Major rivers in Tamilnadu
The rivers of Tamil Nadu are its lifeline. Tamilnadu has many rivers. However, the notable ones are Cauvery, Palar, Ponnaiyar, Vaigai, and Thamirabarani.
Most of the rivers of Tamil Nadu originate from the Western Ghats flow towards the east and drain into the Bay of Bengal. Thamirabarani River is the only perennial river in the country.
Thamirabarani River is perennial because it is fed by both the southwest and northeast monsoons.
Cauvery
Cauvery originates at Talacauvery in the Brahmagiri hills of Kodagu (Coorg). Coorg is a district in Karnataka in the Western Ghats. About 416 Km of its course falls in Tamil Nadu. It serves as a boundary between Karnataka and Tamil Nadu for a distance of 64 Km.
Cauvery River forms Hogenakkal waterfalls in Dharmapuri district. Stanley Reservoir also called Mettur Dam is located across the Cauvery River in the Salem district.
A tributary called Bhavani joins Cauvery on the right bank about 45 km from the Mettur Reservoir. Thereafter, it takes an easterly course to enter into the plains of Tamil Nadu.
Two more tributaries, Noyyal and Amaravati confluence the river on the right bank at Thirumukkudal 10 km from Karur. The river is wider in this region, where it is called ‘Agandra Cauvery’.
In the Tiruchirappalli district, the river branches into two parts. The northern branch is called Kollidam or Coleroon. The southern branch remains Cauvery. From here, the Cauvery delta starts.
After flowing for about 16 km, the two branches join again to form ‘Srirangam Island‘. The Grand Anaicut, also called Kallanai was built across the river Cauvery. After Kallanai, the river breaks into a large number of distributaries and forms a network all over the delta.
The network of distributaries within the delta of Cauvery on the coast is called the ‘Garden of Southern India‘. It merges into the Bay of Bengal to the south of Cuddalore.
Palar

The Palar River rises beyond Talagavara village in the Kolar district of Karnataka. The Palar drains an area of 17,871 sq. km, out of which nearly 57% lies in Tamil Nadu and the rest in the states of Karnataka and Andra Pradesh.
Ponnai, Goundinya Nadhi, Malattar, Cheyyar, and Kiliyar are its major tributaries. Its total length is 348 km, out of which 222 km of its course falls in Tamilnadu.
Palar flows through the districts of Vellore and Kancheepuram. Finally, it enters the Bay of Bengal near Kuvattur.
Then Pennaiyar/Then Ponnaiyar
Then Pennaiyar originates from the eastern slope of Nandi Durga hills in eastern Karnataka and drains an area of 16,019 sq. km, of which nearly 77% lies in Tamil Nadu.
This river flows for a distance of 247 km in the southeasterly direction in the districts of Krishnagiri, Dharmapuri, Vellore, Tiruvannamalai, Cuddalore, and Villupuram.
Then Pennaiyar branches into two viz. Gadilam and the Ponnaiyar near Tirukoilur Anaicut. Gadilam joins the Bay of Bengal near Cuddalore and Ponnaiyar near Puducherry. Chinnar, Markandanadhi, Vaniar, and Pambar are its tributaries.
Heavy rain at the river’s source causes sudden but short-lived floods. The river is extensively dammed for irrigation, in Tamil Nadu.
There are reservoirs at Krishnagiri and Sathanur across this river. The Ponnaiyar is considered sacred by Hindus and festivals are held during the Tamil month of Thai (January-February).
Vaigai
Vaigai River rises from the eastern slopes of the Varusanadu hills of the Western Ghats of Tamil Nadu. It drains an area of 7741 sq. km, which lies entirely in the state of Tamil Nadu.
It flows through the districts of Madurai, Sivaganga, and Ramanathapuram. Its length is 258 km. It discharges its water into the Ramnad big Tank and some other small tanks. The tank surplus water is finally released into Palk Strait near Ramanathapuram.
Thamirabarani
Thamirabarani is named from Thamiram (copper) and Varuni (streams of rivers). The water of this river gives a copper-like appearance due to the presence of red soil suspended in it.
Thamirabarani originates from a peak in Pothigai Hills on the Western Ghats above Papanasan in the Ambasamudram Taluk. The origin of the river is associated with Sage Agasthiyar.
This river travels through the districts of Tirunelveli and Thoothukudi and finally flows into the Bay of Bengal near Punnaikayal in the Thoothukudi district. Karaiyar, Servalar, Manimuthar, Gadananathi, Pachaiyar, chittar, and Ramanathi are its main tributaries.
FAQ
a.How many rivers are in Tamilnadu?
There are 115 big and small rivers in Tamil Nadu. Of which there are Major 17 river basins in Tamil Nadu. Of the 17, Cauvery is the only major river basin, 13 others are medium basins and 3 are minor basins, which other rivers constitute.
b.Name some important rivers in Tamilnadu.
Cauvery, Palar, Vaigai, Noyyal, Cheyyar, Moyar, Bhavani, Thamirabarani, etc are major rivers of Tamil Nadu.
c.State river of Tamil Nadu?
There is no official state river for Tamil Nadu. But the Cauvery is its main river. It flows into Tamil Nadu from Karnataka and it flows one-third of the state.
d.Top 10 rivers in Tamilnadu?
Based on the length, the top 10 rivers in Tamilnadu are:
- Kaveri – 765 Km
- Ponnaiyar – 500 Km
- Palar – 348 Km
- Amaravati – 282 Km
- Vaigai -258 Km
- Bhavani – 215 Km
- Noyyal – 180 Km
- Tamirabarani -125 km
- Thirumanimutharu -120 km
- Arani – 108 Km
References
https://kids.britannica.com/students/article/Tamil-Nadu/337962