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Here you will learn about the adaptation approaches that can be used to reduce the impacts expected from climate change by the 2050s on coastal erosion and coastal defence structures.
Fundamental in adaptation to the risks from coastal erosion associated with climate change is a decision about whether or not to intervene to reduce or stop the recession of the shoreline. In areas where there are extensive developments, or important economic assets, it will usually be likely that the most cost-effective solution is to provide coastal defences (and then subsequently maintain them to suitable standards), rather than relocate the assets. Where small or isolated assets are vulnerable, it would be more cost-effective, and more sustainable, to relocate the assets than it would be to provide coastal defences. This adaptation approach is particularly relevant where assets can be moved without loss of their overall function (i.e. landward relocation of mobile homes, and re-planning the layout of golf courses). Where it is not possible to do this, then local management that is sensitive to the nature of the region’s coastline is possible. Where this approach is selected, innovative options will increasingly be used in preference to traditional hard engineering approaches. Examples include the use of bio-degradable geotextile ‘sandbags’ to stabilise dune toes, instead of the more traditional cobble-filled wire mesh gabions. Along frontages where coastal defences are already in existence, their ongoing inspection and maintenance is critical. The more recently constructed defences will have been designed taking into consideration the effects of sea level rise in accordance with guidance from central government (Defra), but older defences are unlikely to have considered such matters and, due to their age, will also require significant upgrading and/or replacement before the 2050s. Pro-active identification of the need for this will be determined through the ongoing processes of Shoreline Management Plans and Coastal Defence Strategy Plans, which are subject to periodic review and updating in light of the latest climate change science and the nature and scale of the erosion risks posed.
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The principal adaptation approaches will depend on the assets that are being threatened by erosion. Where there is low grade agricultural land or public open space that is being lost, the erosion should be allowed to continue. This allows the coastal response to be more self-sustaining and the approach is more cost-effective. On a similar theme, where mobile assets are threatened on a local scale, they should be relocated in preference to being defended by new structures. Some local scale intervention will be inevitable, however, where assets are static, or where longer term planning needs to be undertaken before relocation. Where major assets are present, existing defences should be regularly inspected, maintained and, at the end of their design life, replaced or upgraded, taking into consideration the latest allowances for climate change in their design. Ongoing coastal monitoring by the Northumbrian Coastal Authorities Group remains important due to the dynamic nature of large parts of this coastline and the need to better quantify the effects of climate change on natural coastal processes.
Given that so much of the coastline is already defended, the main adaptation to climate change will be based around regular inspection and maintenance of existing structures and upgrade/replacement or landwards realignment when they come to the end of their design lives. In more natural areas, such as linked beach and dune systems, local and low-scale management intervention may be required to prevent breaching, but in the main the preference for undefended areas will be to allow natural landward migration where this does not compromise assets. Ongoing coastal monitoring by the Northumbrian and North East Coastal Authorities Groups remains important to understand the links between beach behaviour and defence performance, and how these are influenced by changing sea levels.
Where defences are already in existence, such as at Seaham north promenade, it will be necessary to modify or upgrade them to counter the increased pressure caused by sea level rise and wave activity. In the many areas within this frontage where no defences are present, this is generally because there is little development. The preferred approach would be to discourage new development from eroding coastal margins to avoid the need for later defence structures. In some areas, such as Noses Point, Hawthorne Hive and Shippersea Bay, local defences may be required to prevent ongoing problems from erosion. Ongoing coastal monitoring by the North East Coastal Authorities Group remains important in this sub-region to better quantify the effects of climate change on natural coastal processes.
Where defences are already in existence, such as at Hartlepool Town and Seaton Carew, it will be necessary to modify or upgrade them to counter the increased pressure caused by sea level rise and wave activity. Elsewhere, land use planning needs to proactively consider likely future recession rates of the coast under rising sea levels before releasing areas of land for development. In some areas, it will be necessary to pro-actively consider the relocation of assets such as the minerals railway line, parts of the Cleveland Way long-distance footpath and the Cowbar Lane road. Ongoing coastal monitoring by the North East Coastal Authorities Group remains important in this sub-region to better quantify the effects of climate change on natural coastal processes, especially in areas where landward relocation of assets or redevelopment of prime coastal sites is being considered.
For an overview of the adaptation for your local area please click on the list/map below.
Where possible, the natural landward migration of the dunes and beaches should be uninterrupted, allowing these features to be self-sustaining in the longer term. In places where this process threatens important assets, careful consideration of appropriate management responses is needed in advance of problems arising and local responses being implemented. Structural inspections of defences and monitoring of beach levels will be important because this will identify whether intervention is needed to maintain existing structures or natural features (e.g. beaches or dunes) to safeguard assets. Further monitoring of the natural dynamics, and how this will alter with climate change, will be particular important in Alnmouth Bay around the vicinity of the channel of the River Aln. Periodic dredging will be required in the River Coquet to remove the build-up of sediment in the river mouth. Alternative approaches, such as increasing the ebb-flow flushing of the river may also prove of some assistance in resolving the siltation problem. The Northumberland Shoreline Management Plan (SMP) 2 is being prepared throughout 2008. When finalised, this will have more information about the recommended management actions to counter the risks presented from coastal erosion under a changing climate. For further information about the Northumberland SMP 2 click here.
Where coastal assets are threatened by erosion, they will usually be localised problems that do not warrant a major structural intervention. Due to this, the response in many areas should be to relocate those assets which can be moved to avoid the need for defences that will require expensive and ongoing maintenance. For example, golf clubs and caravan parks should be identifying the potential threats from erosion now and planning to redesign courses or site layouts so that they can continue to function, rather than maintain a fixed course design or site layout and attempt to halt the recession. Structural inspections of defences and monitoring of beach levels will be important because this will identify whether intervention is needed to maintain existing structures or natural features (e.g. beaches or dunes) to safeguard assets. The Northumberland Shoreline Management Plan (SMP) 2 is being prepared throughout 2008. When finalised, this will have more information about the recommended management actions to counter the risks presented from coastal erosion under a changing climate. For further information about the Northumberland SMP 2 click here.
Local management intervention, through recycling of sand or re-location of the anti-tank blocks that help break up wave energy at the dunes toe will help manage the threat of breaching. Fencing and signage will help manage the dune erosion due to pedestrian trampling, whilst small-scale intervention using brushwood fencing will help trap sand and stabilise the dunes. Structural inspections of defences and monitoring of beach levels will be important because this will identify whether intervention is needed to maintain existing structures or natural features (e.g. beaches or dunes) to safeguard assets. The Northumberland Shoreline Management Plan (SMP) 2 is being prepared throughout 2008. When finalised, this will have more information about the recommended management actions to counter the risks presented from coastal erosion under a changing climate. For further information about the Northumberland SMP 2 click here.
The physical processes operating in Druridge Bay are not yet fully understood and therefore beach monitoring should continue. Over time, the landward migration of the beaches and dunes may prompt questions about local management intervention in the vicinity of car parks, but the preference should be to relocate these assets rather than protect around them. Large-scale management intervention should be avoided along this frontage as it is likely to adversely affect the physical functioning of the Bay. At present, there is some discussion regarding the potential for development of a tourist centre in Druridge Bay. If this progresses, it must take due account of the likely future changes in shoreline position and vulnerability under a changing climate. This information will be obtainable from the Northumberland Shoreline Management Plan (SMP) 2 at the end of 2008. The Northumberland Shoreline Management Plan (SMP) 2 is being prepared throughout 2008. When finalised, this will have more information about the recommended management actions to counter the risks presented from coastal erosion under a changing climate. For further information about the Northumberland SMP 2 click here.
Where defences are already in existence, such as at Seaham north promenade, it will be necessary to modify them to counter the increased pressure caused by sea level rise and wave activity. This could be in the form of rock revetments along the toe of existing structures to help break-up wave activity, or short rock groynes across the foreshores to help maintain beach levels. In the many areas within this frontage where no defences are present, this is generally because little development is present. In light of the predicted increase in shoreline recession rates due to climate change, a key part of adaptation should be to discourage development in areas close to the coastal margin that would pre-define the need for subsequent engineering intervention. The only notable exceptions to the above principle are at Noses Point and at Hawthorn Hive and Shippersea Bay. At Noses Point, increasing recession rates associated with climate change may necessitate some local defence if the waste in-fill that is being released by erosion is proven to be hazardous to the public or to the environment. At Hawthorne Hive and Shippersea Bay local protection to the railway line will ultimately be required. In the longer-term (i.e. beyond this study’s time horizon of the 2050s) it will be necessary to re-align the railway line. Further specific actions for Easington have been identified in the River Tyne to Flamborough Head Shoreline Management Plan 2. To view these click here.
Local-scale training of the outfall of Crimdon Beck, or local protection works to Hart Warren dunes will be required if erosion control is deemed necessary to assist in steering the natural development of the frontage under a rising sea level. Throughout the defended frontages, to counter the increasing risk of damage, breaching or overtopping due to sea level rise, there will be a need for continued inspection and maintenance of the existing defences, which are critical to key areas such as the Heugh, Victoria Harbour, Hartlepool Marina, Hartlepool town and Seaton Carew. Consideration will need to be given to upgrades of structures as they tend towards the end of their design lives. In presently undeveloped areas, such as part of Seaton Sands, or areas potentially prime for redevelopment, such as parts of North Sand, land use planning activities should give suitable considerations to projected future coastline evolution to avoid allowing development in areas that will become increasing susceptible to erosion or wave overtopping. This can be ensured through appropriate linkages between statutory Town and Country Planning and non-statutory sub-regional Shoreline Management Planning and national Coastal Erosion Risk Mapping. Further specific actions for Hartlepool have been identified in the River Tyne to Flamborough Head Shoreline Management Plan 2. To view these click here.
In undefended areas, the best form of adaptation to the cliff recession will be landward roll-back of assets, such as the golf course, rather than the construction of new defences. Given the heavily defended nature of the coastline, structural inspections of defences and monitoring of beach levels will be important because this will identify whether intervention is needed to maintain existing structures or natural features (e.g. beaches or dunes) to safeguard assets. Local dune management will be needed to counter both physical erosion from the sea and winds and the trampling erosion caused by pedestrian access from car parks to the beaches through the dunes. The Northumberland Shoreline Management Plan (SMP) 2 is being prepared throughout 2008. When finalised, this will have more information about the recommended management actions to counter the risks presented from coastal erosion under a changing climate. For further information about the Northumberland SMP 2 click here.
There will be a need to monitor the changes in beach and dune levels at the western end of Coatham Sands as the protection offered by the German Charlies reduces with rising sea levels. Contingent upon the results from this monitoring, intervention may be required at some point to prevent breaching through the dunes and sea flooding of the backing floodplain. At Coatham Sands, some local management of access routes through the dunes will be required as beach use is set to increases with rising temperatures. This will be needed to reduce the destabilisation of the dunes due to trampling and help safeguard its function of providing natural defence against sea flooding to Warrenby and Coatham. A coastal defence scheme will be required to limit sea water flooding of parts of Redcar due to overtopping of existing defences. The design of this scheme must anticipate climate changes in its design. Monitoring and maintenance of the performance of existing defences at Skinningrove is important to ensure adequate protection against future sea levels and storm events. Consideration needs to be made now to relocating the minerals rail line that runs along the contours of Warsett Hill and parts of the Cleveland Way footpath. Planning also needs to be undertaken now to relocate sections of Cowbar Lane away from the undefended eroding cliff edge. Monitoring also needs to be undertaken of the recession rates of the Cowbar Nab headline and the effectiveness of the cliff protection and stabilisation works fronting Cowbar Cottages. Further specific actions for Redcar & Cleveland have been identified in the River Tyne to Flamborough Head Shoreline Management Plan 2. To view these click here.
In the area of Littlehaven, the seawall should be repaired and regularly inspected in the short-term and in the longer-term it should be realigned to a more landward configuration: it is presently protruding seaward and intercepting the high water mark. Such realignment will not completely remove the need for ongoing inspection and maintenance, but it should ensure that the costs of these activities are minimised compared with attempting to maintain the present configuration in the face of rising sea levels. Structural reinforcement will be required along Herd Sands where the rising high water mark will intercept the promenade. Beyond the 2050s, some realignment might be a necessary adaptation, but this will not be needed before then along this frontage. At Trow Quarry a means of protecting the coastline against erosion is urgently required. Under rising sea level it will be necessary to monitor the performance of this scheme, with a view to amending the management approach if necessary, contingent upon the findings of the ongoing monitoring. At Old Harbour Quarry, some form of intervention will be required in the form of localised defences to counter the erosion through the caves at the base of the cliffs. This will prove effective up to the 2050s, but may require alternative approaches beyond that date and therefore management planning will need to consider the possibilities of waste removal before this time. Further specific actions for South Tyneside have been identified in the River Tyne to Flamborough Head Shoreline Management Plan 2. To view these click here.
Throughout the frontage, monitoring of coastal processes and coastal change and the inspection and maintenance of existing coastal defences is the key to continuing to deliver a sound coastal defence system, even in the light of future climate changes. Over forthcoming decades, the strengthening, raising or replacement of defences will be required, but the need for this can be identified and planned well in advance via the ongoing Shoreline Management Plan and Coastal Defence Strategy Plan processes. Whilst the removal or realignment of defences remains an option that should always be considered, the number and value of cliff-top assets protected by the existing defences means that their continued maintenance between now and the 2050s remains viable and feasible. Further specific actions for Sunderland have been identified in the River Tyne to Flamborough Head Shoreline Management Plan 2. To view these click here.
The major erosion risks along this frontage have been addressed through recent major coastal defence schemes. With rising sea levels, it is critically important to monitor the performance of these schemes. At Lynemouth, it may be necessary to further intervene to prevent outflanking of the existing revetment. This could be in the form of an extension of the defence along the shore. At Newbiggin Bay there will be the need for further intervention as the sand deposited during the initial capital scheme is progressively transported away. This will be in the form of periodic sand ‘top-up’ nourishments. In Cambois Bay the erosion will lead to pressure for defences to protect some assets. Consideration of appropriate management responses should be given well in advance of the problems becoming manifest so that suitable planning and action can be taken. In these considerations, options of both relocation of the assets and provision of defences should be evaluated. Monitoring should also consider the threats from sea cliff erosion, and how these may change with rising sea levels, at Newbiggin Caravan Park, Sandy Bay Caravan Park and within Cambois Bay. The Northumberland Shoreline Management Plan (SMP) 2 is being prepared throughout 2008. When finalised, this will have more information about the recommended management actions to counter the risks presented from coastal erosion under a changing climate. For further information about the Northumberland SMP 2 click here.
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