Flood Prevention and Mitigation
Flood control methods are used to reduce or prevent the detrimental effects of floodwaters. Flood relief methods are used to reduce the effects of floodwaters or high water levels. The flood mitigation involves the management and control of floodwater movement, such as redirecting flood run-off through the use of embankment/bands and flood gates, rather than trying to prevent floods altogether.
Depending on locality and the nature of the flooding, a number of structural and non-structural mitigation measures may be available. However, flood mitigation measures may only lessen the impact of flooding.
Structural flood mitigation is where physical structures are constructed or modified to reduce/prevent the impact of flooding on government and individual infrastructure.
Figure: Flood Prevention and Mitigation
Retrofitting of Building / Critical Infrastructure
Retrofitting defined as reinforcement or upgrading of existing structures to become more resistant and resilient to the damaging effects of hazards.
Retrofitting requires consideration of the design and function of the structure, the stresses that the structure may be subjected to from particular hazards or hazard scenarios and the practicality and costs of different retrofitting options. Examples of retrofitting include adding bracing to stiffen walls, reinforcing pillars, adding steel ties between walls and roofs, installing shutters on windows and improving the protection of important facilities and equipment.
Figure: Building Retrofitting
Community-Based Disaster Risk Reduction
A resilient community is one that can absorb disturbances, change, reorganize, and still retain the same basic structures and provide the same services. If communities are to be made disaster-resilient, it is crucial to “look at the many impacts of disasters and build the long-term capacity of communities to both adapt to and cope with uncertain risks”. The role that communities and local government can and should play in disaster risk reduction (DRR) is widely recognized, with community-based DRR (CBDRR) becoming a cornerstone of DRR programming, promoted through the Hyogo Framework for Action and the more recent Sendai Framework for Disaster Risk Reduction. Community Based Disaster Risk Management (CBDRM) is an approach of increasing the disaster resilience of a community by strengthening its local capacity. The successful use of a community-based disaster risk reduction approach is based on the combination of all capacities, including all strengths and resources available for reducing disaster risk or impact within a community, society or organization (UNISDR, 2006).
CBDRM is a process, which leads to a locally appropriate and locally ‘owned’ strategy for disaster preparedness and risk reduction. In CBDRM communities at risk are actively engaged to reduce their vulnerabilities and enhance their capacities through;
• Evaluation of disaster risks
Figure: A Typical CBDRM Process