SUMMARY 



The shore waters of Lake Erie have been shown to 

 be polluted by wastes from several harbors and creeks 

 or rivers east from S andusky, Ohio. These sources are: 



Rivers, in addition to the harm done to their 

 waters by wastes, have been spoiled for fish life by 

 the deposition of sludges which undergo slow decom- 

 position. Harbors and shores have been spoiled in like 

 manner. 



1. Buffalo Harbor by Buffalo and Lackawanna 



2. Station 9 from Cattaraugus Creek and Silver Creek 



3. Dunkirk Harbor by Dunkirk 



4. Erie Harbor by Erie 



5. Ashtabula River and Harbor by Ashtabula 



6. Station 38 from Grand River by Fairport and Paines- 

 ville 



7. Cuyahoga River and Cleveland Harbor by Cleveland 

 and Akron 



8. Sandusky Harbor by Sandusky. 



Out of this number, critical conditions were found 

 only in Erie Harbor, Ashtabula River, Cuyahoga River, 

 and Cleveland Harbor. The potentiality for critical 

 conditions must be assumed for Buffalo Harbor, Dunkirk 

 Harbor, and Sandusky Harbor. 



At several other points, which were not closely in- 

 vestigated or not investigated at all, pollution may be 

 found. These are: Port Colborne, Conneaut, and the 

 Black, Huron, Vermilion, and Sandusky rivers. 



In all cases except two, where undesirable con- 

 ditions were found, these conditions were so modified 

 by the diluting action of the lake water that no harm 

 to aquatic life could have resulted at the distance of 

 a mile directly out in the lake. The two exceptions 

 were found at Fairport and Toledo. At Fairport the 

 effect of wastes was detectable at a distance of 3 1/2 

 miles and at Toledo at a distance of 5 miles. How- 

 ever, in both of these cases conditions were nearly 

 normal at the distances given. 



The effect of polluting matter is more of a shore 

 effect than an offshore one. Because of this the in- 

 fluence of pollution at Buffalo, Erie, and Cleveland 

 is extended over a large area without getting far out 

 into the lake in a harmful form. 



Chemicals introduced with wastes can be safely 

 considered as sufficiently dispersed, when normal con- 

 ditions are restored in the water, and theii influence 

 is not spread over a much greater area than is the de- 

 tectable pollution. 



Spawning beds more than 2 miles offshore would 

 not be affected by pollution unless heavy charges of 

 wastes were added to the lake by nearby cities. The 

 number of such sources is so low that very few spawn- 

 ing grounds in the lake proper have probably been in- 

 fluenced by pollution. 



CONCLUSION 



The results of this study justify the conclusion that 

 pollution is not a factor in the decline of the fishes of 

 Lake Erie. The diluting action of the lake is so great 

 that detectable evidence of waste was not found at a 

 distance greater than a mile from shore, except in two 

 cases. However, this does not mean that pollution has 

 had no action on the fish population of the lake. Its 

 effect has lain in the killing of the fish formerly found 

 in rivers and harbors now polluted, and in the effect, 

 slight at most, on the spawning beds in the lake itself. 



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