Rivers in Orissa serve the basic require- ments of the state. They play a vital role in prospering the state’s agrarian economy. All the rivers of Orissa have common characteristics-they all are Monsoon Rivers. In the hot weather they are beds of sand with tiny streams or none at all, while in the rains they receive more water than they can carry. The major rivers of Orissa are:
The Mahanadi:- It is the largest river of Orissa and the sixth largest river in India. It is originated from the Amarkantak Hills of the Bastar Plateau in Raipur district of Chattisgarh. It is about 857 kms. long (494 kms. in Orissa) and its catchment area spreads over 141,600 sq.kms (65,580 sq.kms in Orissa). The river carries on an average about 92,600 million m of water. It enters into the Bay of Bengal.
The Brahmani:- It is the second largest river in Orissa. It originates as two major rivers like the Sankh and the Koel from the Chotanagpur Plateau of Bihar and both join at Veda Vyasa near Rourkela of Sundargarh district of Orissa forming the major River Brahmani. It flows through the Eastern Ghats in Sundargarh, Keonjhar, Dhenkanal, Cuttack and Jajpur districts into the Coastal Plains and enters into the Bay of Bengal along with a combined mouth with the Mahanadi known as the Dhamra. The Brahmani is 799 kms long (541 kms in Orissa) and its catchment area spreads over 39,033 sq.kms in Orissa.
The Baitarani:- It originates from the Gonasika Hills of the Keonjhar districts. It is 365 kms long and its catchment area spreads over 12,790 sq. kms . It enters into the Bay of Bengal after joining of the Brahmani at Dharma mouth near Chandabali.
The Subarnarekha:- It originates from the Chotanagpur Plateau of Bihar. It is 433 kms long (70kms in Orissa ) and has a catchment area of 19,500 kms (3,200 kms in Orissa ) with a mean annual flow of 7,900 million m of water. It enters into the Bay of Bengal.
The Budhabalanga:- It originates from the Eastern Slops of the Similipala massif. It is about 175 kms long having a total catchment area of 4840 sq. kms with an annual flow of 2177 million m of water. It’s major tributaries are the Sone, the Gangadhar, the Catra etc.
The Rushikulya:- It originates from the Rushyamala Hills of the Eastern Ghats in Phulbani district. It is 165 kms long with 8900 sq. kms of catchment areas. It’s tributaries are the Baghua, the Dhanei Badanadi etc. It has no delta at its mouth.
The Bahuda:- It originates from the Ramgiri Hills of the Eastern Ghats in Gajapati districts and joins the Bay of Bengal in Andhra Pradesh . Its length is 73 kms having a catchment area of 1250 sq. kms .
The Bansadhara:- It originates from the Flanks of the Durgakangar Hills (Lingaraj Hills) of the Eastern Ghats in Kalahandi districts. It is 230 kms long out of which only 150 kms is in Orissa. It enters in to the Bay of Bengal at Kalingapatnam in Andhra Pradesh. It has a catchment area of 11500 sq. kms .
The Nagabali:- It originates from the Bijipur Hills of the Eastern Ghats near Lanji Garh. It is 210 kms long out of which 100 kms is in Orissa. It has a total catchment area of about 9410 sq. kms.
The Salandi:- It originates from the Meghasani Hills of the Similipal Massif in Keonjhar district. It is 144 kms long with a catchment areas of 1793 sq. kms.
The Indrabati:- It originates from the Eastern Ghats in Kalahandi district. It is 530 kms long with a catchment area of 41700 sq. kms and as a tributary it flows into the Godavari River.
The Kolab:- It originates from the Sinkaran Hills of the Eastern Ghats in Koraput district. It has catchment areas of 20400 sq. kms.