SOUTH NORWOOD. 



HISTORY. 



Reference is made also to this farm by the Rivers 

 PoUation Commission, First Report, Vol. I., pages 

 85 to 87 (1870). 



About 30 acres of low-lying clay land with 

 sufficient slope for natural surface drainage have 

 been well laid out for irrigation. The drainage of 

 about 4,000 people is received into a subsidence tank 

 at the upper end. Periodical analyses extending 

 over a whole year (September 24, 1868, to September 

 24, 1869) were made, and I have worked out the 

 average for the effluents (see No. 2 below). Figures 

 are given of samples taken on February 25 and 

 March 12 and 25, 1869 (see Nos. 3 and 4 below). It 

 would appear that the " average composition of the 

 sewage " (see No. 1 below) is merely a i-epetition of 

 No. 3 sample figures. Judging from the chlorine 

 the average for the year should be much higher — on 

 July 15th the chlorine in the effluent was 13-10. 



in a stiff clay soil. The Dry-weather Flow is 600,000 

 gallons, and the Storm Flow has at times exceeded a 

 rate of 4,000,000 gallons in twenty-four hours. The 

 Water Supply is from wells sunk in the chalk. The 

 Rainfall is 24'04 in. per annum, and the Drainage 

 Area of districts sewered 1,200 acres. Flushing. — 

 There are large automatic tanks, tipping tanks, and 

 flushing vans and hose. The average Stay in 

 Sewers is one hour and the Distance under 1 mile. 

 Screens with 1-in. and j-in. spaces are provided 

 except to the 15-in. sewer. Pumps are employed to 

 raise the sewage 10 ft., 15 ft. or 24 ft. to the highest 

 portion of the farm (about 33 acres), which lies 

 considerably above the level of the outfall sewers. 

 The effluent from some of the land near the bottom 

 of the farm can, if necessary, be pumped up to the 

 highest land, a 15-in. underground pipe conveying 

 the partially treated effluents back to the pump 

 well. Settling Tariks. — The bulk of the sewage 



REPORTS TO THE ROYAL COMMISSION. 



Separate or Combined. — The 

 The Sewage, sewerage system is partially sepa- 

 rate, about two - thirds of the 

 streets having duplicate sewers for surface water 

 and for the rain from the front portions of roofs. 

 The streets are macadam or gravel. The sewage is 

 entirely Domestic. There is very little Subsoil Water, 

 as the sewers have been well constructed and are laid 



passes through two settling tanks, each 60 ft. by 

 12 ft. by 3 ft. 4 in. average depth, provided with 

 scum boards. Both are used together continuously, 

 and they are cleaned out once a week by means of 

 mechanical bucket elevators discharging into adjacent 

 sludge beds. The sewage from the 15-in. low-level 

 sewer fl.ows through a small tank, or catchpit, from 

 which the sludge is removed by hand each week. 

 The Stay in Tanks is from one to one and a half 



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