Why do water levels rise during a Monsoon?
The term 'monsoon' is commonly used to refer to the extremely rainy season observed in several parts of the world. When the rainfall takes place, the water can either be collected on the paved and hard surfaces and be removed through sewers, result in surface runoff, or it may infiltrate into the ground surface.
Among these pathways, the water that results in surface runoff typically ends up in surface water sources. The infiltrated water reaches the water table and thus the subsurface water sources. In both cases, the rainwater adds to the existing reservoir of water, whether on the surface or below the ground. This additional amount of water causes an increase in the water level.
The water level increase in the surface sources, such as streams and rivers, is very easily observed and occurs during the time of monsoons and may also cause flooding in some regions. Groundwater, on the other hand, will show an increase in the water level after some time, since it takes some time for the rainwater to reach the water table.
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