Studies of Distribution System Capacity in Seven Cities

Abstract

This article begins with a brief overview of the various causes of reduced carrying capacity in a water distribution system. The effect of all these causes of reduced carrying capacity is measured by determining the coefficient of capacity, C, in the Hazen‐Williams formula. The article presents a head loss test procedure for determining C, and provides the results of some of these head loss tests that were made for the water distribution systems of seven of the larger mid‐central United States cities. In most of these cities, tests have been made at varying intervals throughout the years, and here the C values plotted against the age of the pipe at the time of the test have been synthesized into trend curves.