Types of Drainage Systems of India

Usually the drainage systems can be classified on different basis. Here the drainage system of India was classified into three kinds. The first one was the division made by K . L. Rao and it was on the basis of the catchment area size of the drainage. The second division is the most common division everybody knows and that is the division was made on the basis of the origin of the drainage system. The third and may be the final division was made on the basis of orientation to the sea.

There are many small to large rivers in India and these are the most useful natural resource. In India all the areas that were highly fertile are on the bank of these rivers. Now let us see in brief how these rivers in India were classified basing on the categorization that was given above.

K. L. Rao has made this division. He divided the rivers in India basing on the size of the catchment area and placed all these rivers in three categories. He named the categories, major river basins, medium river basins and minor river basins.

Major River Basins: Those river basins with 20,000 sq km and above catchment area were placed under this division. These rivers of India account for 85% of all the rivers’ total run-off. These rivers lie mostly in the areas of high rainfall. There are 14 rivers that come under this category. Three among these rivers were in the northern part of India and above the tropic of cancer. Seven of these river systems lie in between the tropic of cancer and the latitude of 20 deg north. The remaining four river systems can be seen in the peninsular India.

Medium River Basins: Those river basins with the area of catchment between 2000 sq km and 20,000 sq km come under this division. These systems account for 7% of the total run-off of all the Indian rivers. There are 44 rivers that come under this category. These rivers lie in the areas that have medium rainfall. The rivers under this division are further divided into three more sub categories based on their flowing direction. The first category is the west flowing rivers and 19 rivers were placed under this category. There are east flowing rivers which are 21 in number and they were in the second sub category. The final sub category has 4 rivers and they flow into the other countries.

Minor River Basins: Those river basins with a catchment area under 2000 sq km are under this division. These rivers account for 8% of the total run-off of the rivers that flow in India. There are many river under this division and they probably can be seen in the dry areas and the coastal areas.

This classification is the most common one and has two major sub categories namely the Himalayan Rivers and The Peninsular Rivers.

The Himalayan Rivers: Those rivers which have their origins from the hills of Himalayas come under this category. The major rivers under this sub category include Indus, Brahmaputra and Ganga.

The Peninsula Rivers: Those Rivers having origins from the hill areas that lie in the region of peninsular India were placed under this sub category. Major river systems under this division include the Godavari, the Narmada, and others.

This division of Indian River systems was mainly sub divided into two categories based on the river systems and their orientation to the sea. Two major categories under this division are The Bay of Bengal Rivers and The Arabian Sea Rivers.

Orientation to Bay of Bengal Sea: Those Rivers which flow into are oriented towards the Bay of Bengal come under this sub category. Nearly 77% of the river systems in the Country are under this category. The major rivers like Ganga, Brahmaputra, Mahanadi, Godavari, Krishna, Kaveri etc come under this category.

Orientation to Arabian Sea: Those Rivers which flow into the Arabian Sea are oriented towards the said sea come under this category. 23% of the system was placed under this category. The rivers such as Narmada, Indus Subarmati, Tapi etc come under this sub division.