What can we learn from the River Axe – an award winning project

Sun Yan Evans – Mott MacDonald Andy Emblin – Environment Agency Outline

1. Introduction 2. River Axe catchment 3. History of flooding 4. Project set up & funding 5. Project governance 6. Tiered approach & efficiency 7. Key ingredients for success Introduction R. Yarty River Axe catchment

R. Axe

96km2 178km2 Key features

R. Yarty

R. Axe

Axminster History of flooding – Chard Junction

31/12/2000 19/12/1992

29/11/1965 07/07/2012 History of flooding – Broom

13/10/1993 13/10/1993

7/12/2000 30/11/2012 Key recent event: 7th July 2012 storm 7th July 2012 event

Chard Junction

Broom

Weycroft

Axminster

Whitford Damages from 7th July 2012 event All three parties affected

EA

Network Rail

DCC Response from organisations affected

• EA – A more evidence-based understanding of present day flood risk

• Network Rail – To enable better management of future flood risk, develop asset resilience

County Council – To assist future planning of flood risk management Project set up & funding

Common interests: to improve understanding of flood risk, to tackle challenges and issues for greater & wider benefits

Project set up Partnership Collaborative funding working Project governance

Senior Users Senior Supplier Advisory Group (Legal, procurement) Project Board

Project Product Director Owners

Stakeholder Working Group Project Team (Chair: EA PM) Joint development of project scope

We understand each other’s needs & requirements, impacts and benefits Tiered approach to bring further efficiency Flood risk assessment - approach • 2D model Ü • Multiple events • Multiple scenarios • Flood progression • Depth, velocity, hazard

2013 Channel Survey • Wider use Extent of 2D domain 1m LiDAR Elevation (mAOD) 250m

– WFD 10m

SAR Elevation (mAOD) – Option testing 170m

0m

0 0.75 1.5 3 Kilometers Asset Vulnerability: Key sections at risk of flooding Railway Road Chard Junction Station Road, Chard Junction

Broom Crossing Broom Lane Axe Farm

Weycroft Weycroft Bridge

Millbrook Stream White Bridge

Shand Park B3261 Bow Bridge

Whitford

Whitford Road Volumes > 25,000m3 stored behind railway Key achievements for Tier 1

• Better Understanding of: – Flood Risk – Critical risk locations – Magnitude of vulnerability – Present day hazard • Built the evidence for further actions • Develop a model for wider use in the future What happened after Tiers 1, 2 & 3?

• Develop scoping plan for next phase • Option development & testing • Narrow down options • Consultations • Preferred options selected • Schemes under implementation

EA Project Excellence Award 2016 Summary - key ingredients for success

Leadership Vision Partnership

Commitment

Knowledge

Thank You

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