SLIDE 1
Woodbrook Landfill
- Historic Landfill along 300m of coastline
- Eroding coastline 0.3m/year
- Oversteep cliff
- Landfill material is falling from the cliff face
- nto the beach at Woodbrook
2 Woodbrook landfill Rev A 09/05/2018
Woodbrook Landfill Coastal Protection And Cliff Stabilisation - - PowerPoint PPT Presentation
Woodbrook Landfill Coastal Protection And Cliff Stabilisation - - PowerPoint PPT Presentation
Woodbrook Landfill Coastal Protection And Cliff Stabilisation Preferred Emerging Solution Woodbrook Landfill Historic Landfill along 300m of coastline Eroding coastline 0.3m/year Oversteep cliff Landfill material is falling from
SLIDE 2
SLIDE 3
Coastal Protection - Need
- Ongoing erosion – 0.3m/year
- Cliff instability – Over-steep Cliff
- Historic Landfill Site
- Prevention of historic landfill material entering
the sea
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SLIDE 4
Woodbrook Landfill
- Coastal Protection
– Reduce ongoing Cliff Erosion
- Cliff Stabilisation
– Prevent Cliff Failure
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SLIDE 5
Landfill Site
- Historic – pre 1968
- Mostly builder’s rubble
- Top 2m to full height
- Contaminant Levels Low
- Tier 2 Assessment
- Remedial Measures Appraisal
Woodbrook landfill Rev A 5 09/05/2018
SLIDE 6
Landfill Site – Recent Assessments
- Tier 2 Risk Assessment - FT
- Appraisal of Remedial Measures - FT
– Construction materials and some ACM – Risk from leachate is low – Leave material on site – Prevent further loss of material into sea
- Coastal Protection Measures - MWP
– Reinforced concrete seawall – Sheet piling – Full height revetment – Revetment to cliff toe with cliff stabilisation
- Preliminary Design
– Revetment options
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SLIDE 7
Preliminary Design
- Full Height Revetment
- Revetment to cliff toe and regrade face of
upper cliff to stable slope
- Sediment sampling and Analysis
- Preferred design
– Revetment to cliff toe and regrade face of upper cliff is feasible
Woodbrook landfill Rev A 7 09/05/2018
SLIDE 8
Preliminary Design
09/05/2018 Woodbrook landfill Rev A 8
SLIDE 9
Preliminary Design
- Key Quantities
– Primary Armour:9,000m3 – Underlayer:4,500m3 – Mattressing: 600m2 – Cliff regrading: 5,500m3
Woodbrook landfill Rev A 9 09/05/2018
SLIDE 10
Preliminary Design
- Programme
– 4 to 6 months
- Source of materials
– Primary armour
- Access to Site
– By Road
Woodbrook landfill Rev A 10 09/05/2018
SLIDE 11
Assessments
- Conservation architecture
- Archaeology
- AA screening
- Coastal Processes
09/05/2018 Woodbrook landfill Rev A 11
SLIDE 12
Conservation Architecture
- Railway Bridge Abutments
- Historic Railway Seawall
- The abutments are within the footprint of the
proposed works
- The abutments will be lost whether or not the
works proceed.
09/05/2018 Woodbrook landfill Rev A 12
SLIDE 13
Archaeology
- Railway structures
- Historic forest
- Avoid if possible
- Preserve by record if not
- Monitor construction works
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SLIDE 14
AA Screening
- Assesses potential impacts on SAC/SPA
- No significant adverse impact
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SLIDE 15
Coastal Processes
- Extreme water levels – 2%AEP
- Extreme wave conditions – depth limited
- Shingle and cobbles on upper shore
- Sand on lower shore
- Sediment transport analysis
- Potential impacts:
– Lack of material for sediment budget – 4% – Increased erosion immediately north - localised
09/05/2018 Woodbrook landfill Rev A 15
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