Bsce 4b: Rommelyn Joyce Fernandez

ROMMELYN JOYCE FERNANDEZ

BSCE 4B

WHAT IS WATERSHED?  It’s a land area that channels rainfall and

snowmelt to creeks, streams, and rivers, and eventually to outflow points such as reservoirs, bays, and the ocean.  It is a region or area drained by a river, stream, etc.  A watershed is the area of land where all of the water that falls in it and drains off of it goes to a common outlet.

 The word watershed is sometimes used

interchangeably with drainage basin or catchment.  Ridges and hills that separate two watersheds are called the drainage divide.  Larger watersheds contain many smaller watersheds. It all depends on the outflow point; all of the land that drains water to the outflow point is the watershed for that outflow location.

An example is the largest watershed in the United States is the Mississippi River Watershed, which drains 1.15 million square miles.

Shown here: an aerial view of Drakes Bay, part of California's Tomales-Drake watershed.

La Mesa Watershed Reservation in the PHILIPPINES

 The size of a watershed is defined on several scales—referred to as its Hydrologic Unit

Codes(HUC)—based on the geography that is most relevant to its specific area.