What is Drainage System? Meaning, Basin & Water Divide – Class 9

Meaning of Drainage

1. Drainage means the way water is removed from an area.
2. In geography, drainage means the river system of an area — how rivers and their smaller streams carry water across the land.

 

River System

1. A river system means a big river along with the smaller rivers and streams that flow into it.
2. Together they make a network that carries water to a sea, lake, or ocean.

Example: Ganga River System

1. Main river → Ganga
2. Tributaries → Yamuna, Ghaghara, Gandak, Kosi, Son, etc.

How a River System Forms?

1. Small streams start from mountains or hills.
2. These streams join to make a main river.
3. The main river finally carries its water into a larger water body such as a lake, sea, or ocean.

Drainage Basin

1. A drainage basin is the land area where all rivers and streams collect rainwater and bring it to one main river.
2. It works like a natural water-collecting bowl.

Water Divide

1. The term water divide refers to elevated ground that acts as a boundary between the catchment areas of two river systems.

Example:

1. In Haryana, the Ambala district forms the dividing line between the Ganga basin and the Indus basin.

✅ In Short:

1. Drainage = River system of an area
2. River System = Main river + tributaries
3. Drainage Basin = Water-collecting area of a river system
4. Water Divide = High land separating two river basins