WATERWORKS 



0222 



WATERWORKS 



When the full buckets reach the bottom, the 

 water flows out ; the ascending buckets are thus 

 empty, while those descending are filled. 



Undershot Wheel. This is a water wheel so 

 set up that the current of flowing water strikes 

 against the buckets, or paddles, of the wheel at 

 the bottom. This wheel uses only the momen- 

 tum of the flowing water, and its efficiency is so 

 low that it has been but little used. 



Both of these types have been replaced by the 

 turbine, and they are seldom seen. See WATER 

 POWER. 



WATERWORKS, the system of reservoirs, 

 pumps and mains constructed to supply com- 

 munities with water for domestic use, manu- 

 facturing, fire protection, etc. The chief matter 

 to consider in supplying water is the purity of 

 the source, since contaminated water spreads 



tration of the gravitation system. A huge 

 aqueduct of concrete will tap a series of reser- 

 voirs in the Catskill Mountains, so much above 

 the level of the city that the water will mount 

 to the twentieth story without pumping. In 

 Chicago, on the contrary, the water is driven 

 by pumps. It is drawn through tunnels from 

 far out in Lake Michigan (two or four miles), 

 and is forced through the mains by twelve 

 pumping stations. Such cities as rely on gravi- 

 tation, however, often supplement it with a 

 pumping system in order to supply the pressure 



PRIVATELY-OWNED WATERWORKS 

 The windmill is the pumping station ; the farmer easily provides a standpipe sufficiently high to 



force a stream of water into house and barn. 



disease. If water is not free from dangerous 

 impurities, especially such as are deposited by 

 sewage, it must be filtered or treated chemi- 

 cally. Large cities situated near rivers or large 

 lakes usually draw upon them for their water 

 supply, while small communities removed from 

 such facilities rely on wells, tapping under- 

 ground water. When water is taken from riv- 

 ers or lakes it may be pumped directly through 

 conduits and mains to the consumer or stored 

 in reservoirs and distributed at need. When 

 the source of supply is wells, the water is usu- 

 ally pumped into reservoirs of masonry, or 

 wrought-iron or steel standpipes, set on ma- 

 sonry foundations. 



Water is forced through the main either by 

 gravitation, the source being higher than the 

 place of distribution, or by pumping. The 

 new water system of New York is a good illus- 



required for fighting fires. In the district 

 topped by its lofty "skyscrapers," New York 

 maintains a separate system, the water being 

 driven through the mains under great pressure 

 from pumps. 



From the source of supply water is conveyed 

 by means of conduits, mains and numerous 

 radiating branches of diminishing diameter to 

 the consumer. The mains are of cast iron or 

 steel and have a diameter of from four to 

 forty-eight inches, occasionally more. The 

 mileage of water pipes in great cities is natu- 

 rally very large ; Chicago, for example, has 2,750 

 miles of pipes almost enough to stretch from 

 New York to Spokane. 



The consumption of water per person in 

 American cities is vastly greater than in those 

 of Europe; from 200 to 250 gallons a day 'for 

 each person is not uncommon. This large con- 



