Kerala, a state in southern India known for its vast expanses of greenery, beaches, and tourism, was accustomed to heavy rainfall. However, the first 20 days of August 2018 saw almost 164% more rainfall than normal. With almost all of the dams being opened, around 500 deaths, and the worst flooding since 1924, the 2018 Kerala floods were truly one of the worst natural calamities in human history.
Flooding occurs when the downpour of water becomes so extreme that the ground below becomes saturated, unable to absorb any more water, before all the water drains away. Kerala in particular was in the midst of its annual four-month long monsoon season which meant it was already receiving a lot of rain when that amount drastically increased.
It usually takes a lot of rainfall for the level of a river to rise, but dry ground easily saturates. Although Kerala is dotted with 44 rivers throughout, it also has more than 50 dams. On either side of the dam, the water levels are different with one side significantly higher than the other. When the water level behind the dam is filled to capacity, water has to be released downstream. Because more than 30 dams were opened during the flooding, a tremendous amount of water flooded the villages below.
The unusually high amount of rainfall along with already filled dam reservoirs both contributed to the atrocities in Kerala. If the dam reservoirs had been emptier prior to the heavy rains, the amount of flooding may have been slightly reduced. Almost 57% of the dams in Kerala are used for hydroelectricity, electricity powered by the flow of water, and the other 43% are used for agricultural purposes. As a result, the amount of water stored in the dams’ reservoirs is determined by electrical and agricultural needs rather than the safe amount to avoid flooding. Dam mismanagement is blamed to have increased the harmful effects of the floods.
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