Periyar Project
This article has been extracted from THE IMPERIAL GAZETTEER OF INDIA , 1908. OXFORD, AT THE CLARENDON PRESS. |
Note: National, provincial and district boundaries have changed considerably since 1908. Typically, old states, ‘divisions’ and districts have been broken into smaller units, and many tahsils upgraded to districts. Some units have since been renamed. Therefore, this article is being posted mainly for its historical value.
Periyar Project
The Periyar ('big river') is a river of Southern India which rises on the western side of the range of the Western Ghats, and flows down to the Arabian Sea through the Native State of Travancore. The area through which it passes is within the zone of the heaviest rainfall in the south of India, and the crops there are grown by the aid of rain alone and without irrigation. Consequently the water of the Periyar ran uselessly to the sea. The great project to which the river has given its name consists in the construction of a huge masonry dam across the upper waters of the river, in Travancore territory, forming a great lake, and taking the water of this lake through a tunnel in the Western Ghats across to the opposite, or eastern, slope of that range to supply the arid areas which lie immediately below it on that side. In short, a great river which formerly ran down one side of a mountain range has been bidden to turn back and flow down the other side of it.
The lake has an area of 8,000 acres in Travancore territory, which land has been rented from that State for Rs. 40,000 per annum. The height of the dam, which is situated in 9 32' N. and 77 7' E., is 173 feet, and it is made of solid masonry throughout. The tunnel through tfie Ghats is 5,704 feet long, and the open cutting 01 debouchure on the northern side which leads to it from the lake adds 500 feet to its length. The tunnel proper has an entrance sluice 12 feet wide by 7^ feet high and a gradient of i in 75, anc is drilled through hard granite. The bed of the Vaigai river if utilized for some distance to carry the water to places where is is wanted, and the scheme includes in addition 36 miles of main canal and 190 miles of distributaries. Up to 1904 the total capital cost of the Project had been 92 lakhs.
The scheme was suggested as early as the commencement of last century, but was at first thought to be chimerical. It was revived in 1862, but it was not until 1882 that a beginning was seriously made with the preparation of estimates for the Project. The success of the work was mainly due to the efforts of Colonel Pennycuick, R.E., C.I.E., Chief Engineer to the Madras Government It was carried to completion in the face of enormous difficulties, the country being entirely uninhabited and most inaccessible, the climate infected with deadly malaria, the difficulty of getting labour and transport immense ; and many of the technical problems involved in the work were of an entirely new description. The foundations of the dam were carried away time after time before they had proceeded suffi- ciently to be out of the reach of floods, and unforeseen difficulties and trials had constantly to be met and overcome. The official History of the Project, by Mr. A. T. Mackenzie, one of the staff of engineers who carried it to completion, gives a full account of the undertaking and the manner in which it was effected.
It is too soon as yet to judge of the financial result of the Project, as the whole of the land commanded has not yet been prepared for ' wet ' cultivation by the ryots and so cannot be supplied with water. At the end of 1903-4 the total area of land irrigated, including second -crop cultivation, was 142,000 acres, and the net revenue was Rs- 3,55,000 giving a profit of 3-86 per cent, on the capital outlay. The total cultivable area commanded by the main canal and its twelve branches is 121,000 acres, including land of all classes. The supply available is probably sufficient for only about 111,000 acres; and the most important problem that now remains is concerned with the extension of the system, by forming a second reservoir in which to store the surplus water which still runs to waste.
