MA 19 Marazion to Longrock O p e n Location Reference: Marazion to Longrock Management Area Reference: MA19 Policy Development Zone: PDZ8 21 September 2016 APPENDIX WATPB4338R001D01 MA19 O p e n DELIVERY OF THE PLAN SUMMARY OF SPECIFIC POLICIES Policy Unit SMP1 SMP2 Policy Plan Policy 50 yrs. 2025 2055 2105 Comment Undefended Cliffs (including Do Important sediment source to intertidal area. NAI 19.1 NAI NAI NAI southern part of nothing meets AONB objectives. Mount) Hold the Marazion east Need to provide transition from NAI of cliffs to the 19.2 line / do NAI NAI NAI (Venton Cove) east into to HTL at Marazion Town frontage. nothing Potential heritage losses & economic impact on Hold the local economy under other policies unacceptable. 19.3 Marazion Town HTL HTL HTL line Defences at eastern end may require some extension to prevent outflanking. Accept reducing tidal window of exposure for St Michael’s 19.4 Hold the causeway and gradual reduction in use. HTL in first Mount - HTL NAI NAI (a) line epoch to allow for current maintenance programme Causeway completion. Maintenance of western harbour arm and protection of harbour area as remaining access route to and 19.4 St Michael’s Hold the HTL HTL HTL from Mount. Chapel Rock would need review by (b) Mount – Harbour line mid-epoch 2 as departure and landing stage link to the Mount’s harbour. A hold the line approach is required within this area Marazion west Hold the to provide a transition area between Marazion town 19.5 (Chapel Rock to HTL HTL HTL line frontage and Marazion Marsh which maintains the Marazion Bridge) defensive line. In order to adhere to legislation and maintain the integrity of this internationally important freshwater Hold the wetland site, a hold the line policy is preferred 19.6 Marazion Marsh HTL HTL HTL line through all three epochs. A more detailed strategy is required to consider the options for this area in more detail at the earliest opportunity. Key: HTL - Hold the Line, A - Advance the Line, NAI – No Active Intervention MR – Managed Realignment PREFERRED POLICY TO IMPLEMENT PLAN: From present day NAI along undefended cliffs. NAI for Marazion east. HTL along Marazion town frontage. (0-20 years) HTL (continued use/maintenance) for St Michael’s Mount causeway. HTL at St Michael’s Mount Harbour. HTL from Chapel Rock to Marazion Bridge. HTL along Marazion Marsh frontage. Medium term NAI along undefended cliffs. NAI for Marazion east. HTL along Marazion town frontage. NAI (20-50 years) (continued use) for St Michael’s Mount causeway. HTL at St Michael’s Mount Harbour. MR from Chapel Rock to Marazion Bridge. HTL along Marazion Marsh frontage. Long term NAI along undefended cliffs. NAI for Marazion east. HTL along Marazion town frontage. NAI (50 -100 years) (continued use) for St Michael’s Mount causeway. HTL at St Michael’s Mount Harbour. MR from Chapel Rock to Marazion Bridge. HTL along Marazion Marsh frontage. SUMMARY OF ISSUES AND PROGRESS INTENT OF THE CHANGE: The SMP2 recognised the intent to sustain the core areas of Marazion and the harbour area of St Michael’s Mount. Associated with this, the SMP2 recognised the importance of Marazion Marsh and the need to maintain the integrity of the internationally important freshwater wetland site. As identified in the SMP2, this poses significant issues in terms of the transition between these frontages and adjacent frontages. While the SMP2 defines specific transitional zones (policy units), it recognises that these 21 September 2016 APPENDIX WATPB4338R001D01 MA19 O p e n cannot sensibly defined by hard boundaries and that there is the need to consider these in an adaptive manner. To the east of Marazion, while around much of Goldsithney Bay the intent is to allow the cliffs to erode, the SMP2 Critical recognises that there are Sewer specific issues associated with the western section of this bay Existing Predicted where the existing defences to Defence Erosion Curve Marazion finish and where there is risk to properties, the sewerage system and potentially the road behind. Figure 1 The SMP2 identifies the need to consider this area in more detail. This is shown in Figure 1. Earlier studies highlighted that, with sea level rise, use of the causeway linking St Michael’s Mount would become more limited, gradually becoming unusable. The intent long-term is to abandon the use of the causeway. To the west of Marazion, the policy within the SMP is for Hold the Line. However, the SMP states that there will be the need for adaptation linked to management of the frontages to the west. Critically, Hold the Line reflects the important features to the western end of Marazion, rather than specifically the defence line. IMPLICATIONS: The underpinning intent is to maintain Marazion and the harbour area of St Michael’s Mount. However, in managing this there are potentially significant issues involving both hard assets such as property, roads and infrastructure, alongside the use of the area. The timescale for managing change ranges from relatively immediately actions (in relation to the eastern end of Marazion) through to longer term issues relating the causeway and the western frontage. Management of the transitional frontages have a significant influence on the future function and integrity of the town and access to St Michael’s Mount. This will also influence the tourism attraction of the area. Although, to a degree the direct issues relating to specific frontages (and causeway) may be addressed separately, there are broader scale issues that need to be considered over the area as a whole. PROGRESS REVIEW Both the broader issues and the specific problems have been examined in further detail within the Mounts Bay Strategic Assessment of Adaptive Frontages report (2015). This study examines the transitional sections of the frontage, primarily from the perspective of risk management. However, in examining this, the study considers what further actions will be required both in terms of risk management and in terms of communication and engaging organisations in making decisions relating to the area. 21 September 2016 APPENDIX WATPB4338R001D01 MA19 O p e n The following conclusions from the Mounts Bay Strategic Assessment of Adaptive Frontages report are highlighted: Marazion East (policy unit 19.2) In terms of the immediate drive for management, the sewer could be lost within the next 10 years, possibly sooner subject to specific storm conditions. Abandoning or rerouting the specific length of sewer, however, still does not resolve the longer term issues in terms of loss of properties, loss of other sections of the sewerage system, nor the risk to the road. Linked to this, is the issue of access to the town. The study indicates that there is a risk to the road, possibly over the next 50 years. Assessing the importance and impact of this highlights the link to management of the larger area, particularly the management of access across the Marazion Marsh area to the west of the Town. Based on the local assessment of damages, the scheme benefit to cost ratio is relatively low at 0.11 to 1, owing to the small number of properties that are affected by erosion at the frontage. In practice, this means that no Grant in Aid funding would be available, so the full amount of money would have to be provided by local funding. Potential beneficiaries in the area, such as: South West Water, local residents and businesses, would be required to provide a contribution in order for the scheme to be economically viable. Potentially there may be additional benefits linked to the management of defences across the Hold the Line frontage to the main town area. At least part of works cost might be set against the need to secure the end of the existing defences. Causeway (policy unit 19.4a) While not specifically examined in the above study, the study does highlight that losing the tidal access to St Michael’s Mount will influence tourism and tourist facilities with Marazion. This may have impacts on the use of the car park to the west of Marazion. It would also influence the approach to management of the Marazion Harbour. In addition, and depending on the approach in management to the west, the causeway may act as a means of retaining sediment to the west. This needs to be considered as part of long term management decisions. Western Marazion (policy units 19.5 and 19.6) This frontage is intrinsically linked to management of the frontages to the west (policy units 20.1, 20.2 and 20.3). Locally, however, the study has identified that over the longer term (50 years), there will be increased pressure on this frontage and increased risk of local flooding, potentially affecting the car park and the road. This needs to be discussed with the local community and land owners, while also considering the manner in which the coast to the west might be managed. As identified above, with road access to Marazion potentially being affected by decisions relating to Marazion East, there is a need to review future transport management over the broader area. General Issues. (Management Area 19) As may be appreciated from the above, there are several factors that influence the future of Marazion, including the important tourism industry and access to the town. These issues need to be considered as part of long term planning for the area. 21 September 2016 APPENDIX WATPB4338R001D01 MA19 O p e n ACTIONS: No. Type Owner Action Partners Programme 19/MON1/ Monitoring PCO Ensure that adequate baseline information is in place to allow on- CCc, EA 2016 On going PCO going long term monitoring of erosion and beach behaviour.