Flood is the catastrophic event would have the biggest impact on its watershed.
Flood is the overflow of water from the water resources such as rivers, lakes, and oceans.
It is one of the natural disasters that happen due to access of rain or breaking of dams etc.
Flood can affect the quality of water, there become scarcity of clean water.
People lost their home due to entry of water in the homes.
Thus, the catastrophic event is flood.
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