[Report of the Medical Officer of Health for Wanstead].

  • Wanstead (London, England). Urban District Council.
Date:
[1920]
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: [Report of the Medical Officer of Health for Wanstead]. Source: Wellcome Collection.

    6/32 (page 6)
    6 this most complete and up-to-date installation have fulfilled every expectation, and as a useful means of auxiliary treatment the Council still retain a large area of under-drained land for irrigation, and twelve old contact-beds (each 60 ft. by 44 ft.) The process now followed may be roughly summarised as follows :— The crude sewage from the whole of Wanstead flows to the Works through the old main outfall sewer (2 ft. 4 in. by 3 ft. 6 in.) traversing Wanstead Park, and the smaller main sewer of 18 in. which collects the sewage of the Aldersbrook and Lake House Estates. Passing through the detritus-tanks and their screens the sewage is relieved of all the coarse heavier solids, and then flows on to the settling-tanks where a further proportion of suspended matter is deposited. From here the liquid passes to the humus-tank where a final deposition of suspended matter occurs, and the effluent is now fit for treatment on the great percolating filters over which the liquid is sprayed in a thin film by the electrically-driven distributors which form perhaps the most interesting feature of the scheme. By this process of filtration, a clear, bright effluent is yielded which is suitable for discharge into the most jealously guarded water-course. In times of heavy sewage-flow or when it is desired to 'rest' the distributors, use can be made of the old contact-beds or the under drained grass-lands. Storm water is treated in a long scries of open tanks divided by weirs. To remove the sludge and other deposits from the settling tanks, humus-tank, etc., recourse is had to electrically-driven Stereophagus pumps which raise the thick and heterogeneous mixture with the most unfailing and surprising readiness on to the sludge lagoons where a natural drying process takes place. When the varied components and stiff consistency of the sludge are considered, it seems almost incredible that a pump of so small a bore should be capable of lifting and discharging the dense fibrous gritty paste without clogging or jamming. The wide interest caused by the unusual features of the Council's Works is proved by the visit recently paid by the Chief Engineer of the London County Council and his predecessor, Sir M. Fitzmaurice. All the work on the farm is carried on practically without noise, and as the Council have thoughtfully forbidden the use of guns the place has become a bird sanctuary. I have seen on the farm in my time the following less common birds : the Kingfisher, the teal and mallard ducks, the snipe, the heron, many varieties of finches, sand martins pied and yellow wagtails, and partridges. One of the older men on the farm has told me that the former farm manager captured a golden heron. This may have been a specimen of the bittern.