Engineering Wonders of the World
Volume III

THE DRAINAGE SYSTEM OF LONDON. 221 At present the outfalls have a total dis- charging capacity for sewage and rain water of 1,000,000,000 gallons a day. In addition, pumping power has been provided for lifting 456,000,000 gallons a day of rain water from the storm overflows into the river The sewers under the control of the London County Council (of which Mr. Maurice Fitz- maurice, C.M.G., M.Inst.C.E., is chief en- gineer, Mr. J. E. Worth, M.Inst.C.E., district engineer, having charge of the district on the north side of the Thames, and Mr. R. M. Gloyne, M.Inst.C.E., of that south of the river), are: ,216 miles on the north side of the Thames and 129 miles on the south, making a total of 345 miles of main and intercepting sewers. It must be remem- bered that in addition to the above there are all the sewers, one in each street, which discharge into the main-line sewers These local sewers are under the control of the Borough Councils, and, although, small, are, of course, of considerable length, totalling in the aggregate about 2,000 miles. The men who work in the sewers are called “ flushers’’—though not much flushing, in the general acceptation of th© term, is le- quired where the flow is so The Sewer- considerable as that in the men s Duties. gounc-ps gewers. The prin- cipal duties of these men are to remove the large quantities of “ detritus ’’—sand, gravel, and macadam—which finds its way into the sewers through the surface gratings and street gullies. Many thousands of cubic yards are removed annually. This work is generally carried out during the night, and involves some difficulty and danger. The large flow of water in the sewers and the possibility of a sudden influx of storm water render the greatest precautions neces- sary. Life-lines are always Dangers. kept handy, and permanent safety-bars are built into the sewers, across which theyare placed when the men are at work. Other dangers arise from the discharge of hot water and steam, though by the General Powers Act of 1894 manufacturers are pro- hibited under penalties from releasing into the sewers anything of a temperature higher than 110 degrees Fahrenheit, or any chemical or manufacturing refuse that might involve risk of injury to the men. working underground. Again, there is the danger connected with the possible presence in the sewers of in- flammable gases and of the waste from in- flammable liquids. This risk, which has been considerably augmented by the great number of petrol-driven vehicles, is guarded against by the use of special safety lamps. Thanks to the elaborate precautions taken, accidents of a serious character are very few in number, and the health of th© men is generally good. During the summer months all the sewers are deodorized as much as possible by the addi- tion to the sewage of quantities of perman- ganate of potash, carbolic powder, and other disinfectants. The chief pumping stations for dealing with sewage and flood water are interesting on account of the vast volumes which, they have to lift. The western sta- tion, at Pimlico, on the north- ^’Jr”.pinS’ 1 Stations. ern low-level sewer, contains four single-acting beam engines of 90 horse- power each, with, steam cylinders of 37-inch diameter and 8-foot stroke. Each, engine operates two pumps. To provide for possible breakdowns, an auxiliary engine of 120 horse- power is kept in reserve. The whole installa- tion is able to lift 54,000,000 gallons of sewage a day 18 feet to the head of the second section of the sewer running to Abbey Mills. The latter pumping station, which covers about seven acres of ground, is a very handsome struc- ture both inside and outside. , . Abbey Mills. The engine-house has a cruci- form shape, each of the four arms housing two large beam engines, with beams parallel to one another. All the steam cylinders are