275 



TABLE IV.5.12.— ECOLOGICAL DAMAGE IN THE ESTUARINE ZONE' 



'Data from Reference IV.5.10. 



Section 4. Examples of Estuarine Systems Damaged by Pollution 



Even though water quality damage and ecological damage are dif- 

 ficult to quantify in terms of exactly how much damage has been 

 done and what was its cause, many estuarine systems have felt the 

 deleterious impact of human exploitation. Examples showing the im- 

 pact of one particular source of pollution or of one kind of pollutant 

 are rare, because use of the estuarine resource is seldom confined to a 

 single type of activity. The estuarine systems discussed here were 

 chosen because one particular kind of poUutional situation or effect 

 seems to dominate the environment ; but, nevertheless many other con- 

 ditions contribute to the total environmental damage in each case. 



municipal wastes 

 Raritmi Bay 



Raritan Bay between New York and New Jersey is a prime example 

 of a polluted estuary surrounded by an intensively developed area 

 (figure IV.5.27). The Raritan system, which is composed of the bay 

 itself, the Raritan River, the Arthur Kill, and the Narrows receives 

 approximately 1,500 million gallons of wastes per day which contain 

 over 1,300,006 pounds of BOD. Although 75 percent of the waste 

 volume is from industry, the major impact on the estuary is from the 

 nutrient and bacteriological content of the municipal sewage. The 

 densities of bacteriological indicator organisms along the shorelines 

 of the bay and in the confluences of the tributary systems indicate 

 gross contamination with human wastes, and the nutrient materials 

 contributed by municipal sewage systems have been sufficient to upset 

 the ecological balance in the system. 



In some portions of Arthur Kill and the Raritan River dissolved 

 oxygen values reach zero in summer conditions, and the western part 

 of Raritan Bay also has depleted dissolved oxygen. High photo- 

 synthetic production by algae counteract these effects in the larger part 

 of the bay itself. 



Coliform bacteria counts are high throughout much of the bay and 

 have forced the closing of some public bathing beaches; dye tracer 

 studies showed that unchlorinated human waste discharges from the 

 upper bay (New York Harbor) reached beaches on Staten Island 



