Floodwater Management In Pakistan Due to global climate change and rapid urban growth, Pakistan is hit by catastrophic floods every year, causing millions of people to suffer massive losses, be they physical, emotional or financial. Floodwater management must therefore become part of the overall sustainable master planning of urban and rural areas, and several solutions can be employed to minimise the damage caused by floods.
These include:
* Deforestation is a major contributor to floods in both rural and urban environments. Trees promote water absorption into the soil and prevent flooding; therefore, a planned approach to planting more trees to reverse the effects of deforestation must be implemented.
* Drainage systems must be be redesigned to release water into the soil beneath the city or stored, so that it can be used in case of water shortages.
* The capacity of flood defences (such as dams, river barriers and diversion channels) must be increased significantly to accommodate rising amounts of floodwater.
* Unplanned, informal levees have been constructed by farmers along many rivers in Pakistan; these contribute to flooding by preventing the surplus water from returning to the river after excessive rainfall. To remedy this, planned channels with with properly filtrated stroge reservoirs, both above and underground, should be constructed. These reservoir will be especially beneficial to large rural populations that require controlled amounts of water throughout the year for their fields, crops and livestock.
* In strictly urban contexts, building material such as asphalt and concrete prevent water from being absorbed into the soil, leading ti floods and creating ‘heat islands’ (urban areas that are warmer than their rural surroundings). These material should, therefore, be used sparingly.
* Cities such as Rotterdam have created dual purpose areas such as underground parking, rooftop gardens and parks to combat flooding by serving as reservoirs during floods.
For example, the Rotterdam Museum Park has a basement garage that functions as a water reservoir capable of storing 10 million litres of storm water. Such innovative strategies must now be part of the urban planning in Pakistan.
By Amena Nadeem The write is an architect at Studio Subtractive