The drainage system (Drainage Patterns) is an integrated system of tributaries and a trunk stream which collects and funnels the surface water to the sea, lake or some other water body. The total area that contributes water to a single drainage system is known as a drainage basin. In other words, the flow of water through well defined channels is known as drainage and the network of such drainage channels is known as a drainage system.
A river drains the water collected from a specific area which is called its catchment area. The boundary line separating two drainage basins is known as a watershed. There are majorly 6 types of drainage patterns. They are:
1. Dendritic Drainage Pattern: It is a type of drainage which is branching, thereby giving the appearance of a tree. Most of the rivers of Indo Gangetic plains are dendritic in nature.
2. Trellis Drainage Pattern: Trellis is a rectangular pattern formed where two rivers meet at right angles. In this, the river forms a net like system and tributaries flow roughly parallel to each other just like the drainage pattern of the Singbhum Mountains.
3. Radial Drainage Pattern: It is a drainage pattern characterized by out flowing rivers, away from a central point analogous to the spokes of a wheel. Rivers originating from Amarkantak are good examples of this drainage pattern.
4. Annular Drainage Pattern: In this drainage pattern, the subsequent streams follow curving courses prior to joining the consequent stream. These types of rivers are found in Pithoragarh (Uttaranchal) and the Nilgiri Hills (Tamil nadu & Kerala).
5. Parallel Drainage Patterns: It is a drainage pattern in which rivers flow almost parallel to each other. These include the small and swift rivers of the Western Ghats.
6. Deranged Drainage Patterns: This is an uncoordinated pattern of drainage characteristic of a region recently vacated by an ice sheet. It is quite common in glaciated valleys of Karakoram ranges.