206 EEPORT OF THE COMMISSIONER OF FISHERIES. 



River. Also, since Providence and Pawtucket are manufacturing 

 centers, a large amount of Avaste from gold and silver refineries, from 

 bleacheries and dje houses, and coal tar products from the gas com- 

 panies' plants, ultimatel}^ find their way into the river. 



In addition to these more important sources of pollution, the drains 

 from numerous shore resorts and summer residences situated on the 

 river banks must be named as a secondary source of contamination. 

 These drains are of minor importance in the general contamination of 

 the water, since the amount of sewage discharged by them is small in 

 comparison with that already mentioned, and also because they are in 

 use but a few months dui'ing each season, and at a time when few 

 oysters are dredged for market. 



Tlie section of the river which receives this large amount of sewage 

 is a strip of water a little over 5 miles long, varj^ing from about 1 mile 

 to 1^ miles in width. As has already been pointed out, the tide 

 reaches well up into the river past Providence and up the Seekonk 

 River nearly to Pawtucket. Thus tAvice in ever}- twenty-four hours 

 clean sea water from the bay Ijelow flows toward the polluted areas, 

 and is a very important factor in the purification of the river. 



IMuch more space has been devoted to the description of the con- 

 ditions in the Providence River than will be given to the other waters 

 of the bay, because this river is more polluted b}' sewage, and because 

 most of the oj'ster ground of Rhode Island waters is located in this 

 bod}^ of water. The pollution of the Warren River is of only local 

 importance, since it is soon SAvallowed up in the large volume of fresh 

 sea water it encounters when this stream joins the Providence River. 

 The contamination of the "Warren River is due chiefly to mill waste 

 and to the sewage from a few private drains that discharge into the 

 river. 



The sewage of Fall River is the third factor in the pollution of the 

 bay. This Avaste is discharged into the Taunton River near the head 

 of Mount Hope ^aj. The outfall of this sewer is, of course, at a con- 

 siderable distance from the Providence River and Nafragansett Bay, 

 and even though a large quantity of sewage and mill Avaste is passed 

 into the Taunton River, all visible evidence of pollution has disappeared 

 from the water at the entrance of Mount Hope Ba}', nearly 7 miles 

 distant from the sewer outfalls. 



These three sources, then — the Providence sewers, the Warren mill 

 waste, and the Fall River sewers — are the principal ones from AA^hich 

 contamination can be spread to the 03^ster beds of the river and bay. 

 The sewage from NeAvport ncA^er reaches the oyster beds, the nearest 

 of which are at least 12 miles abo\ e NcAvport Harbor. 



