Coastal Management Methods

Managing the coast can be done in a number of ways and all have costs and benefits. Where hold the line and advance the line strategies are employed soft or hard engineering techniques can be use by authorities. Building defences is expensive to planners use cost-benefit analysis to decide where they should occur.

Hard Engineering - Major Construction

Large, expensive constructions are visually intrusive.

Description	Advantages	Disadvantages	Initial cost
Timber/rock structures built at 90° to the coast. Interrupt longshore drift by trapping sediment enlarging the beach between groynes. Wider beaches attract tourists & absorb more wave energy Backshore protected from erosion/flooding	The least expensive hard engineering strategy to build and maintain. A wider beach has amenity value for locals and the tourism industry.	Can be visually intrusive Terminal groyne syndrome	£25-20 per metre (E5000-10,000 per groynes often positioned at 200 metre intervals)
Stone/concrete wall built along the back of the beach/at the foot of a cliff. Sometimes vertical, but modern sea walls are typically curved (the side facing the sea is concave). Prevents erosion/flooding by absorbing & reflecting wave energy.	Often topped by a promenade that locals and tourists can walk along. Reflect the waves to protect cliffs and settlements from erosion and flooding.	Can be visually intrusive Can restrict beach access It is the most expensive defence to build and maintain. Reflected energy can affect other areas.	86000 per metre

Taller, cheaper, more natural—198 visually intrusive

Soft engineering - Environmentally better defences, not visually impairing.

Description	Advantages	Disadvantages	Initial cost
Sand/shingle is added to an existing beach, enlarging it. Wider, higher beach protects the backshore from wave erosion/flooding.	Relatively inexpensive to implement & maintain (the sediment used is typically dredged from a nearby offshore bar). Wider beach looks natural and has amenity value for locals and tourism.	Removal of sediment from a nearby offshore bar creates deeper water, allowing increased wave energy (less friction) to attack the coast. This disequilibrium may cause the replenished beach to erode quickly.	3000 per metre
Removal of rock to reduce the angle of the cliff, making it less steep. Cliff drainage involves installing pipes into the cliff allowing water to flow away. Both methods stabilise cliffs with soft lithologies (e.g., clay), reducing the risk of mass movement, e.g., slumping.	Relatively inexpensive to implement and maintain.	Regrading can involve retreating the cliff so land can be lost. Drained cliffs can dry out and become unstable, causing rockfall. Difficult to install. Can be costly.	Variable depends on local geology and size of cliffs.

 

Planning

• Planners need to find sustainable ways of managing the coast, minimising conflicts between human needs and the environment.
• Coastal management is expensive and needs to be worth the money. This implies the adoption of holistic coastal management. This means looking at the whole coastline instead of one area.
• This takes into account all users, protects important areas, and promotes sustainability.
• We refer to this process as Integrated Coastal Zone Management.

I.C.Z.M. - This takes into consideration:

1. The value of the land and buildings is justified by the cost.
2. Building defences may have an impact elsewhere.
3. What's best for the environment?
4. Long-term planning—climate change.
5. Economic costs and benefits—present/future.
6. Needs of different groups of people.
7. The sea and land environment.

• Policymakers must consider sustainable management as the coastline, which includes environmental, economic, and social factors and must be long-term.

SMPs

• The Environment Agency produces detailed Shoreline Management Plans (SMPs).
• This sets out which areas of the coast should be managed and how.
• It is important to note that doing nothing is still a management strategy. The aim is to stop issues like terminal groyne syndrome, where some zones of protection were causing areas down drift to be starved of sediment, which in turn increases erosion.

BEACHES

• As beaches are natural sea defences, the energy of the waves can be absorbed before it reaches the cliff.
• Coasts with rapid erosion, often have narrow beaches or no beach at all.
• The traditional way of solving this is by allowing the beach to grow, but they are expensive.
• Groynes allow the beach to grow by trapping sediment from longshore drift, but trapping sand in one place stops it from reaching another.
• Without a beach, cliff erosion is increased.

Naish Holiday Village

Naish holiday village suffers rapid erosion because groynes at Highcliffe further west have starved it of sand. Without a beach, the park's erosion has escalated, requiring the council to invest millions in protecting Barton.

STAKEHOLDERS	Their views on the costs and benefits of coastal protection.
Coastal residents/business owners in Christchurch, Milford, and Barton	To safeguard their homes, businesses, and tourist sites, they opt for a conservative approach. Most favour hard engineering, but it's expensive. Ugly sea defences can be an eyesore and can also deter visitors.
Local politicians/council	Need support of all local people; have to be careful not to favour 1 more than another; they want effective coalfield protection, not at any price.
Local people living inland	Unaffected by coastal erosion, but gear that taxes will need coastal protection; they prefer low-cost options. They don't want low value and to be protected.
Environmentalists	Fear habitats and sensitive ecosystems will be affected by the construction of sea defences; prefer to do nothing, says engineering.
Fisherman boat users	Their priority is access to the sea; they want harbours, marinas, and some beaches protected to maintain this.

NO PROTECTION—why...?

• Hard engineering methods will drive away tourists and negatively impact the economy.
• The cost is high and will be deducted from the residents' funds.
• Residents don't use the holiday park, so they don't care about it.
• It's not sustainable because it disrupts habitats and ecosystems.
• The park can be moved to another part of the coastline not experiencing rapid erosion.