Water Quality Yardsticks

Abstract

P E R I O D I C A L L Y the question those free, or at least relatively free, arises whether a new yardstick for of contamination. Although the test measuring the sanitary quality of wa-was applied to rural well supplies, emter is needed. The question is well phasis was placed upon the checking taken because it emphasizes the de-of municipal waters. As improvesirability of determining whether ments were made in methods of water changes in operation or standard of purification, the test was used comquality of finished water warrant paratively, to show differences in the changes in methods of evaluation. coliform numbers in raw and treated The mere fact that the question is pro-waters. pounded does not imply that changes Along with improved purification are imperative or even necessary. It procedures, refinements and simplifidoes mean, however, that the present cation of the coliform test have also status of measurements of sanitary wa-been .made. Although the coliform ter quality should be examined and group consists of two principal species, placed in perspective.Escherichia coli and Aerobacter aero-917