PROTECTION OF RIVER AND HARBOR WATERS FROM 

 MUNICIPAL WASTES 



WITH SPECIAL REFERENCE TO THE CONDITIONS IX NEW YORK 



THE PROBLEM OF SEWAGE DISPOSAL 



CITY life presents pressing and peculiar biological problems. When a 

 large number of human beings are concentrated upon a small area 

 the fundamental needs of individual life must be met by new means. 

 Special measures must be adopted for getting food from a wide radius 

 into the center where so much of it is to be consumed. The spread of epi- 

 demics which always threaten crowded communities must be guarded 

 against; and the waste products which accompany all living processes must 

 be removed. 



This last task, the removal of the city's wastes, is one of the most 

 difficult which confronts a modern municipality. From every large city 

 there pours out a river of waste material which pollutes streams, harbors 

 and foreshores, spoiling what should be the chief pleasure spots of the city 

 and damaging property values, if it does not actually threaten human life 

 and health. By the modern methods of sanitary science these liquid wastes 

 can be purified and rendered harmless and it is with such methods of pro- 

 tecting the purity of inland and seaboard waters that a section of the Public 

 Health Exhibit of the American Museum now deals. 



City sewage is a far less offensive substance than might be imagined. 

 To the sight it is simply a grayish liquid with fine fi < ! '" suspended matter 

 in it; to the smell it is inoffensive when fresh, having only a faint musty odor. 

 Analysis shows that the average American sewage contains less than one 

 part in a thousand of solid matter, the rest being water. Of the solid matter 

 half is of miner J nature, so that only a residuum of perhaps four-hundredths 

 of one per cent of organic matter requires especial treatment. It is the vast 

 volume of the sewage stream however, which makes the problem such a 

 serious one. For example, there is now discharged into New York harbor 

 about oOO million gallons of sewage a day. This amount of liquid if con- 

 centrated in one place, would fill East River under the Brooklyn Bridge 

 for a distance of one-fifth of a mile. Even four-hundredths of one per cent 



