Volume 2

A study of the pollution and natural purification of the Ohio river / Prepared by direction of the surgeon general.

  • United States. Public Health Service
Date:
1924-
Catalogue details

Licence: Public Domain Mark

Credit: A study of the pollution and natural purification of the Ohio river / Prepared by direction of the surgeon general. Source: Wellcome Collection.

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    and their present relation to public health; and the data collected are presented here with reference to their future and general rather ‘than their immediate and local significance. As to the more general purposes, they have been pursued in the hope rather than in the expectation of accomplishment, not in full but in sufficient measure to be useful. The factors concerned in the pollution and especially, perhaps, in the self-purification of a great river system are of extreme complexity; and in so far as they may be found to be related in any general and simple way this is to be considered as a fortunate rather than an anticipated circumstance. The study. has, therefore, been to a considerable extent experimental, designed to test the applica- bility of the methods applied to the ends in view. GENERAL STATUS OF POLLUTION IN THE OHIO RIVER The Ohio is one of the principal tributaries of the Mississippi River, and among the largest river systems of the United States. Conditions with respect to sewage pollution are essentially the same as those existing quite generally in the large inland streams of the country, except that the necessity for some measure of control appears to be rather more imminent than in any other stream of equal size. The main stream, measured from its junction with the Mississippi to the confluence of the Allegheny and Monongahela at Pittsburgh, is 960 miles in length; and from Pittsburgh to the headwaters of the Allegheny is a further distance of about 400 miles. The river drains an area of 203,000 square miles, with a population of 14,500,000, or about 71 inhabitants per square mile. Of this population approxi- mately 5,100,000 reside in cities of more than 2,500 inhabitants. Directly upon the main stream are cities and villages aggregating 2,400,000 in population, the largest units in this aggregate being the metropolitan districts of Pittsburgh (1,043,000) at the upper end; Cincinnati (564,000) midway between Pittsburgh and the mouth; and Louisville (286,000) 130 miles below Cincinnati. All the cities upon the watershed necessarily discharge their sewage into the river, either directly or through its tributaries. Except near the periphery of the watershed, where the streams are small, the immediate pollution resulting from the discharge of sewage is seldom grossly offensive, owing to the rather ample dilu- tion. Consequently the artificial treatment of sewage is almost negligible, entirely so along the main stream. The distances between cities are, moreover, generally so great that natural’ purification greatly reduces the pollution; and if it were:required merely to pre- vent gross pollution, offensive to the senses of sight and smell, the necessity for any general control of sewage pollution would be rather