116 



SEWER DESIGN 



capita. But he judged that, in view of the constantly increas- 

 ing demand for water for these purposes, and also considering 

 that an allowance of about 10 per cent should be made to cover 

 shortage on meter measurements, at least 35 gallons per capita 

 per day should be provided for these purposes. It is, of course, 

 understood that this is applicable only to Boston, and that the 

 amount will vary in different cities. Residential towns, for 

 example, require little beyond that needed for domestic use. 

 Other cities, with industries using large amounts of water, 

 may require more than 35 gallons adopted for Boston. Of 



TABLE XVI 



METERED WATER USED FOR TRADE AND MECHANICAL PUR- 

 POSES IN BOSTON, CHELSEA, SOMERVILLE, EVERETT, AND 

 CAMBRIDGE IN 1892 



course, the amount of water used in the various industries 

 of a city has no relation to the population, and should be 

 estimated from the amount and kind of manufacturing, 

 although it can afterwards be reduced to a per capita basis 

 for convenience. 



For public purposes Mr. Brackett has divided the use of 



