More information on the river can be had from the "Gazeteer of South India". The following is the excerpt from the above reference with additional information for the readers.
Excerpts from "Gazeteer of South India" by W. Francis et. al, pp.179-180.
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Tambraparni: A river in Tinnevelly District, Madras. The derivation of the name has been much discussed. One etymology is from the Sanskrit tamara, 'copper' and varna, 'colour', from the colour of the sand in its bed. It rises on the slopes of the peak Agastyamalai in the Western Ghats in 8 Deg 37 Min N and 77 Deg 15 Min E, and after a course of some miles through this range descends to the plains in five beautiful falls at Papanasam, a very sacred spot. Higher up, in the heart of the hills, it forms another falls called the Bana-tirtham, which is equally sacred but, being with difficulty accessible, is less frequented. From Papanasam it runs eastward across Tinnevelly District, receiving as it goes a number of tributaries which, like itself, rise in the ghats. The chief of these is the Chittar, 45 miles long. It eventually falls into the gulf of Mannar in 8 Deg 40 Min N and 78 Deg 9 Min E, after a course of 70 miles, during which it drains 1739 square miles.
The Tambraparni receives a supply from both monsoons, and is thus almost a perennial stream and of great use for irrigation. Eight dams across it. Seven of these were made by former native governments and are believed to date from the fifteenth century. The eighth and lowest, at Srivaikuntam, was suggested by Mr. Puckle, a former Collector, and was begun in 1867. It is 1,380 feet long, and feeds channels on both banks of the river, which fill a large series of tanks in which the supply was formerly precarious, and also water other land directly. The irrigation revenue has by this means been raised from Rs. 80,000 to over 2 lakhs, which gives a return of over 6 per cent on the capital of 15 lakhs laid out on the system. The Marudur dam, higher up the stream, irrigates on an average 30,000 acres of first and second crop, and the other six water 71,000 acres between them. One-tenth of all the irrigable area in Tinnevelly depends upon the river. Its vally is the wealthiest portion of the District, and the land there is some of the most valuable in the Presidency.
Several of the chief towns of the District stand upon the banks of the Tambraparni. Five miles below Papanasam are Ambasamudram and Kallidaikurichi, opposite one another and connected by a bridge built by public subscription in 1840; 20 miles farther down Tinnevelly and Palamcottah are similarly connected by the Sulochana bridge, built in 1844 by Sulochana Mudaliyar, a rich landowner and high official of the District; and there is a third bridge over the Srivaikuntam dam. Near the mouth of the river is Kolkai, the first capital of the Pandyas, the earliest seat of Dravidian civilization, and once a famous seaport. The silt from the river ruined its career as a port and it is now five miles from the sea; its place was taken by Kayal, where Marco Polo landed, but this also silted up and the Portugese then established Tuticorin as the chief port on this coast. The pearl and 'chank' (Turbinella rapa) fisheries off the mouth of the Tambraparni were once very famous and are frequently mentioned in early Tamil literature.
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