KUICHLING'S STATEMENT 131 



and three drops from each service pipe, including tap and curb cock, repre- 

 sents a fair measure of the average undiscoverable leakage in a well-con- 

 structed distributing system. As the size of a drop of water, however, 

 depends upon the form and magnitude of the surface from which it falls, 

 a number of experiments were made by the author to determine the weight 

 and volume of 100 drops falling from a cast-iron surface similar to that 

 of a pipe socket, from which it was found that one such drop per second is 

 equivalent to about 3 gallons per day. On this basis, and with the assump- 

 tion that on the average there are 504 pipe joints, 12 hydrants, 10 stop- 

 valves and 100 service pipes per mile of distributing pipe, the leakage 

 will amount to 2742 gallons per mile per day, or in round figures, say from 

 2500 to 3000 gallons per mile per day. Trans. Am. Soc. C.E., Vol. 

 XXXVIII, p. 18, 1897. 



Mr. Kuichling's results check closely those of Mr. Biackett 

 for a leakage of from 250x5 to 3000 gallons per day per mile of 

 pipe and correspond approximately with Mr. Brackett's allowance 

 for 6-inch pipe, and the average size of pipe in the distribution 

 system referred to by Mr. Kuichling was probably not far from 

 this size. 



Mr. Charles F. Loweth, an engineer of St. Paul, in discus- 

 sing Mr. Kuichling's paper, stated: 



The estimate in the paper (Kuichling's) of from 2500 to 30x30 gallons of 

 leakage per day per mile of pipe, in a well-constructed distribution system, 

 he believes is excessive. As a result of testing several new pipe systems, 

 in most cases before any service connections were made, the writer has come 

 to the conclusion that the leakage can be kept within 60 to 80 gallons per 

 inch mile of pipe per twenty-four hours, or 600 to 800 gallons per mile of 

 lo-inch pipe line per day. 



For several years past he has specified a leakage test for all new pipe 

 systems or extensions. The permissible leakage has been limited to from 60 

 to 80 gallons per day for each inch-mile of pipe, depending upon the pres- 

 sure, and inclusive of hydrants and valves, and a liquidated damage clause 

 added to cover any excess leakage over this amount. His observation has 

 been that honest and experienced workmen can readily keep the leakage 

 within this limit, especially when warned beforehand that their work will 

 be tested. A comparatively small amount of negligence, however, will 

 result in a considerable excessive leakage. Trans. Am. Soc. C.E., Vol. 

 XXXVIII, p. 30, 1897. 



In closing the discussion Mr. Kuichling stated in regard 

 to this: 



