EQ4: How can coastlines be managed to meet the needs of all players? GapFill

We build coastal defences to reduce coastal erosion rate and reduce the risk of coastal  weatheringbeachesfloodingwaves.  They create a barrier between the sea and the land.  They also dissipate and reflect wave energy, trap sediment and build up the height of the coastline, sometimes far higher than regular high tides.

Strong onshore winds, storms (low-pressure weather systems) and the shape of the coast can all work together to create storm  pressuressurgesspillstides – inundating coastal regions with seawater.

Traditional forms of coastal engineering have involved concrete, rock and wood –  cheapmodernsofthard engineering.  They’re said to work against nature, and can be damaging to the local environment, but they still form important parts of planning when we take a ‘hold the line’ approach.

 ExpensiveOld-fashionedHardSoft engineering works with nature, harnessing natural depositional processes to create valuable habitats such as dunes and marshes.  We can also include sustainable management and planning within this category.

 HardSingularModernTraditional management takes into account a wide variety of techniques – hard, soft and management, and actions across the wider coastal zone.  This is because actions on one part of the coast can have serious implications elsewhere.

In very important places we use hold the line to prevent the coast from being eroded or flooded.  We maintain existing coastal defences or build new ones, often using hard engineering.  Sometimes we want to  retreatholdremoveadvance the line.  This involves creating new defences out to sea; for example, creating new marshes.  One way to slowly give up the land to the sea is managed  retreatstabilisationadvancementswitching.  Land is slowly lost to the sea; for example, by not renewing sea defences and allowing the creation of marshes.  The simplest approach is called ‘do nothing’, or ‘no  activecontrolerosionpassive intervention’.  The rate of retreat is monitored, but low-value land is sacrificed and the sediment created helps protect areas of the coast downstream. 

In England and Wales there are  5051122 shoreline management plans (SMPs) shared between the 11 sediment cells. 

Each plan aims to manage the coast over a long time frame – up to 100 years – and sets out predicted erosion rates and flood risk for the coast.

On a large scale,  integratedholisticinterestingintegral coastal zone management (ICZM) was developed due to the complexity of the real world.  Many different people and organisations own land and use the coastal zone – both land and sea – for a variety of purposes such as fishing, tourism, wind farms, towns and ports.  Some of these land uses and stakeholders are likely to conflict with each other.  ICZM can be implemented on regional scales throughout the world.

In order to choose the best management policies for a stretch of coast, we must consider several factors:

•  AccountabilityVulnerabilityFeasibilityPossibility – whether it is technically possible to implement particular types of engineering in the area, and to determine which type is best – e.g. hard or soft engineering.  Is the proposed management likely to work?  Will there be unforeseen consequences?
•  CommercialGovernmentalEnvironmentalSocial sensitivity – are there any constraints on hard management that could damage ecosystems; for example, could it damage rare plants, protected species or habitats, protected areas, conservation sites or SSSIs (sites of special scientific interest)?
• Land  use-lessvalueprotection – how much is the land worth (this varies from country to country, and even within a country)?  Large cities and settlements, and important infrastructure and installations such as gas terminals, will be protected by hard management.  However, if the protection and maintenance costs are far greater than the value of the land, then defences are not likely to be built.  For example, a sea wall might cost as much as £10,000 per metre.
•  EnvironmentalEconomicPoliticalSocial – governments are often responsible for funding coastal management schemes.  It’s up to the governments how much they want to spend on coastal engineering.  In some countries, sudden changes in leadership can significantly influence the spending on coastal management.
•  PoliticalSocialStabilityEnvironmental – effects on people, e.g. well-being, relocation, sense of security, amenity value of the coast.