120 



SEWER DESIGN 



Water Consumption per Head per 

 Day In (Juliana 



waste from a water sys- 

 tem is to measure the 

 night flow and assume 

 that all that amount ex- 

 ceeding a small quantity 

 for night use and un- 

 avoidable or incurable 

 waste is a constant waste 

 that can be cured if proper 

 measures are adopted. 

 Thus Mr. Freeman in his 

 report to Hon. Bird S. 

 Coler on the water-supply 

 of New York determined 

 the rate of flow from hour 

 to hour, as shown in Fig. 

 27,* and showed graph- 

 ically what a large part 

 of the city's water-supply 

 served no purpose, but 

 was altogether wasted. 

 In figures, his conclusion 

 was that at the times 

 when the demands for 

 water were practically 

 zero, that is, between 2 

 and 4 in the morning, the 

 consumption still existed 

 at the rate of 94 gallons 

 per head per day. Mak- 

 ing the liberal allowance 

 of 19 gallons for night use 

 and 10 gallons for incur- 

 able waste, Mr. Freeman 



* Redrawn from Diagrams 

 Nos. 5 and 6. 



