RUNNING WATER

Greymouth Evening Star, 27 September 1928, Page 9

RUNNING WATER

NOT ALWAYS FIT TO DRINK

Disastrous consequences face those vacationists and campers who still cling to the popular belief that “running water, if not always pure, will at least purify itself ixx a dozen miles Ol’ so.”

The United States Public Health Service issues a warning against this erroneous belief in a critical review of researches on this subject based on extensive experiments conducted in the laboratories devoted to a study of stream pollution, says the “San Francisco Chronicle.” “Water contaminated with organic matters found in sewage and in various industrial wastes,” says the report, does gradually rid itself of such pollution,, if allowed free access to air. Early studies of this self purification led to the abandonment of a theory based on the direct action of oxygen on the organic matters, and subsequent research has revealed that the self-purification of streams is essentially a biological process. In this sense, the oxygen contained in aerated or running water does not operate as a sterilising agent, as once believed, but rather as a neutralising or deodorising agent for some of the gases resulting from the bacterial decomposition of the organic matters. “While thus relegated to a secondary role, the amount and rate of disappearance of the oxygen which is contained in a given water nevertheless serves as an excellent indicator, first of fish life and, with increasing pollution, as a warning of impending nuisance conditions. With the understanding that a bacteriological examination is a much better index of wholesomeness or fitness for drinking I purposes, it has accordingly become customary to express the pollution of a given water in terms of its demand for dissolved oxygen when reference is made to the threatened approach of nuisance conditions.”