Report of the Medical Officer of Health on the public health and sanitary circumstances of Johannesburg.

  • Johannesburg (South Africa)
Date:
[1937]
Catalogue details

Licence: Public Domain Mark

Credit: Report of the Medical Officer of Health on the public health and sanitary circumstances of Johannesburg. Source: Wellcome Collection.

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    or, Klipspruit Works. Due to the increase of contributing population the flow to these works has increased by more than 20 per cent., and the irrigable lands are now being dosed to the maximum. When the new works are put into operation, and a portion of the final effluent diverted to the proposed new power station for cooling water, the position will be somewhat improved. The revenue produced from grazing was £8,558, and the total from all sources £9,268, showing a decrease of £773 compared with the preceding year. This decrease was caused by a falling off in revenue from grazing fees on account of a general plentiful supply of grazing due to a good grass growing season. During the year 983 acres have been ploughed, disked, and harrowed by mechanical means, and 14,000 lbs. of Italian rye grass seed sown. The work of lining earth effluent carriers with semi-circular concrete channels, each 3 feet long, was continued, 2,582 channels being laid, bringing the total length of concrete lined effluent carriers up to 27-4 miles. Pilot Plant. The experimental settlement tank, open percolating filter and “ Truss ” enclosed filter were ready for operation in the middle of September, 1936. The trials will be continued in order to provide data for the modernisation of the Klipspruit treatment plant. KLIPSPRUIT PILOT PLANT. Data Sheet. Settlement Tank. Diameter, 20 feet 9 inches. Total depth, 24 feet. Depth of cylindrical top, 6 feet 6 inches. Slope of conical sides, 60 degrees. Capacity, approximately 26,400 gallons. Open Percolating Filter. Diameter, internal, 40 feet. Height of walls (brickwork), 6 feet 14 inches. Floor sloped outward, 1:60. Central chamber, 5 feet 6 inches diameter external, contains supporting column for distributor. Aerating Floor, semi-cylindrical tiles 8 inches diameter, carried through walls. Medium, bottom layer 12 inches of 8-inch to 6-inch mine stone. Upper layer 4 feet of 24-inch mine stone. Cubic yards of medium (less tiles) 267. Distributor, Simplex Patent Mercury Seal four-armed type. Enclosed Pruss Filter. Diameter, internal, 40 feet. Pleight of walls (reinforced concrete), 20 feet. Concrete roof sloped 1:4. Floor sloped to centre 1:40. Aerating floor, semi-cylindrical 8-inch tiles carried through wTalls. Medium, bottom layer 1 foot 6 inches of 3-inch to 6-inch mine stone. Middle layer 12 feet of 2^-inch mine stone. Top layer 1 foot 6 inches of 2-inch to 8-inch mine stone. Cubic yards of medium (less tiles), 705. Distributor, Simplex Patent Mercury Seal four-armed type. ANTE A WORKS. During the year a new 25 feet diameter hopper bottom humus tank, and an open earth-sided concrete slab-lined secondary digestion tank were put into operation, and construction of three small primary digestion tanks with floating steel gas collectors was commenced. The gas will be used in a gas-fired water heater, which will provide hot water for circulating in coils in these digestion tanks to raise the temperature of the digesting sludge.