A watershed is the geographic area through which water flows across the land and drains into a common body of water – stream, river, lake, or ocean. The watershed boundary follows the highest ridgeline around the stream channels which separates the water flow which may be basically rainwater, groundwater, water from melting snow etc. and meet at the bottom or lowest point of the land where water flows out of the watershed. Watershed can be as small as few hectares as in case of a pond or may be as large as hundreds of square kms as in case of rivers.
Watershed management refers to efficient management and conservation of surface and groundwater resources. It involves prevention of runoff and storage and recharge of groundwater through various methods like percolation tanks, recharge wells, etc. However, in broad sense watershed management includes conservation, regeneration and judicious use of all resources – natural (like land, water, plants and animals) and human within a watershed. It brings about the balance between natural resources on the one hand and society on the other through community participation.