Coastal
Landscapes
and Change
Enquiry Question 4: How can coastlines be managed to meet
the needs of all players?
,2B.10 Increasing risks of coastal recession and coastal flooding have serious consequences
for affected communities.
The risks of coastal recession and coastal flooding look set to increase in the near future.
These will clearly affect coastal communities. The cost of both changes fall into three broad
categories:
Economic Costs - these include the loss of property in the form of homes and
businesses, the loss of transport lines, as well as the loss of farmland and other
means of livelihood.
Social Costs - these include the impacts on people, such as the costs of relocation
and community disruption, as well as the impacts on health and well-being, levels of
stress and hardship.
Environmental Costs - the loss of coastal habitats and ecosystems.
The higher the population density and the greater the concentration of economic wealth,
the greater the consequence and the higher the losses involved.
While in many parts of the world, rising sea levels will be managed by building higher flood
walls and stronger sea defences; there will be locations where the situation becomes
unmanageable. Most at risk are islands such as the Maldives, Tuvalu and Barbados. Here,
land will simply have to be abandoned and left to disappear beneath the sea, creating a
growing number of environmental refugees. The major issue will be one of deciding where
they should go to start a new life.
The Maldives
Rises only 2.4m (8 feet) above sea level at its highest point.
Sea level may sink all 1,200 islands of the Maldives.
Loss of tourism (25% of the economy).
Erosion of soft coral sands = loss of hotels/beaches.
Loss of fishing industry due to coral bleaching, water is too warm/deep = decline in
fish (fishing is the nation's second-largest industry).
Loss of reefs = loss of natural protection/barriers against erosion (1km of reef = cost
$1.25 million over 25 years).
Tuvalu
Group of islands in the Pacific Ocean.
Population of 12,000.
Highest point is 5m above sea level.
Sea level rise is 1.5mm per year (15cm a century).
Increase of coastal erosion - widest point is 400m.
, Food security = salty sea water = salty soils = can't grow crops = impact on the Pulaka
crop.
Salt water incursions into groundwater from porous coral.
Increased El Niño events = more drought
Unfair on them as they experience a severe impact but do not cause the problem.
2B.11 There are different approaches to managing the risks associated with coastal
recession and flooding.
Coastal Management - Different Approaches
There are four broad options available to describe makers:
Do nothing - let existing defences collapse
Advance the line - build coastal defences further out to sea, eg: artificial breakwaters
Hold the line - keep the coastline where it is by using hard engineering
Retreat - allow the coast to erode back to a defined line
Hard engineering is making use of concrete, stone and steel to provide the required
protection for the coast.
Soft engineering aims to work with natural processes to reduce the threats of coastal
erosion and flooding.
Hard
Strategy or Purpose Strengths Weaknesses
Soft
1. Costly (£3,000 -
Physical barrier made of
£10,000 per m).
reinforced concrete that 1. Effective.
Sea Wall Hard 2. Unsightly.
reflects wave energy and 2. Durable.
3. Reduces beach
prevents undercutting.
access.
Rip-Rap Hard Huge rock boulders piled up at 1. Effective. 1. Costly (£1,300 -
the base of a sea wall that 2. Durable. £6,000 per m).
Landscapes
and Change
Enquiry Question 4: How can coastlines be managed to meet
the needs of all players?
,2B.10 Increasing risks of coastal recession and coastal flooding have serious consequences
for affected communities.
The risks of coastal recession and coastal flooding look set to increase in the near future.
These will clearly affect coastal communities. The cost of both changes fall into three broad
categories:
Economic Costs - these include the loss of property in the form of homes and
businesses, the loss of transport lines, as well as the loss of farmland and other
means of livelihood.
Social Costs - these include the impacts on people, such as the costs of relocation
and community disruption, as well as the impacts on health and well-being, levels of
stress and hardship.
Environmental Costs - the loss of coastal habitats and ecosystems.
The higher the population density and the greater the concentration of economic wealth,
the greater the consequence and the higher the losses involved.
While in many parts of the world, rising sea levels will be managed by building higher flood
walls and stronger sea defences; there will be locations where the situation becomes
unmanageable. Most at risk are islands such as the Maldives, Tuvalu and Barbados. Here,
land will simply have to be abandoned and left to disappear beneath the sea, creating a
growing number of environmental refugees. The major issue will be one of deciding where
they should go to start a new life.
The Maldives
Rises only 2.4m (8 feet) above sea level at its highest point.
Sea level may sink all 1,200 islands of the Maldives.
Loss of tourism (25% of the economy).
Erosion of soft coral sands = loss of hotels/beaches.
Loss of fishing industry due to coral bleaching, water is too warm/deep = decline in
fish (fishing is the nation's second-largest industry).
Loss of reefs = loss of natural protection/barriers against erosion (1km of reef = cost
$1.25 million over 25 years).
Tuvalu
Group of islands in the Pacific Ocean.
Population of 12,000.
Highest point is 5m above sea level.
Sea level rise is 1.5mm per year (15cm a century).
Increase of coastal erosion - widest point is 400m.
, Food security = salty sea water = salty soils = can't grow crops = impact on the Pulaka
crop.
Salt water incursions into groundwater from porous coral.
Increased El Niño events = more drought
Unfair on them as they experience a severe impact but do not cause the problem.
2B.11 There are different approaches to managing the risks associated with coastal
recession and flooding.
Coastal Management - Different Approaches
There are four broad options available to describe makers:
Do nothing - let existing defences collapse
Advance the line - build coastal defences further out to sea, eg: artificial breakwaters
Hold the line - keep the coastline where it is by using hard engineering
Retreat - allow the coast to erode back to a defined line
Hard engineering is making use of concrete, stone and steel to provide the required
protection for the coast.
Soft engineering aims to work with natural processes to reduce the threats of coastal
erosion and flooding.
Hard
Strategy or Purpose Strengths Weaknesses
Soft
1. Costly (£3,000 -
Physical barrier made of
£10,000 per m).
reinforced concrete that 1. Effective.
Sea Wall Hard 2. Unsightly.
reflects wave energy and 2. Durable.
3. Reduces beach
prevents undercutting.
access.
Rip-Rap Hard Huge rock boulders piled up at 1. Effective. 1. Costly (£1,300 -
the base of a sea wall that 2. Durable. £6,000 per m).
