30 Conservation Department 



The Genesee river, during- tlie period investigated, summer of 

 1926, was found to be a comparatively small stream, so shallow, 

 except where ])onded by dams, and so abundantly supplied with 

 rapids and riffles throughout at least the U})])er two-thirds of its 

 length as to be unnavigable to even a small boat. The topography 

 of the region shows an elevation of about 1,500 feet above sea 

 level at Wellsville, compared with approximately 250 feet at Lake 

 Ontario. The intimate mixing of water and air resulting, affords 

 excellent o])portunity for replacing the oxygen which may have 

 been consumed, and it would necessitate extensive i)ollution indecl 

 to lower the content of dissolved oxygen to an alarming degree 

 under such conditions. The foam flecked ])ools bear witness of 

 the (Mitrainment of air, and the not infrequent values obtained 

 for dissolved oxygen, exceeding the saturation values at the exist- 

 ing tem])erature, most ])robably are due to conditions not in 

 equilibrium, and quite possibly indicate colloidal solutions of air 

 in water. 



Methods Employed, — Analytical methods ,em]^]oyed were in 

 genei-al those i-ecommended by the American Public Health Asso- 

 ciation, in "Standard Methods of Water Analysis," 6tli edition, 

 1925. in sections of the river of considerable depth, such as 

 north of and immediately south of Rochester, no attempt was made 

 to show the variation in oxygen content between the surface and 

 bed of the stream ; some data of this nature are available in Whip- 

 ))le's report of 1913.^ Rather it was attempted to get a repre- 

 sentative sample of the stream at each ])oint investigated, well 

 out into the flowing water, and uniformly well below the surface, 

 that all results might be com|)arable. In the shallower i^ortions 

 of the river, samples were taken as far distant as possible from the 

 last ])receding riffle in order to afford the water the greatest o])por- 

 1 unity to reach a condition of equilibrium. 



It is desii'ed to call attention to the obvious fact that in a sui'vey 

 covei-iiig a i-ivei- length of slightly less than 150 miles, and extend- 

 ing over a pei-iod of three months, the same water could not ))e 

 followed in its i)assage to the lake and analyzed at various ])oints 

 to determine just what ha|)])ens to it during its course. But even 

 such procedure, were it ))ossible. would have to be repeated at 

 successive intervals of time to secui'e data concerning average con- 

 ditions as well as fluctuations throughout the season. Conditions 

 are constantly changing; new industries are born and flourishing 

 manufacturing plants cease to exist; production rises to a maxi- 

 mum or (h-ops to a Tiiinimum, and with some the nature of the 

 |)roduct is changed. All have their effects u|)on the surroundings 

 directly connected with them. 



Conditions F£ncountered. — Data secured will be found in the 

 accompanying tables,- and in some cases grai)hical repres(Mitation 

 has been used in the hope that such would convex' moi-e readily 

 to the reader a pictni-e of conditions encountered. A |)roti!e 



K('|H.i< (.11 Hk. ScwaH,. |)i.|M,MiI System ..t Koclicstrr. N. V.. Kislicr. li»i:{. 

 Scf A|.i.('ii.ii\ III. 



