River Systems

            The river systems of India can be classified into four groups viz., (i) Himalayan rives , (ii) Deccan rivers, (iii)Coastal rivers, and (iv) Rivers of the inland drainage basin.

            Himalayan rivers are formed by the melting snow and glaciers , therefore  continuously flow throughout the year . During the monsoon months, Himalayas receive  very heavy rainfall and rivers swell, causing frequent floods.  Deccan rivers are rainfed and many of these are  non-perennial.  The Coastal streams on the west coast are short in length, have limited catchment area and most of them are non-perennial. The streams of inland drainage basin of western Rajasthan are of an ephemeral character.

             Indus rises near Mansarover in Tibet and flows through India & there after Pakistan and then falls into the Arabian Sea near Karachi.     

             Bhagirathi and Alaknanda , joins at Dev Prayaga to form the Ganga . It traverses through Uttarakhand , U.P., Bihar and W.B. states Yamuna meets Ganga at Allahabad.

            The Padma and the Brahmaputra join at Bangla- desh and continue to flow as the Padma or Ganga.

            The  Brahmaputra rises in Tibet, where it is called as Tsangpo, when it enters Arunachal Pradesh, it is called as Debang . Near Passighat , the Dihang and Lohit joins the river Brahmaputra. It croses in to Bangladesh downstream  of  Dhubri.  The Brahmaputra in Bangladesh fed by Tista, etc. finally falls into Ganga.

           The principal tributaries of Brahmaputra in India are the Subansiri, Jai Bhareli, Dhansiri , Puthimari ,Pagladiya and the Manas.

          The Barak river, the Head stream of Meghna, rises in the hills in Manipur.  The important tributaries of the river are Makku , Trang , Tuivai, Jiri, Sonai ,Rukni, Katakhal, Dhaleswari, Langachini, Maduva  and Jatinga. Barak continues in Bangladesh till the combined Ganga- Brahma- putra join it near Bhairab Bazar.

          The Godavari in the Southern Peninsula has the second largest river besin covering 10% of the area of India . Next to it are the Krishna, the Mahanadi, the Narmada and of the Kaveri are about the same size , though with different claracter and shape.

         Very few rivers drain into the sea near the delth of east coast and there are as many as 600 such rivers on the west coast.

          A few Rivers in the Rajasthan area do not drain into the sea. They drain into salt lakes andget lost in sand with no outlet to sea.  They are Luni, Machhu, Rupen, Saraswati , Banas, Ghaggar and others.

        The entire country has been divided into twenty river basins / groups of river basins comprising 12 major basins and eight composite river basins.

        The 12 major river are (1) Indus (2) Ganga -Brahmaputra- Meghna, (3) Godavari, (4) Krishna, (5) Cauvery ,(6) Mahanadi (7) Pennar , (8) Brahmani- Baitarani, (9) Sabarmati, (10) Mahi, (11) Narmada and (12) Tapti.

       The eight composite river basins combining suitably together all the other remaining medium and small river systems for the purpose of planning and management are :

          (1) Subernarekha ,
          (2)  East flowing rivers between Mahanadi and Pennar ,
          (3) East flowing rivers between pennar and Kanyakumari,
          (4) Area of Inland Drainage in Rajasthan Desert,
          (5) West flowing rivers of Kutch and Saurashtra including Luni,
          (6) West flowing rivers from Tapi,
          (7) West flowing rivers from Tadri  to Kanyakumari  and 
          (8) Minor rivers draining into Myanmar and Bangladesh.