ClimateClimate ChangeChange andand thethe ImplicationsImplications forfor thethe ManagementManagement ofof CoastalCoastal LandslidesLandslides

JamesJames HoughtonHoughton SeniorSenior GeotechnicalGeotechnical EngineerEngineer IsleIsle ofof WightWight CouncilCouncil Outline • Background to landsliding on the • Current management strategies • Specific projects aimed at reducing landslide risk TheThe IsleIsle ofof WightWight CoastlineCoastline --ComplexComplex andand VariedVaried TheThe UndercliffUndercliff The Undercliff

12km 500m Simplified Landslide Model LandslipLandslip atat BonchurchBonchurch LossLoss ofof RoadRoad atat NitonNiton GIS Map Data, Ventnor Undercliff

Ordnance Survey Base map

Aerial photograph Landslide Susceptibility in the Undercliff Mean Monthly Effective Rainfall Change Scenarios at Ventnor

From Halcrow, 2001 IWCCE Key Responsibilities

• Shoreline Management & Coast Protection • Coastal, landslide and cliff monitoring and management • Ground stability engineering • Planning liaison over coastal, geotechnical and environmental issues • Harbour management • Dissemination of information and public relations through the Isle of Wight Coastal Visitors Centre Isle of Wight Undercliff Landslide Management Strategy

Undercliff Landslide Management Strategy (since 1992)

Management Committee

Planning control Building control Engineering Monitoring measures

Planning guidance Codes of good Coastal Forecast map practice protection

Drainage Early warning

Loss mitigation Isle of Wight Undercliff Landslide Management Strategy Action Example 1) Engineering measures (coastal Construction of the Castlehaven protection works and drainage etc.) coastal protection and land drainage scheme 2) Public education and information Opening of Coastal Visitors’ Centre in 1998

3) The control of water in the ground Advice to homeowners leaflets (periodically updated & reissued)

4) Avoidance of seriously affected E.g. The Graben, Newport Road, areas Upper Ventnor

5) Further monitoring and research Ongoing ground movement monitoring, European funded projects, etc. 1) Engineering Measures

Castlehaven 2) Public education & information The Coastal Visitors Centre, Ventnor

www.coastalwight.gov.uk

• The Coastal Centre is open to the public daily providing displays and information about the coastline of the Isle of Wight, including geology, environment, archaeology, coastal defences and landslides. • The Centre also runs a varied programme of coastal based education. 3) Control of water in the ground: Advice to homeowners… (New leaflet issued October 2004) 4) Avoidance of seriously affected areas…

The Graben, Newport Road, Upper Ventnor 5) Geotechnical Monitoring… TheThe MonitoringMonitoring NetworkNetwork

•Consists of approximately 100 sensors. •Network constantly being expanded. •Includes inclinometers, tiltmeters, piezometers, extensometers and settlement cells, as well as numerous telltales and other low-tech monitoring points. •Readings taken at a variety of periods ranging from once a month to every three minutes. Coastal Defence Policy

IW Shoreline 5 Yearly Review Management Plan 100 Year Timeframe

Isle of Wight North East Coastal Defence Strategy Study and Undercliff Coastal Defence Strategy Study West Wight Coastal Defence Strategy Study

Implementation Plan Landslide Management Strategies Applicable to Climate Change (from Lee and Jones, 2004) • The use of no regret or low regret options • Adaptive management • Delaying action • Delay and buy time • Changing the land use / site abandonment • Contingency planning • Making allowance for climate change in engineering schemes Completed Revetment Siphon Drain ®®® Solution: Layout

Compressor Chamber

Electro- pneumatic drain - Line D Siphon drain Siphon Line C Siphon drain drain Line B Line A

Siphon drain Siphon Line G drain Line E Siphon drain Line F

Siphon drain Line H DRAINAGE CONNECTIONS

Outfall at Castlehaven Headland Networks & Groups

Local & Regional: • Standing Conference on Problems Associated with the Coastline (SCOPAC) • Forum • Isle of Wight Estuary Partnerships • Schemes of Management for European Marine Sites • South-East Climate Change Partnership

National: • Local Government Association Coastal Special Interest Group (LGASIG) • Chairmen of the Coastal Groups of and Wales • Technical Advisory Group (TAG)

Trans -National: • Arc Manche • Conference of Peripheral Maritime Regions of Europe (CPMR) and the Islands Commission of CPMR • World Landslide Networks e.g. United Nations International Strategy for Disaster Reduction (UN ISDR) Coastal Change, Climate PROTECT – and Instability (1997-2000) PRediction A Life Environment Of The ‘Success Story’ Erosion of Cliffed Terrains (2001-2004)

Response – Responding to the Risks from Climate Change (2003-2006)

EcoEnhance Eurosion (1999-2001) (2002-2004) supported by the European Commission's RESPONSERESPONSE LIFE Environment Programme Responding to the risks from climate change

– Developing sustainable strategies for the management of natural hazards in coastal areas taking account of the impacts of climate change.

www.coastalwight.gov.uk/response.html • 2003 – 2006 (3 years) • 5 Coastal Study Areas • 9 Project Partners