Presentation on theme: "BackwardForwardHomeExit III. Evaluation of methods and strategies used for river and coastal management 3.1 Effectiveness of the strategy Some of the."— Presentation transcript:
BackwardForwardHomeExit III. Evaluation of methods and strategies used for river and coastal management 3.1 Effectiveness of the strategy Some of the strategies taken are not as effective as expected. The energy reflected by a sea wall may pick up sediments, which scour and undermine the sea wall. Its function to protected the coastal areas is weakened.
BackwardForwardHomeExit 3.2 Durability of the strategy Some of the strategies are not long-lasting and cannot withstand strong ocean waves. Rusted groynes
BackwardForwardHomeExit 3.3 What costs should be considered? 1. Economic costs Most hard engineering incur construction costs which poor countries may not be able to afford. a. Construction costs Construction of large- scale dam and reservoirs is a costly and lengthy process which incurs huge cost. Groyne construction requires relatively less construction cost.
BackwardForwardHomeExit All strategies have a limited lifespan and require regular maintenance work. b. Maintenance costs Wooden groynes are cheap to build but have a short lifespan that requires constant repair after installation.
BackwardForwardHomeExit 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.
BackwardForwardHomeExit 3. Social costs Constructing reservoirs or managing retreat strategies along hazardous coasts requires displacing local residents and economic activities. 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. Compensation and relocation are costly and may cause social unrest. New buildings are built along the Chang Jiang
BackwardForwardHomeExit 3.4 What benefits can we achieve? 1. Economic benefits Human lives and properties are protected from floods and erosion by effective management strategies. 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. Values of properties and the cost of insurance can be maintained.
BackwardForwardHomeExit 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.
BackwardForwardHomeExit 3. Social benefits Coastal and river management can effectively prevent disasters. This can help promoting social harmony. Management strategies are intended to strike a balance between resource protection and economic development, therefore balancing and settling disputes among different interest groups.
BackwardForwardHomeExit 3.5 Which problems may be encountered after all the costs and benefits have been analysed? There are often criticisms about the inadequacy of existing strategies for conserving ecologically important sites under private ownership. 1. Enforcement issue 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. Nam Sang Wai
BackwardForwardHomeExit Different people may have different views on what should constitute an ecologically important site. Such conflicting opinions may hinder management of the debated area. 2. Divided opinions Victoria Harbour Protection Campaign