The drainage and sewerage 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 drainage and sewerage of Bombay : being a report submitted to the Bench of Justices of that city / by their Executive Engineer Hector Tulloch. Source: Wellcome Collection.

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    ago a small low-level sewer for use during dry weather. The very wide section of the large drain and its small fall caused the sewage to flow so sluggishly that it was con- sidered advisable by Mr. Aitken, then Executive En- gineer to the Municipality, to construct a smaller sewer with a greater fall. The bottom of the large drain being at the level of low water of spring-tides, it will at once be seen that the outlet for the drainage is not always free. Only^ when the tide is at its very lowest can the drain empty itself thoroughly. At neap-tides the water stands several feet deep in the drain, and only a partial discharge takes place. The small new sewer has its bottom at a still lower level than the open drain, and it could never discharge itself into the sea. It was not built with this object. It was simply built in order to bring the sewage more rapidly to the outlet than before. The sewage is raised from the small sewer by steam-pumps during eight or nine months of the year, de- pendent on the duration of the monsoon, and then flows mto the sea. During the rainy season the work of pumping is stopped, and both drainage and sewage escape along the open drain and through the sluices. The low-level sewer remains fidl of foul matter, and even under pressure, till the monsoon has cleared off, when pumping is resumed. Although the main sewer is 20 feet wide and 10 feet high, still, in heavy floods, it is not capable of discharging all the rain which falls on its drainage area. Parts of even the town itself are for many hours under water.^''' Of course m dry weather, just the opposite state of things prevails. The sewer having then to carry away nothing but the sewage of the town, it is enormously too large for the purpose.^ ihe sewage in it is but a few inches deep. In fact, what is the case in Bombay must be the case in nearly every town m * I have seen the sewer full up to the -own of the avch, and have stood in watev 3 feet deep in one of the streets near Grant Koad.