From the Thames above its tidal flow and above Teddington lock, million gallons were available, from the Lea all its flow except 5,400,000 gallons left for navigation and from the New River 2254 million gallons were pumped. Upward of 33,000,000 gallons were claimed from springs and wells. In 1900 Lon don consumed 226,000,000 gallons of water daily, which was distributed through 3,500 miles of pipes. The Thames, the Lea and the New mm 20 years ago were subject to pollution from the inflowing surface waters, and their filtered waters as well as waters obtained from wells contained from 15 to 100 bacteria per cubic centimeter. In 1902 an act was passed creating the Metropolis Water Board. It *as authorized to acquire the properties of the eight or more water companies above named and to enforce rigid regulations for the protection from pollution of the sources of London's water supply. Royal commissions investigated and reported on the purity of the supply, and out of the 294 exriments made by Dr. A. C. Houston in 1907 not a bacilha typhoeus was isolated, though millions of bacteria were dis covered, the Lea being most heavily laden with diem The Metropolitan Water Board was created by the act of 1907. That board took over the and facilities of the Metropolis Water The New Works Act of 1911, author ized the Metropolitan Water Board to construct large storage reservoirs at Staines, Laleham and Shepperton. New service reservoirs were constructed on Horseendon Hill, Greenford and on Barn Hill.
In January 1913 the Metropolitan Water Board, through the various intakes, drew daily from the Thames 132,859,184 gallons and from the Lea 55.300,700 gallons and from springs and wells 36,712,390 gallons and from ponds 313,600 gallons. The aggregate of that supply was 225X5,1174 gallons, which was at the rate of 33.44 gallons per person. New reservoirs are being constructed to provide additional waters and the daily consumption in 1918 was reported at 39 10 per capita for a total population of Parliament passed several acts for the conservancy of the waters of the Thames, Lea, New and other rivers and has empowered boards and commissions to take such action as may be necessary to protect the waters of said rivers from pollution by regulating the uses of their watersheds and otherwise by enforcing sanitary ordinances on the part of cities, towns and villages.
Most thorough and exhaustive investigations have been made in both London and Paris to ascertain the quality and the bacteria in the raw waters, which are the sources of supply for those cities and every precaution is taken to rid all such potable waters of their pathogenic species.
The official reports of Dr. A. C. Houston, director of the Metropolitan Water Board, over a series of years and of his skilled staff of experts at London are exhaustive.show
all phases of the water supply of in cluding its sources, amount, quality, bacteriolog ical and chemical tests, the processes for its purification, the results obtained, its distribu tion and all other conditions incidental thereto. In his official report for 1913 Dr. Houston said that `about eighty percent of the London Water Supply is derived from rivers polluted directly or indirectly with sewage, . . . that the three factors of sedimentation, devitalization and equalization are indeed of supreme importance in connectioq with the storage of impure water antecedent to its filtration. . . . The practice of occasionally 'dragging' or 'raking' the sur face of the filter beds to increase the yield of water or to prolong their working periods should be discontinued altogether, or only re sorted to under quite exceptional circumstances. . . . Over eight years' work on the London water question has convinced me that to a progressively increasing extent the Water Board are securing the reasonable if not absolute 'safety' of the Metropolitan Water Supply. This opinion will carry the more weight since 1 have Men, and still remain, a somewhat merci less critic of any imperfections in processes of water purification. . . . As a counsel of per fection. I still feel bound to advocate the choice of an initially pure source of water supply; but my own results and experiments do seem to indicate clearly that the evil effects even of an impure source can be largely, if not entirely, annulled by adequate storage and efficient filtra tion. . . In conclusion, my opinion is that the 'quality policy' of the Metropolitan Water Board should be directed towards securing an 'epidemiologically sterile' water (i.e., a water containing none of the microbes associated with waterborne epidemic disease) antecedent to fil tration by means of storage (sedimentation, devitalization and equalization) aided, if need be, by the occasional employment of supple mentary processes of water purification.) For the years 1906-13 the average number of microbes per cubic centimeter as reported by Dr. Houston in raw Thames water were 4,894, in the raw Lea water were 13.293 and in the raw New River water were 2,081.
He also reported that by the processes of subsidence and filtrations the number in raw Thames water was reduced from 5,250 to 16.1 per cubic centimeter, in raw Lea water from 9,363 to 30 9 per cubic centimeter and in the raw New River water from 2,172 to 14.1 per cubic centimeter. In all these cases the reduction was upward of 99 per cent. The filtered waters from Kent had but 7 microbes per cubic centi meter and there were in the Chelsea filtered supply only 7.3 microbes per cubic centimeter.