THE EFFECT OF LOAD FACTOR 169 



the capacity of the plant that a sufficient reserve capacity is 

 no longer available, it becomes necessary to build additions, 

 and in that event, the additions are needed to take care of the 

 added quantities of water that are drawn. 



If the particular time in the course of development when 

 new works are required is taken for especial consideration, it 

 is then found that the additional quantity of water drawn rep- 

 resents a great increase in capital outlay needed to secure it. 



In the whole period of development two conditions are thus 

 presented: the first runs through some years when increased 

 capacity is not required to furnish an additional quantity of 

 water; and the second begins and covers the period when addi- 

 tional capacity and investment are required to furnish perhaps 

 a rather moderate increase in output. 



Taking both of these considerations into account, and aver- 

 aging the conditions right through, the additional quantity of 

 water, great or small, will cost about as much in proportion as 

 the main output. 



There may be reasons for temporarily adopting the other 

 classification, especially in the case of a new plant for which 

 business is being secured slowly and with difficulty. In the 

 normal water works operation, the writer believes that every 

 bit of the cost of production of. water, whether operating ex- 

 penses or capital charges, should be carried in the output cost. 



If this is always done, there remains to be separately ac- 

 counted for as output charge under this general procedure 

 only so much of the additional cost of the pipes and reservoirs 

 as is not chargeable to fire service. That will probably be rela- 

 tively small in amount and may logically be handled as part 

 of the service charge. That may be done so far at least as will 

 not increase the service charges above an amount that is other- 

 wise fair to the smallest takers. 



