Watershed Analysis is performed to determine “Water Storage Site”. If You want to store water for your community, in a hilly area with side by streams which point/site you think is appropriate to store water. Watershed Analysis can solve your problem.    Image by  Claudio Bianchi  from  Pixabay     What it does: It uses a Digital Elevation Model  available freely online, and calculates watershed of area. It is done by following steps          Flow Direction (Calculates Direction of Flow at each raster)   Flow Accumulation (In each individual pixels how much pixels are contributing flow)   Snap Pour Point (Based on terrain select points with maximum Flow Accumulation )   Watershed Calculation (This tool will calculate area contributing to your snap point)              imagesource:  www.lutraconsulting.co.uk   Tutorials:  This blog  in detail explains all steps with visual images.     
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