206 REPORT OF THE COMMISSIONER OF FISHERIES. 
River. Also, since Providence and Pawtucket are manufacturing 
centers, a large amount of waste from gold and silver refineries, from 
bleacheries and dye houses, and coal tar products from the gas com- 
panies’ plants, ultimately 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 during each season, and at a time when few 
oysters are dredged for market. 
The section of the river which receives this large amount of sewage 
is a strip of water a little over 5 miles long, varying from about 1 mile 
to 14 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 twice in every twenty-four hours 
clean sea water from the bay below flows toward the polluted areas, 
and is a very important factor in the purification of the river. 
Much 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 by sewage, and because 
most of the oyster ground of Rhode Island waters is located in this 
body of water. The pollution of the Warren River is of only local 
importance, since it is soon swallowed 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 froma few private drains that discharge into the 
river. . 
The sewage of Fall River is the third factor in the pollution of the 
bay. This waste is discharged into the Taunton River near the head 
of Mount Hope Bay. The outfall of this sewer is, of course, at a con- 
siderable distance from the Providence River and Narragansett Bay, 
and even though a large quantity of sewage and mill waste is passed 
into the Taunton River, all visible evidence of pollution has disappeared 
from the water at the entrance of Mount Hope Bay, 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 which 
contamination can be spread to the oyster beds of the river and bay. 
The sewage from Newport never reaches the oyster beds, the nearest 
of which are at least 12 miles above Newport Harbor. 
