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Until relatively recently, coastal defences were constructed on an ad-hoc basis over relatively short lengths of coastline. They did not consider the impact on existing properties, coastal processes or the environment, and often caused erosion and flooding problems down drift. Increasing pressures on the coastal zone for more housing, marine trade and industry, and the demand for coast-based recreational activities also affects and influences existing and future coastal defence requirements.
Coastal management encompasses all the activities and multiple users that occur in and around the coast, and requires an integrated multi-disciplinary approach to provide an holistic approach to coast protection and flood defence. Coastal management aims to:
The non-statutory strategic management framework for coast protection, set out by Defra, requires the development of Shoreline Management Plans (SMP), and subsequently Coastal Defence Strategies (CDS). Economic, environmental and technical assessments are required to demonstrate the viability of any proposed scheme. There are three tiers of management for the coast.
Public consultation in the development of coastal plans is an important element of strategic management of the coast. Improving the communication and integration within and between operating authorities and other interested groups, raises awareness of the issues and the framework the operating authorities are working within. This will hopefully, in the long-term, result in society's acceptance of a more adaptive management approach.
Within the Solent area, the key authorities and agencies have a long history of working together and have forged strong and effective relationships when dealing with a number of issues, including coastal defence management.
A Shoreline Management Plan is non-statutory strategic policy document that provides a broad assessment of the long-term risks associated with coastal processes. It takes account of existing planning initiatives and legislative requirements and uses the best present knowledge on the possible effects of climate change and sea level rise. The plan informs, and is supported by, the statutory planning process. An SMP considers the objectives, policies and management requirements for 3 epochs;
The aims of an SMP are to identify and recommend technically, economically and environmentally sustainable policies for management of the shoreline in order to balance the management of coastal flooding and erosion risks, with natural processes, and the consequences of climate change.
The objectives of an SMP are to:
Details of the Solent's SMPs can be viewed in our Plans and Strategies page.
Coastal Defence Strategies (CDS) are the instrument for detailed implementation of SMP policies. This ensures that coastal erosion and tidal flooding problems are dealt with in a strategic manner, rather than on a parochial local basis. They include detailed assessment of economics, a range of technical solutions and also environmental assessments of the management options. The output is a prioritised programme of works and management programmes, including preferred engineering options.
Coast protection schemes are specific capital projects that arise from CDS studies; they typically include a phased programme of works, maintenance and monitoring. Any coastal protection and flood defence scheme must be technically and economically sound and sustainable , and environmentally acceptable and conform to the relevant licences and procedures if it is to gain permission and government grant aid funding.
When considering what is the most effective way of managing the coastline a range of options must be considered. In strategic terms there are four management policy options that may be assigned to each specified length of shoreline.
| Policy | Comment |
| Hold the line | Maintain or upgrade level of protection provided by defences |
| Advance the line | Build new defences seaward of existing defences |
| Managed realignment | To control or limit retreat of shoreline through management - this may involve removing or not maintaining some defences to allow the coastline to find its natural realignment, or to create important habitats |
| No active intervention | Not to invest in providing or maintaining defences |
Wherever decisions are made to hold the existing defence line it is likely that, due to current legislative and funding arrangements, and future climate change, it may be technically more difficult and increasingly expensive to protect, or continue to defend land or property from tidal flooding or erosion.
The means of achieving these policies will be identified and progressed through the development of a Coastal Defence Strategy.
Long-term monitoring of coastal processes has increased our understanding of how coastal systems function in conjunction with how defences interact with natural processes. It is now recognised that the coast is extremely dynamic and continually evolving.
Coastal monitoring is therefore vital in designing appropriate and cost-effective coastal and flood defences, improving understanding of climate change and its implications, and the interactions between the human and natural environments, and the implications of removing defences and creating key habitats.
Regional Coastal Monitoring Programmes comprise field-based, remote sensing, and environmental surveys to provide detailed digital baseline mapping of marine and terrestrial environments. Techniques include collection and analysis of topographic and bathymetric data, hydrodynamic data, vegetation mapping, and sediment types and budgets. The surveys produce freely available datasets which will aid better engineering designs, and improve our understanding of climate change factors and coastal processes. Over time this information will be an increasingly important resource for future research and management. The information and analysis will be an important element in strategic planning and operational management and enable the performance of existing schemes to be evaluated. For further details please visit the Channel Coastal Observatory's website www.channelcoast.org.
The Forum would like to thank Andy Colenutt of New Forest District Council for his assistance in preparing the text for this page.