J909.] FRESH-WATER FAUNA IN PENNSYLVANIA. 103 



time these creeks are in splendid condition at many points, and this 

 is preeminently the case, as regards the fish fauna, in Neshannock 

 Creek. 



4. The Monongahela Drainage. 



We may say that of the Monongahela drainage by far the great- 

 est part is utterly polluted, chiefly by mine water.^ The Monon- 

 gahela and its chief tributary, the Youghiogheny, drain the most 

 important coal regions of the state, and there are, in this whole 

 region, only a few streams left which have clear water. They are 

 the following: Ten Mile Creek and Dunkard Creek in Washington 

 and Greene Counties, yet the South Branch of Ten Mile Creek 

 became polluted in the spring of 1908 by the bursting of an oil pipe- 

 line near Waynesburg, Greene County. Dunkard Creek is yet 

 splendid in every respect. Cheat River is clear, but there are only 

 two or three miles of it in the state, and on its right banks, at Cheat 

 Haven, a small run empties into it, which brings a great amount of 

 mine water from the coke-ovens at Atchinson, killing everything 

 along its right banks.^ 



The Youghiogheny is in a fair condition above Connelsville, 

 Fayette County, and Indian Creek, one of its tributaries, is very 

 good (trout stream). However, the Youghiogheny has improved 

 from Confluence down. For at this place it receives a badly pol- 

 luted tributary, Casselman River, which brings mine water from the 

 mines in southern Somerset County. The Youghiogheny above Con- 

 fluence, south into Maryland, is very clear and pure. 



For the rest, all the more important creeks tributary to the 

 Monongahela system, in Washington, Fayette and Westmoreland 

 Counties, are polluted by mine water. This is especially true in the 

 cases of George and Redstone Creeks, draining the Uniontown dis- 

 trict, Jacobs Creek, coming from the Mount Pleasant and Scottdale 

 mines, and, worst of all. Turtle Creek, with its tributary, Brush 

 Creek, which drain the coal fields of Westmoreland County. 



" Leighton, ihid., p. 126 ff. This condition obtained already in 1898, see 

 Rhoads, S. N., in Nautilus, 12, 1899, p. 133. 



" The condition of the Cheat below Parsons, Tucker Co., W. Va., is 

 dreadful, it being polluted by the refuse from a wood pulp mill. But it 

 improves farther down. 



