118 The City's Challenge in Resource Use 



tinguish them in clean-cut fashion from the general and nonurban- 

 ized. However, a number of urban requirements worth noting are 

 clearly visible here and now. Among these are the following: 



Water. Urban people, as people, do use more gallons of water per 

 capita for domestic uses than do rural people. However, the differ- 

 ence is not great, and seems to be connected primarily with the 

 standards and mechanics of cleanliness, though air conditioning and 

 other special functions are beginning to be important in some situ- 

 ations. In urban areas, water is used in considerable quantities both 

 for cleansing and for carrying the wastes of the city, as on a con- 

 veyor belt, to points of disposal. Moreover, the industrial uses of 

 water have grown dramatically. While some conspicuous expansions 

 are outside the urban areas, the water requirements of industry are 

 heavily concentrated within the metropolitan regions because of the 

 labor ties and market desires of modern industry. Industrialization 

 is, after all, largely an urban phenomenon both as to cause and 

 effect. The threatened water-shortage map of the United States coin- 

 cides almost perfectly with the pattern of maximum urbanized de- 

 velopment except, of course, in certain near-desert regions.- 



However, the water problem is not so much a problem of greater 

 consumption due to city standards as a problem of concentration 

 and delivery made necessary because the consumers are concen- 

 trated the way they are. This is the unique urban aspect of the water 

 problem. Early in the process of urban development the pattern of 

 settlement makes private wells and springs impossible, as well as 

 reliance on local rainfall; it may locate millions of people where the 

 "natural" local resources are totally inadequate. This gives us a pres- 

 sure on water resources over and above the pressure which would 

 have existed if the same number of people with the same total water 

 requirements had been distributed differently in a nonurban or widely 

 dispersed pattern. 



Water supply is thus a dramatic illustration of the "take-off prin- 

 ciple" which plays so important a role in urbanization. Just as an 

 airplane becomes suddenly air-borne after attaining a defined air 



2 Edward A. Ackerman and George O. G. Lof, Technology in American 

 Water Development (Baltimore: The Johns Hopkins Press, for Resources for 

 the Future, in press). 



