114 Conservation Department 



Below the Federal lock and sheltered from the river's current 

 even greater depletion was observed. A short distance below, a 

 great sewer bursts into the river through the old canal wall, and 

 less tlian a mile farther a virulent and odorous textile effluent adds 

 its quota. Results of determinations at these points are listed in 

 Series II, and the serrated portion of the graph (Fig. 2) illus- 

 trates their intensity. But the assimilative capacity of Niagara 

 with its normal flow of more than 200,000 cubic feet per second 

 is enormous, and the mighty current rushes with its cargo to the 

 falls and rapids below, there to be subjected to unparalleled oppor- 

 tunity for aeration and assimilation. Eddy currents soon dissipate 

 the virulence of pollution at any point, though the near shore 

 curve shows a steady decline to the foot of Grand island : the water 

 in the channel however is not appreciably affected. And finally 

 the water reaches the comparatively quiet level past Lew^iston and 

 Youngstown to Lake Ontario, with oxygen content far beyond 

 its normal saturation capacity. 



Other Streams. — It has been emphasized in the past reports 

 that data can give a picture of conditions only at the time of 

 observation, and that one may judge through experience what 

 results are liable to be misleading, and formulate conclusions 

 accordingly. As an instance, Cayuga creek was analyzed above 

 and below pollution entrance from Lancaster on two separate 

 occasions more than two months apart. As listed in Series III, 

 where pollution at the earlier date had been indicated by a reduc- 

 tion of dissolved oxygen to 85 per cent of saturation and presence 

 of 2.4 parts per million of free carbon dioxide, the later examin- 

 ation revealed an oxygen reduction to 23 per cent and carbon 

 dioxide content of 12.1. Farther downstream the comparable 

 oxygen figures w^ere 98 and 7. Cayuga creek is thus practically 

 ruined for fish life below Lancaster andDepew. 



Ellicott creek is polluted by creamery wastes at Bowmansville, 

 and the effects though not very serious are detectable for a couple 

 of miles. 



Pollution to Lime lake outlet by milk wastes is considerable, 

 and a promising trout stream thereby endangered. 



The evidence would indicate that Elton creek is not seriously 

 affected by dairy wastes at Delevan. Potential possibilities must 

 not be disregarded. 



Spring brook receives cannery wastes just above the pond into 

 which a part of Springville sewers. The pollution, while probably 

 not fatal to at least the hardier forms of fish, ])roduces a most 

 undesirable condition in tlie pond, detached patches of blue-green 

 algae flecking its surface. 



Effect of the milk shipping station at East Otto upon South 

 Branch C'attaraugus was found to be inappreciable at time of 

 investigation. 



