We can gauge the size of the water pollution 

 problem by considering the relation between the 

 amount of fresh water available in the Nation and 

 the amount needed to carry away its wastes. The 

 amount of fresh water that flows from the 

 continental United States and discharges into the 

 oceans does not vary its total much and averages 

 out at about 1,100 billion gallons a day. It is 

 estimated that in 1954 about 300 bilhon gallons of 

 the total avaOable supply of water were withdrawn 

 daily; of this amount, 190 billion gallons were 

 used to return wastes to the streams. It is further 

 estimated that at the end of this century, nearly 

 750 billion gallons of water will be needed to carry 

 away our population's wastes. At that time, the 

 Nation will be withdrawing a little more than 80 

 per cent of its total flow of fresh water, and will 

 be contaminating with polluted returns about 

 two-thirds of the total flow.^ The Ancient 

 Mariner's lament, "Water, water everywhere, but 

 not a drop to drink," could have greater relevance 

 to modern society than Samuel Coleridge could 

 ever have dreamt. 



Predictably, pollution and its effects are felt 

 most strongly and do the most damage in our 

 estuaries and Great Lakes. One reason is that 

 populations tend to cluster in these zones. An- 

 other is that these areas are the most valuable 

 portions of our marine environment and also the 

 most vulnerable to pollution. The hydrological and 

 geological characteristics of estuaries make these 

 waters a sink for the non-degrading wastes flowing 

 in the river basins. 



Of the world's 10 largest metropolitan areas, 7 

 have developed on major estuaries. Today, 70 per 

 cent of our Nation's population lives within one 

 hour's drive of an estuary, ocean or the Great 

 Lakes. Their personal and industrial wastes, 

 treated and untreated, pour into these waterways. 



Almost as important as the existence of water 

 itself within the coastal zone is the quality of the 

 water. Since the same water is often called upon to 

 serve more and more masters, plans for shared use 

 must be carefully laid, and compromises intro- 

 duced in order to permit desired competing uses to 

 coexist. For example, harbors and healthy oysters 

 can coexist if pollution levels are held down; 

 similarly, properly designed sewage treatment 



plants and a swimming area can coexist in the 

 same area. Water quality is the common denomi- 

 nator for the shared or multiple-use concept. 



M. TYPES OF POLLUTANTS 



To reduce the study of pollution, its causes and 

 effects to a manageable form, the National Acad- 

 emy of Sciences-National Research Council 

 broadly classifies pollutants entering watercourses 

 in eight categories:"* 



1) Domestic sewage and other oxygen-demanding 

 wastes. Ordinarily these wastes are reduced to 

 stable compounds through the action of aerobic 

 bacteria that require and obtain oxygen from the 

 water. At excessive residue levels, the resultant 

 oxygen reduction can have a serious impact on the 

 life in the water. The oxygen-demanding fraction 

 of domestic and industrial waste is growing much 

 more rapidly than the efficiency of waste treat- 

 ment, so that by 1980, it is estimated, the oxygen 

 demand of treated effluents will be great enough 

 to consume the entire oxygen content of a volume 

 of water equal to the dry-weather flow of all of 

 the United States ' 22 river basins. 



2) Infectious agents. Although modem disinfec- 

 tion techniques have greatly reduced the dangers 

 from disease-causing organisms in water, incom- 

 plete elimination of these agents from sewage and 

 domestic water supplies poses a continuing health 

 hazard. 



3) Plant nutrients. Growth of aquatic plant life is 

 directly related to the availability of mineral 



^Ibid. 



National Academy of Sciences-National Research 

 CoxxnoiX, Waste Management and Control, 1966, p. 12. 



Figure 2. Industrial wastes are a major source of 

 water pollution. Besides blocking recreation ac- 

 cess to the waterfront, obsolete industrial plants 

 contribute to the total pollution problem: water, 

 air, and land. (U.S. Coast Guard photo) 



III-50 



