2B.11 Coastal Management

Question 1

2B.11a Hard engineering

general

Answer 1

Hard engineering is

The aim is to directly stop physical processes altogether (such as erosion or mass movement) or alter them to protect the coast (such as encouraging deposition to build larger beaches)

Question 2

2B.11a Hard engineering

advantages of hard engineering

Answer 2

It responds to the demand for action from stakeholders

It can protect the most vulnerable coastlines and completely eliminate the threat

Question 3

2B.11a Hard engineering

disadvantages of soft engineering

Answer 3

extremely expensive and ongoing maintenance costs

coastlines are made visually unattractive

the needs of the ecosystem are usually overlooked

defences built in one place frequently have adverse consequences further along the coast (promontory effect)

Question 4

2B.11a Hard engineering

Groynes

Answer 4

vertical stone or timber ‘fences’ built perpendicular to the coast and spaced along the beach

purpose:
prevents longshore movement of sediment and encourage deposition, building a wider higher, beach

impact:
deposition and beach accretion
prevention of longshore drift, sediment starvation and increased erosion downdraft

cost:
£150-250 per metre

Question 5

2B.11a Hard engineering

Sea Wall

Answer 5

concrete with steel reinforcement and deep-piled foundations; can have a stepped and/or ‘bullnose’ profile, to dissipate wave energy

purpose:
a physical barrier against erosion
they often also act as flood barriers
modern sea walls are designed to dissipate, not reflect, wave energy

impact:
destruction of the natural cliff face and foreshore environment
if reflective, it can reduce beach volume

cost:
£3000-10,000

Question 6

2B.11a Hard engineering

Rip Rap (rock armour)

Answer 6

large igneous or metamorphic rock boulders, weighing several tonnes

purpose:
their purpose is to break up and dissipate wave energy
often used at the base of the sea walls to protect them from undercutting and scour

impact:
reduced wave energy
sediment deposition between rocks
may become vegetated over time

cost:
£13,000-6000

Question 7

2B.11a Hard engineering

Revetments

Answer 7

stone, timber or interlocking concrete sloping structures which are permeable

purpose:
to absorb wave energy and reduce swash distance by encouraging infiltration
reduce erosion on dune faces and mud banks

impact:
reduced wave power
can encourage deposition and may become vegetated

Question 8

2B.11a Hard engineering

Offshore Rock Breakwater

Answer 8

large igneous or metamorphic rock boulders weighing several tonnes (offshore rip-rap)

purpose:
forces waves to break offshore, rather than at the coast, reducing wave energy and erosive force

impact:
deposition encouraged between breakwater and beach
can interfere with longshore drift

Question 9

2B.11b Soft engineering

Answer 9

a

Question 10

2B.11b Soft engineering

general

Answer 10

attempts to work with natural physical systems and processes to reduce the coastal erosion and flood threat

Question 11

2B.11b Soft engineering

advantages of soft engineering

Answer 11

less obvious and intrusive at the coast

Question 12

2B.11b Soft engineering

disadvantages of soft engineering

Answer 12

not suitable for all coasts

Question 13

2B.11b Soft engineering

beach nourishment

Answer 13

artificial replenishment of beach sediment to replace sediment lost by erosion, enlarge the beach, dissipate wave energy and reduce erosion, increase the amenity value of the beach

£20 million per km of beach

ongoing costs are high

sediment must not be sourced from elsewhere in the sediment cell

Question 14

2B.11b Soft engineering

cliff regrading and drainage

Answer 14

cliff slope angles reduced to increase the stability

re-vegetated to reduce surface erosion

in-cliff drainage reduces pore-water pressure and mass movement risk

costs £1 million per 100m

can be disruptive during construction

Question 15

2B.11b Soft engineering

dune stabilisation

Answer 15

fences are used to reduce wind speeds across the dunes
dunes are then replanted with marram and lyme grass to stabilise the surface, reducing wind and water erosion

fencing costs $400-2000 per 100m and replanting £1000 per 100m

can be very cost effective in the long term

Question 16

2B.11b Soft engineering

Answer 16

a

Question 17

2B.11c Sustainable Coastal Management

Answer 17

sustainable coastal management- managing the wider coastal zone in terms of people and their livelihood, social and cultural well-being, safety from coastal hazards as well as minimising the environmental impacts

Question 18

2B.11c Sustainable Coastal Management

methods

Answer 18

managing natural resources (fish, farmland, water supply) to ensure long-term productivity

managing flood and erosion risk where possible, or relocating to safe areas

creating alternative livelihoods before existing ones are lost to the sea

adapting to sea level rise by relocating, alternative building methods and water supplies

educating communities to understand why change is needed and how to adapt

monitoring coastal change and adapting to unexpected trends

Question 19

2B.11c Sustainable Coastal Management

causes of conflict

Answer 19

coastal natural resources may have to be used less in order to protect them- so people lose income

relocation may be needed where engineering solutions are costly or not technically feasible

some erosion and/or flooding will always occur, as engineering schemes cannot protect against all threats

future trends, such as sea level rise, may change, creating uncertainty and the need to change plan

Question 20

2B.11c Sustainable Coastal Management

Integrated Coastal Zone Management (ICZM)

Answer 20

The idea of ICZM was introduced at the 1992 Earth Summit meeting and aims to bring together economic decision-makers such as tourism, fishing and ports, and different government levels (including international). other aims include the conservation of coastal ecosystems, ensuring the ability of future generations to use the coast and the involvement of all relevant stakeholders

ICZM emphasises cooperation between all stakeholders so that everyone benefits. It is a dynamic process because of changing demands at the coast, and decisions are likely to be increasingly concerned with vulnerability and sustainability.

The EU adopted the Recommendation on ICZM in 2002, and Maritime Strategy Framework Directive of 2008 also emphasised a comprehensive and integrated approach to protect all European coasts and seas. ICZMs can now be found worldwide, at varying states of sophistication and with various levels of action