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III. Evaluation of methods and strategies used for river and coastal management. Its function to protected the coastal areas is weakened. The energy reflected by a sea wall may pick up sediments, which scour and undermine the sea wall. 3.1 Effectiveness of the strategy.
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III. Evaluation of methods and strategies used for river and coastal management Its function to protected the coastal areas is weakened. The energy reflected by a sea wall may pick up sediments, which scour and undermine the sea wall. 3.1 Effectiveness of the strategy Some of the strategies taken are not as effective as expected.
Rusted groynes 3.2 Durability of the strategy Some of the strategies are not long-lasting and cannot withstand strong ocean waves.
Groyne construction requires relatively less construction cost. 3.3 What costs should be considered? 1. Economic costs a. Construction costs Most hard engineering incur construction costs which poor countries may not be able to afford. Construction of large-scale dam and reservoirs is a costly and lengthy process which incurs huge cost.
b. Maintenance costs All strategies have a limited lifespan and require regular maintenance work. Wooden groynes are cheap to build but have a short lifespan that requires constant repair after installation.
2. Ecological costs Some of the strategies, especially those related to hard engineering strategies such as building sea walls and dykes, may destroy the natural beauty along the coastline or river.
3. Social costs • Constructing reservoirs or managing retreat strategies along hazardous coasts requires displacing local residents and economic activities. • Compensation and relocation are costly and may cause social unrest. New buildings are built along the Chang Jiang
3.4 What benefits can we achieve? 1. Economic benefits • Human lives and properties are protected from floods and erosion by effective management strategies. • Values of properties and the cost of insurance can be maintained.
2. Ecological benefits Some areas with high ecological value can be protected from erosion and flooding through different river and coastal management strategies. Plants and animals living along rivers and the coast can continue to flourish and their habitats can be preserved.
Management strategies are intended to strike a balance between resource protection and economic development, therefore balancing and settling disputes among different interest groups. 3. Social benefits Coastal and river management can effectively prevent disasters. This can help promoting social harmony.
Nam Sang Wai 3.5 Which problems may be encountered after all the costs and benefits have been analysed? 1. Enforcement issue There are often criticisms about the inadequacy of existing strategies for conserving ecologically important sites under private ownership. It is evident that conservation of important habitats involving private lands cannot succeed without the support and cooperation of the landowners and other local stakeholder.
Victoria Harbour Protection Campaign 2. Divided opinions Different people may have different views on what should constitute an ecologically important site. Such conflicting opinions may hinder management of the debated area.