BANSAGAR DAM

VT LONDHE FEBRUIARY 1983–OCTOBER 1985

General

This 63 m high dam project is located across Sone river in MP on the border of Satna and Shahdol districts. This project benefits irrigation in the three states of MP, Bihar and UP and funded by these three states in the ratio of 2:1:1 respectively. The speciality of this project is that it is located D/S of the geological fault in the river bed itself. Further I could know from the Resident Geologist that this fault is of an international nature. This actually extends from the river Sone and going westwards through rivers basins of Narmada, Tapti, Mahi, Pranhita and Godavari and then from below the bed of the Arabian sea to the Africa in the river Nile also.

Achievements

I was posted to this project for the construction of the left and right flanks of the masonry dam. Here also the surplussing arrangements for the energy dissipation arrangements were of the similar type to that of the Bargi Project. The actual construction of such slotted roller bucket for the energy dissipation arrangements we could complete with confidence. The leaving of the pier block outs in the masonry was a challenging task particularly while executing masonry. The masonry work had to be stopped for a while at different locations and also at different levels. The execution work of the glacis concrete was an uphill task particularly with vibration,form work and the final shape of the glacis.

Special Works

A very important fact in this project is that the masonry has been executed out of very good sand stones of more or less of a cubical shape. The masonry was found to be absolutely impervious particularly because of the fact that the stones were got vibrated manually by labourers with 3/4 inch steel rods so that no voids are allowed to be left inside the masonry with the result that the mortar consumption was actually of the order of 42% the same as is theoretically required. This fact was not initially believed by the officers from the CWC New Delhi. And as such when they visited this project, they were requested by us to get checked this fact by drilling through the masonry and checking the permeability themselves. To their surprise they found the masonry to be completely impervious.