102 ORTMANN— THE DESTRUCTION OF [April 23. 



Connoquennessing Creek, flowing into the Beaver from the east, 

 is another badly polluted stream. In this case there are various 

 causes of pollution, but the chief one is the refuse from the glass 

 works at Butler, Butler County. In the lower parts of Connoquen- 

 nessing Creek traces of life are yet present, but in a few years every- 

 thing will be gone. Above Butler, the creek is in a fair condition. 

 Of its tributaries, Glade Rim is polluted by oil well products. Brush 

 Creek is good, and also Slipperyrock Creek in its lower course. 

 The latter is an example of the natural clearing of the water, for in 

 its upper parts, in northern Butler County, it is in a very bad con- 

 dition, polluted by mine water. In this case dilution of the pollution 

 apparently plays an important part, for at least two of its tributaries, 

 Wolf and Muddy Creeks, are in good condition. In Wolf Creek the 

 effect of plain sewage is distinctly seen by the fact that the fish- and 

 mussel-fauna are favored by it — the Unionidae attain an unusual size 

 just below the point where the sewage from Grove City, Mercer 

 County, goes into the cr.eek. 



Of the two rivers which form the Beaver, Mahoning River is, 

 as has been shown by Leighton,* badly polluted in the state of Ohio 

 at Alliance, Warren, Niles and Youngstown. Yet in Pennsylvania, 

 in its lower parts, it is rich in life. We again have to deal here with 

 the natural clearing process of the water. At Hillsville, where the 

 Mahoning enters our state, it is in poor condition, yet there is some 

 life. Then comes a dam at Edinburg, and below this dam condi- 

 tions are much better. In fact, the fauna is rich, and continues so 

 till the river joins the Shenango. In this case, there are no impor- 

 tant tributaries along this stretch, and the clearing of the water 

 cannot very well be attributed to dilution. 



The Shenango River above Newcastle is in good condition all 

 the way up to its sources, and so are its tributaries, Neshannock 

 Creek, Pymatuning Creek and Little Shenango River. Only at and 

 below Sharon and Sharpsville, in Mercer County, some pollution 

 goes into the Shenango from the steel mills, but it has not had much 

 effect yet. However, the damage is bound to increase, and I am 

 afraid in a few years the effect will be noticeable. At the present 



*See Leighton, M. O., U. S. Geol. Surv. Water Supply and Irrigation 

 Paper no. 79, 1903, p. 133. 



