General report on the sanitary condition of the town of Kelso / drawn up at the request of the Board of Commissioners of Police, by Charles Wilson, M.D.

Wilson, Charles, 1804-1883

Date:: 1848

Credit: General report on the sanitary condition of the town of Kelso / drawn up at the request of the Board of Commissioners of Police, by Charles Wilson, M.D. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

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$Jiortlon to tlic quautity of water which roaches its area, wlicther iu the form of i aiii, or of discharges from natural si)rings, or from arti- ficial reservoirs and conduits. Two and a half millions of gallons would, it ajipcars to nio, be a tolerably wide estimate of the maxi- mum quantity of water thus falling at any time within our area of drainage, iu the space of twenty four hours. But wo ought to be provided for the delivery of a quantity exceeding this by at least a lialf, or approaching to four millions of gallons; because we ought not, in prudence, to bo considered as allowing any pro{)ortion for that which is again instantly absorbed by the earth, or is retained tcm]iorarily in the cisterns of the inhabitants, or finds its way to the ri\'er by other channels, and because in storms the rain must frequently descend in sudden dashes, requiring more than ordinary facilities for its rapid transmission. Let us concede that the two present sewers, proposed to be retained, are capable of transmitting a fourth part of this quantity, at which they would be considerably under-rated, and we have still a supposed amount of about three mil- lions of gallons for which to provide an exit. But T find that a tube, having an interior measurement of 25 by IG inches, and moving its current at the rate of only two miles an hour, will discharge, at a computation sufficiently accurate for our purpose, a daily amount of nearly three and a half millions of gallons. It appears evident, then, that a channel of these diniensions, vnth. due attention to the adjustment of its levels, could scarcely fail to sufHce amj)ly for our utmost exigencies ; and I would estimate its efficiency, with respect to its powers of transmission merely, at twice the extent of that Avhich it is designed to supersede. Were we to confine our estimate to the ordinary functions of such a conduit, apart from the eiFcet of storms and rapid thaws, it is obvious that a much smaller size would be fully adequate. As to the course of the sewer, it is probable that it will be con- sidered advisable to continue it in nearly its present line eastward : not so much on account of the advantages of the levels, as because it is in this direction that any possible future extension of the town is likely to jiroceed. A shorter course, certainly, and therefore a less expensive one, might be obtained along Hogg's lane; but, perhaps, the narrowness of the passage here would render it diffi- cult to descend to the requisite depth for laying the tubes. In whatever lino the sewer approaches the town, it ought to reach its outskirts at a point as far below the surface as can be rendered consistent with a proper declivity ; and not witliin a few inches of the plane of the houses, as under the present inefFoctive and perni- cious arrangement. Allowing, in this part of its course, a minimum descent, of three quarters of an inch for each ten feet of progress, which experience in the sewerage of other towns has proved to be amply sufficient for drains of this magnitude, there can be no diffi- culty iu causing it to cuter the town at a distance of not less than$