The water-supply of Bombay : being a report submitted to the Bench of Justices of that city / by their Executive Engineer Hector Tulloch.

  • Tulloch, Hector.
Date:
1872
Catalogue details

Licence: Public Domain Mark

Credit: The water-supply of Bombay : being a report submitted to the Bench of Justices of that city / by their Executive Engineer Hector Tulloch. Source: Wellcome Collection.

    27/358 (page 7)
    There now steps on the scene a man who took a very different view of the state of things, and who not only under- stood the alarming nature of the patient's case, but made a proposition which ultimately grew into the present water- supply of Bombay. Captain (afterwards Colonel) J. EL G. Crawford, of the captam.crawfora-3 Engineers, leaving the wells and tanks in the town to take care of themselves, proceeded out of the Island, and, following the course of the stream which formerly took its rise near the village of Vehar, proposed to intercept it at a point not far from Kooiia. Here the water was to be pumped up and brought under pressure into Bombay by iron pipes. The dam was not to be built to retain any large quantity of water, but merely to give sufficient depth to pump from. This supply every year could of course last so long only as the stream continued to flow, or from the setting in of the monsoon up to about December. For the supply of the town during the other months a series of reser- voirs were to be formed along the course of the stream above the dam, and, as the stream dried up, the water in these reservoirs was to be led down to the lowest one where the pumps were to be placed. An alternative scheme suggested by him was to drain the Koorla valley by a system of underground channels to the point where the water was to be pumped up. He said:— Suppose a valley, as in the accompanying rough sketch, the nature of the soil being what I imagine it, I should sink a shaft (A) at the lowest point whence 1 wish to draw my water—in the present instance it would probably be 15 or 20 feet deep. I should then run an open drain (A B) 2^ feet wide, and as deep as circumstances would admit of, with a slight slope downwards towards A, building up the sides if necessary, and covering the surface with flagstones and earth; and at certain distances I would in like manner open the shorter cross drains (c d). In this way, looking at the bed of the valley as a vast sponge, the whole would be thoroughly drained without any loss from evaporation.