Mr. W. H. Power's report to the local government board on epidemic prevalence of diphtheria in North London.

  • Power, W. H.
Date:
1878
Catalogue details

Licence: Public Domain Mark

Credit: Mr. W. H. Power's report to the local government board on epidemic prevalence of diphtheria in North London. Source: Wellcome Collection.

Provider: This material has been provided by London School of Hygiene & Tropical Medicine Library & Archives Service. The original may be consulted at London School of Hygiene & Tropical Medicine Library & Archives Service.

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    ZS4 4 can hardly be said to have suffered disproportionally to dwellings far removed from the nuisance complained of. The one exception above made relates to sewers and drains of the infected area. Herein there were found conditions of defect of a nature liable to do injury to health, and very much localised in the particular area of the epidemic. The history is as follows:— At the western extremity of Alexandra Road, St. John’s Wood, two main sewers, 6 ft. X 5 ft. 6 ins. and 6 ft. X 5 ft. respectively, coalesce to form a single circular sewer, which for a course of 450 ft. has an average diameter of 4 ft. 6 ins.; afterwards this sewer expands to 7 ft. diameter. Of the two sewers thus undergoing constriction at their outlet, one drains a comparatively limited area to the northward—Kilburn Yale and neighbourhood; the other receives from the north and east contributory sewers from about one half the area of Hampstead parish, east of the Finchley Road, and in addition receives from the southward the Abbey Road sewer draining a large portion of St. John’s Wood. The special sewage area thus constituted corresponds in its inhabited parts pretty closely to the area defined by the inner circle. Except small portions on the east and west confines, this sewage area occupies the whole of that circle, and though extending northwards into the outer ring, it has not in that region any considerable population. Altogether, of the 2,700 dwellings in the inner circle, this special sewage area comprises’ some 2,000. The sewers of this area are generally ill-ventilated. Openings at the street level are rare; such ventilation as is obtained being by means of street gullies, nominally but inefficiently trapped. There is no systematic flushing of these sewers. As regards private drainage, trapping of drain inlets within houses has commonly been relied on for securing dwellings against entrance of sewer air, adequate ventilation of house drains having been generally neglected. Of course there are exceptions (and among them not a few in households invaded by throat illness) where, in conjunction with trapping, care has been exercised in duly ventilating the house drainage. But too often the ventilation adopted has been restricted to a single ventilating orifice; and as regards trapping, kitchen and housemaid’s sinks have frequently been merely provided with bell-traps. In addition wastepipes from cisterns and baths have been found in several instances to com- municate directly with drains. In short, dwellings in this area, as in London generally, must be held to be commonly, under circumstances of unusual pressure within ill-ventilated sewers, very inefficiently protected against entrance into them of sewer air. Under conditions of public sewerage and private drainage of the above sorts, the special area cannot have failed to have been repeatedly, if not continually, exposed to sewer and drain nuisances; for the liability of the main sewers to strangulation at their outfall under exceptional rainfall must have frequently conduced to extensive backing up of sewage and penning up of foul air within the ill-ventilated sewers, and hence to forcible expulsion of the pent-up sewer air by the way of unventilated house drains and inefficiently trapped orifices into the dwellings of the district. As a fact strangulation in the above sense, and of a serious sort, of these particular sewers at their outfall occurred as a result of the notable rainfall of 10th and 11th April last. On this occasion the surveyor of Hampstead Vestry has shown that the chief of the sewers referred to (that draining St. John’s Wood and South Hampstead) usurped altogether the circular outfall sewer, retarding the flow from and even producing a back current in its companion sewer from the Kilburn Yale district, which subsequently was found partially silted up for a considerable distance. The most conspicuous result on this occasion seems to have been serious flooding of the basements of low-lying houses near Kilburn Station ; and, in addition, rupture of a pipe sewer at a higher level in Priory Road occurred with further flooding of basements in that neighbourhood; but there is good ground for believing that mere flooding did not represent the whole mischief thus caused. Blocking of the main sewer outlet for this district to the extent indicated by the flooding must have caused immense pressure over a large area within the sewers, and sewer air can hardly have failed to have been driven out into dwellings over a large portion, if not over the whole, of the area served by these sewers. That something of this sort did take place there is abundant evidence, though such result did not generally attract notice. Clearly, if sewer air be by itself capable of causing throat illness, persons resident in the special sewage area must, as a result of the obstruction at the sewer outfall on 11th April, have been exposed beyond all persons resident in the district under consideration to special risk of attack by the disease. The incidence of throat illness on the special sewage area, on the remainder of the