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Item which the Chairman has decided is urgent by reason of the need to avoid undue delay in advising Committee about this matter

 

Agenda Item No. 6

 

The Vale of Glamorgan Council

 

Scrutiny Committee (Economy and Environment):  17 June, 2014

 

Report of the Director of Visible Services and Housing

 

Sand Loss and Coastal Monitoring, Vale of Glamorgan Coastline

 

Purpose of the Report

1.         To consider the issue of sand loss from beaches around the Vale coastline.

Recommendations

1.         That Members note the contents of this report.

2.         That a report be tabled annually to Cabinet, and then to this Scrutiny Committee, detailing the progress of coastal monitoring in the Vale.

Reasons for the Recommendations

1.         To keep Members apprised of the current situation regarding sand loss and coastal monitoring along the Vale coastline.

2.         To deliver the requirements for monitoring identified in both Shoreline Management Plans (SMP) and develop an improved understanding of beach levels to inform future management decisions.

Background                   

2.         This report is provided in response to a Request for Consideration of a Matter by Councillor Steffan Wiliam, the details of which are shown within the agenda.

3.         The coastal zone is a highly dynamic environment and beach levels vary in response to various forces imposed on them by wind, waves and currents.  The Vale coastline is subject to a very large tidal range, which has a strong influence on the wave action dependent on the state of the tide. The volume of sediment available to be mobilised and deposited by these forces is key to the presence of beaches, along with the interaction with both natural and man-made structures in the coastal zone.  The impacts of climate change, particularly sea level rise and increased storminess, and human intervention will all have a role in modifying the Vale's coastline in the future.  The Severn Estuary (SE) SMP, and Lavernock Point to St. Ann's Head (LPSAH) SMP contain a comprehensive review of how the Vale coast functions, including coastal processes, defence assessments and the impact of marine aggregate extraction.

4.         Much of the Vale's coastline is composed of steep cliffs which are slowly eroding.  Sand therefore plays a limited role in protecting against flooding and coast protection across the Vale.  At a few key locations, such as Whitmore Bay, this role is more important where the beach offers protection to the toe of man-made defences.  Unfortunately, there is limited information available on historic or contemporary volumes of sand contained within the Vale's beaches.

5.         The Vale of Glamorgan Tourism Strategy, adopted by Cabinet on 21st July 2010, recognises Barry Island seafront and Whitmore Bay as the main tourism destinations within the Vale.  The sandy beach is identified as one of the main attractions drawing tourists to these destinations.

6.         It is generally recognised that the global climate is changing, with implications for sea level and the storminess of the climate. Changes to global sea level (eustatic change) are influenced by climatic changes as temperature rise results in increased volume of water through thermal expansion and melting ice.  The South of England is currently undergoing changes to the land level (isostatic), the land rebounding from glacial cover over 10,000 years before present.  Alterations to relative sea level can have implications for shoreline management, especially in areas heavily populated with human settlements including hard structures that cannot easily be moved to suit the adjustments to relative sea level.  The anticipated changes have implications for the management of the future coastline, but there remains considerable uncertainty both within the science of future climate modelling and the impact on shoreline management

7.         Human intervention, in its many forms, has had a significant influence on how our coasts have changed over time. One such activity is the removal (or dredging) of sediments from the offshore zone, which has the potential to affect our shorelines, through either affecting the flow of tides and waves towards the coast or through the removal of sediment which may otherwise contribute to the natural development of beaches. For that reason, dredging around the coast of the UK is strictly controlled, with government control and licensing of marine aggregate dredging in Wales administered by the Welsh Government (WG).  Details of the active dredge zones for the South West, which includes the Bristol Channel and Severn Estuary, are attached in Appendix A.  It has recently been announced that dredging has ceased at Holm Sands (Areas 377, 379 and 381), the closest dredge site to the Vale coastline, effective from 1 April 2014.

8.         The LPSAH SMP notes that there is evidence of sediment transport links between offshore sandbanks within some parts of the Bristol Channel and the beaches of South Wales. The links are generally weak, however, and do not imply that dredging will inevitably have impacts on the beaches.  The SE SMP notes that "numerous studies have been undertaken to assess the possible effects of aggregate extraction on coastal processes, but to date no effects have been proven."

9.         The LPSAH SMP identifies that the preferred option of 'Hold The Line' over the short- to medium-term in Whitmore Bay will potentially result in beach narrowing as sea levels increase and the beach is constrained by hard defences.  In the long term, the SMP identifies managed realignment at Whitmore Bay may enable beach narrowing, as a result of sea level rise, to be reduced, to retain the important tourist amenity beach.

Relevant Issues and Options

10.      The Vale of Glamorgan Council is defined as a Coastal Erosion Risk Management Authority under the Coast Protection Act 1949, as amended by Schedule 2 of the Flood and Water Management Act 2010, and is under no obligation to construct defences to prevent coastal erosion but has permissive powers to do so if it is deemed necessary.

11.      The Vale of Glamorgan coastline, from Lavernock Point to the mouth of the River Ogmore, is covered by the LPSAH SMP, produced by the Swansea and Carmarthen Bay Coastal Engineering Group and which was adopted on 6th November 2012 (Minute No C1923).

12.      The Vale of Glamorgan coastline, from Lavernock Point to Penarth Head, is covered by the Severn Estuary SMP, produced by the Severn Estuary Coastal Group and which was adopted on 17th November 2010 (Minute No C1125).

13.      Both SMPs contain actions to put in place a monitoring programme of erosion rates and beach levels around the Vale coastline.

14.      Monitoring of coastal erosion is managed at three different scales in Wales.  At a national level the Welsh Coastal Monitoring Centre, co-ordinated by Gwynedd Council, is leading in the development of a programme of ongoing monitoring funded by Welsh Government.  At a regional scale the coastal groups co-ordinate the collection of data on behalf of the member local authorities, partially funded by Welsh Government.  At a local scale individual maritime local authorities will need to develop monitoring in key areas or on a scheme specific basis, aiding in the delivery of duties as a Risk Management Authority.

15.      The Welsh Coastal Monitoring Centre (WCMC) is currently developing a national programme for coastal monitoring, and the Vale is represented on the Project Team.  Welsh Government funding is currently allocated to the WCMC until March 2015.  A business case has been submitted to Welsh Government including a LiDAR (Light Detection and Ranging) flight of the entire coast which will capture a baseline survey of the current beach levels, again acting as a baseline against which to compare future changes in the coastline.

16.      The Swansea and Carmarthen Bay Coastal Engineering Group currently commissions Spring and Autumn profile surveys at 25 locations around the Vale coastline, including two profiles in Whitmore Bay.  Collection of profile data commenced in 1998.  A licence for SANDS (Shoreline and Nearshore Data System) has recently been purchased, enabling the Vale to carry out analysis of this dataset.

17.      The Vale's beaches range from cobble sized material through to sand.  Different monitoring techniques are available to suit the different beach morphologies and site specific monitoring will be required to establish the status and vulnerability of beaches to future change in key areas.  A technical report will be produced identifying these areas and the proposed monitoring regime.  This report will be developed in conjunction with the WCMC over the next 12 months.

18.      An appropriate coastal monitoring regime will be developed and implemented by the Vale of Glamorgan Council, in conjunction with the groups identified above, for the Vale coastline.

19.      Beach levels in Whitmore Bay dropped on the upper beach following the winter storms in January and February 2014.  Subsequently beach levels have recovered and are anticipated to recover further over the summer months.  As previously advised, the LPSAH SMP identifies the potential for beach narrowing at Whitmore Bay as a result of sea level rise, which could have an adverse effect on tourism in the area in the future.  Improved monitoring in this area will provide a basis for future management decisions, including the potential impact on tourism and the wider economy

20.      A terrestrial laser scan topographic survey of Whitmore and Jackson Bays was undertaken on behalf of the Vale of Glamorgan Council in April 2014 following the severe winter storms early in the year.  This survey will provide a baseline against which to assess the recovery of beach levels and improve our understanding of the sediment dynamics in this area.  The survey also captured data on the promenade structures and adjacent cliffs to inform the ongoing management of erosion and wave overtopping in this area.  This survey will be repeated annually, subject to suitable funding, to establish the long-term trends in sand volumes in this embayment.

21.      The Council will continue to work with all other relevant organisations, including Risk Management Authorities and Welsh Government, to deliver the actions identified in the SMPs and manage the risk of flooding and coastal erosion within the Vale.

Resource Implications (Financial and Employment)

22.      Beach profile monitoring will continue to be funded via the Vale's annual subscription fees to the Swansea and Carmarthen Bay Coastal Engineering Group

23.      The cost of providing additional beach level surveys will need to be met from existing budgets or funding provided by Welsh Government to deliver the Flood and Water Management Act 2010.

24.      The Welsh Coastal Monitoring Centre will co-ordinate future large-scale coastal monitoring nationally with funding provided by Welsh Government.

Sustainability and Climate Change Implications

25.      The proposed monitoring will provide a baseline against which to assess future Climate Change implications.

Legal Implications (to Include Human Rights Implications)

26.      There are no Legal or Human Rights Implications in respect of this report.

Crime and Disorder Implications

27.      There are no Crime and Disorder Implications in respect of this report.

Equal Opportunities Implications (to include Welsh Language issues)

28.      There are no Equal Opportunity Implications or Welsh Language Issues in respect of this report.

Corporate/Service Objectives

29.      To protect and enhance the Vale's natural and built environment.

30.      To ensure current and future generations of Vale residents and visitors enjoy the built and natural environment and actively protect and maintain them.

31.      To manage the effects of climate change on the built and natural environment.

Policy Framework and Budget

32.      This matter is within the Policy Framework and Budget.

Consultation (including Ward Member Consultation)

33.      The consultation process for the production of both the Severn Estuary Coastal Group, Severn Estuary SMP2 (from Lavernock Point to Anchor Head) and the Swansea and Carmarthen Bay Coastal Engineering Group Lavernock Point to St. Ann's Head SMP2 has been concluded.  Public meetings were held locally, these having been facilitated by the Consultants involved.  Local Members were advised of these meetings.  No further consultation has been undertaken.

Background Papers

The Severn Estuary Shoreline Management Plan http://www.severnestuary.net/secg/smpr.html

Lavernock Point and St. Ann's Head Shoreline Management Plan http://www.southwalescoast.org/content.asp?id=58

 

Contact Officer

Clive Moon, Principal Engineer (Flood and Coastal Risk Management)

Tel. No. 02920 673 277

 

Officers Consulted

Director of Development Services

Operational Manager, Legal Services

Accountant, Building and Visible Services

 

Responsible Officer:

Miles Punter, Director of Visible Services and Housing