Other:Indicative River

channelsflood outline

Existing flood defences

0

20 km

Middle Tarland Burn

Flood outlines provided by Aberdeenshire Council from digitised aerial photography of 11/2002 floods; Scottish costal defence and asset database used with permission of Scottish Executive

Flood riskIndicative flood outline

3A. Floodplain Areas in the middle Tarland

Ordnance Survey 1:50.000 used under license from SEGIS

Elevation:

120 130 140 150 160 170m AOD

3A. Floodplain Areas in the middle Tarland

NextMap DTM used under license from SEGIS

3A. Floodplain Areas in the middle Tarland

3A. Floodplain Areas in the middle Tarland

3C. Land Cover in the middle Tarland

Land cover index:Semi-natural Agricultural Water dependent habitatsScrub/ heath/ woodland Arable Fen/ marsh/ swamp

Grassland Grassland BogMontane habitats Standing open

water

4. Channel ContinuityBasedata

Map Topic Dataset Scottish toolbox resource

A Features potentially constraining ecological movement

Dams, weirs, locks, gates OSStanding water CEH LCM2000

5. Designations and Targets

Map Topic Dataset

A European nature conservation designations

• Special Area of Conservation (SAC)• Special Protection Area (SPA)• RAMSAR convention site

National nature conservation designations

• Site of Special Scientific Interest (SSSI)• National Nature Reserve (NNR)

Catchment Targets• NE Scotland Local BAP Action Plan• River Dee Catchment Management Plan• Natural Heritage Futures

• Fisheries targets• Hydromorphology improvement targets

Constraints & Opportunities

Protection• Maintain geomorphologically active features • Maintain lack of flow regulation in catchment • Maintain suitable coarse sediment delivery• Maintain velocities for coarse sediment transport on

mainstem• Maintain floodplain connectivity where ecologically sound• Prevent construction of barriers to migrationEnhancement• Take opportunities to reduce fine sediment imbalance• Take opportunities to attenuate run-off • Increase floodplain connectivity and enhance biodiversity

benefit

Map & tabulate Ecosystem Assessment Criteria

7. Protect floodplain connectivity

2. Attenuate surface water run-off

10. Re-connect floodplain

5. Protect floodplain connectivity

9. Re-connect floodplain

12. Barrier to migration (weir)

13. Barrier to migration (lock)

14. Barrier to migration (tidal barrage)

8. Enhance floodplain connectivity for sediment transfer

4. Enhance channel to maintain sediment supply and passage

3. Reduce channel capacity

1. Maintain unmodified channels of good diversity in upland sub-catchments

6. Protect floodplain connectivity

11. Re-connect floodplain

Legend:

Derwent catchment boundary

River channel

Urban area

Broad-scale Ecosystem Criteria (listed by number)

Protection

Enhancement

CEH River Channel Network used under license from Environment Agency

Potential Applications

• Appraisal of the wider catchment/ coastal cell implications associated with individual flood management schemes

• Assessment of the ecosystem implications of sustainable flood management policy at the catchment/ coastal cell scale

• Provides an evidence base for the development of programmes of measures for activities (including flood management) included in the Water Framework Directive, and a framework for their relative assessment

Summary of Project Output

• Project report:• Methodology development• River Dee catchment case study

• Methodological guidance • Presentation pack

The final outputs will be published on SNIFFER’s website atwww.sniffer.org.uk during November 2005