166 



Marine-oriented research and educational activities on the Nar- 

 ragansett Bay area have little conflict with other uses of the bay. 

 They exact no particular social costs in the form of unfavorable effects 

 on the bay environment and are income producing. Areas of greatest 

 economic impact are under supervision of the Military Establishment 

 and are subject to the changing dictates of national military policies. 



Waste disposal 



It is estimated that approximately 150 million gallons per day 

 (m.g.d.) of liquid wastes flow into Narragansett Bay through munic- 

 ipal sewer systems or treatment plants. At the beginning of 1969, 20 

 percent of these wastes received primary treatment, 70 percent received 

 secondary, and 1 percent received tertiary treatment. The remaining 

 undetermined amount of wastes are either discharged untreated into 

 the bay or to individual treatment systems such as septic tanks where 

 the effluent may eventually seep or leak into the bay. 



The tidal action in the bay and the bay itself are in fact part of the 

 waste disposal process. With two exceptions — harvesting of shellfish 

 and to a lesser degree contact recreation — this use of the bay for waste 

 assimilation is compatible with other uses at the existing levels of 

 waste treatment. 



The capability of the bay to assimilate waste products is a valuable 

 economic asset. Its worth can be estimated either in terms of the in- 

 creased value of the system for other uses or in terms of increased 

 costs for waste treatment if the bay could not be used for this purpose. 



The only real economic damage to bay resources by waste disposal 

 is the prohibition of shellfish harvesting in certain areas. This is a 

 damage to the commercial shellfish industry rather than to the shellfish 

 themselves since the closures are a matter of public health considera- 

 tions and not habitat damage. If the areas presently barred to com- 

 mercial shellfishing were opened, the value of the current commercial 

 crop might increase by as much as $1 million, assuming that there is 

 this much additional economic demand for the product. 



If the bay could not be used for disposal of partly treated wastes it 

 would be necessary to dispose of them to the ocean or else provide 

 advanced waste treatment. Based on the alternative costs of these two 

 disposal methods, the waste assimilation capacity of Narragansett 

 Bay has an annual economic value of $6 to $8 million. 



Total economic value of Narragansett Bay 



Table IV.3.16 summarizes annual economic activity caused by 

 Narragansett Bay, R.L 



The accounting is incomplete in the sense that no attempt has been 

 made to include imputed "values" or expenditures per user-days for 

 various recreational activities, notably swimming, hunting, skindiving, 

 and spearfishing. The expenditures incurred in these activities were not 

 included, for in none of the four cases were not included, for in none 

 of the four cases were both expenditures per participant and the num- 

 bers of participants known. Also it was not possible to derive adequate 

 estimates of the value the bay contributes to the people of Rhode Island 

 through its effect on environmental quality. This includes air tempera- 

 ture modification, open scenic space, and open space for low land air- 

 craft approach and take off. These features, which have been omitted 

 from the calculations, are unquestionably very valuable. 



