Since human evolved on earth, urbanization was focused on two major objectivities: defense and resources harvesting. The major objective was always achieved in the wider sense i.e. defending the population from other humans and from natural disasters. This defensive approach was also applied to urban drainage taking as consequence the scare attention on the negative impact of urbanization on natural systems.
The emergence of environmental sustainability tried to mitigate negative impacts of urbanization on natural events such as droughts and urban floods. Resilience concept was then introduced to focus not only on defense system but also on the ability of urban areas to recover from negative events even though physical resiliencies not always accompanied with social resilience1.
Floods, now a days occurring all over the world, which requires special actions to re-design socio-economic development instead of physical development and to mitigate the negative impacts of flooding events. The Floodability concept can be adopted for India, which is defined as flood tolerance, integrating it with flood resilience.
As flood resilience is defined as the ability of a system to recover from a flood event, floodability can be defined as ability of the system to withstand floods in a part or in the whole system and still maintain sufficient level of service thus moving to a new equilibrium between populations and state variables in which flooding can be tolerated.
Floodability makes resilience-based management adaptive and a learning by-doing process: the floodable city is always a work in progress. In order to enhance urban floodability, investments in combinations of flood prevention and flood recovery have to be integrated with flood preparation measures . People are the main driver of social and economic evolution of the events.
People preparation to flood event handling is also a flood protection measure against unexpectedly severe events by adapting their strategies to the evolution of the events. In general, raising overall flood awareness among public bodies, citizen organizations, professional association, commercial and industrial corporations as well as technical experts will be precondition for involving them in flood risk management.
Floodability opportunities must be considered in the framework of risk management process, in which floodability is a group risk treatment option. It involves the causes, scales, and locations of a flood. Flood hazard maps have been produced for a long time and there are well established methods (e.g. Remote Sensing and Geographical Information System based methods) but hazard assessment approach also combines hydrological and hydraulic models at regional scale. To identify the floodability opportunities the “design to resist, pay for damage” approach should be replaced with following steps providing an evolution to resilient design:
If possible, reverse the urbanization process: such solutions entail high cost, occupation of large urban areas, a prepared population, cultural change and societal willingness to pay for past un sustainability
If transformation is not feasible, improve recovery ability: the aim is not to reduce the hazard but reduce the damage and speed up the recovery going towards resilient system. This approach usually entails lower costs than the revision option.
If flooding events are frequent, adapt and learn to live with the floods; such floodability measures have similar cost as adaptation. It is feasible in dense urban areas, but results cannot be achieved if societal behavior doesn’t change.
Urban planning must take flooding presence into account and urban materials must be different (sponge type to absorb excessive flooded runoff).
Technology can help, but measures must be robust (requiring low maintenance and efficient even if electricity or information technology are not available), and the population must be prepared because the right behavior in case of an event is the first mitigation measure (floodable society).
Data flowing into city must be used to better understand damage mechanisms and prevent future damage and improve citizen’s preparation for natural disasters.
Modern technology, such as up-to-date spatial planning techniques, crowdsourcing data collection methods and simulation models make possible to combine a large number of societal threats and optimize solutions to aid citizen to adapt and learn to live with natural hazards. Hence we can say, floodability doesn’t introduce new mitigation measures but provides a new perspective through which it is possible to combine them in a framework that combines societal, economic, environmental and technical aspects.
Er. Q. S. Wamiq Ali is currently working as a Technical Consultant in the field of Water Resources Engineering in National Water Mission, DoWR, RD & GR, Ministry of Jal Shakti handling NWM’s Goals: “Comprehensive water database in public domain and assessment of the impact of climate change on water resource” & ” Promotion of citizen and state action for water conservation, augmentation and preservation”. He has worked on several assignments related to hydrology, water resources engineering, water and sanitation, agricultural water management, urban water management, water and wastewater treatment including policy advocacy.
