WEST VIRGINIA GEOLOGICAL SURVEY. 



23 



compilation of results shows a very disquieting state of affairs 

 in West Virginia. Floods in the Ohio at "Wheeling have increased 

 28 per cent in number in 26 years; Potomac floods at Harpers 

 Ferry have increased 36 per cent in 18 years ; the Monongahela 

 floods, at Greensboro, Pennsylvania, show an increase of 73 per 

 cent in 24 years; and at Charleston an increase of 83 per cent 

 is shown by the Kanawha in 20 years. 



"The increase in low water periods, for the same time, fol- 

 lows: Ohio river 39 per cent; Potomac 40 per cent; Mononga- 

 hela 36 per cent ; and Kanawha about the same as the Mononga- 

 hela. 



"The actual quantity of water discharged by the Potomac 

 per year is 8 per cent more than 12 years ago; and for the Ohio 

 at Wheeling, the quantit}^ is 13 per cent greater. 



"The average rainfall for the whole state of AYest Virginia 

 seems to be about 2^ per cent less than it v/as 8 years ago. This 

 does not necessarily imply that the decrease will be permanent 

 or that it will continue. It is well known that rainfall varies 

 greatly. It sometimes increases during a term of years, then 

 declines, and again increases. The cycle of change -seems to be 

 'about 35 years ; but that matter needs additional proof before 

 it should be accepted as settled. 



"The increase of the total discharge of West Virginia 

 rivers, in spite of diminishing rainfall and a greater fluctuation 

 than formerly in the periods of high and low water, is due solely, 

 so far as available data can be interpreted^ to the deforestation 

 of the mountains. There is no reason to doubt that a continua- 

 tion of the timber cutting and burning will increase the fluctua- 

 tion of the streams, if, indeed, it does not permanently reduce 

 the rainfall which is b}^ no m.eans improbable. 



"Water Resources," 



"The average annual rainfall in West Virginia, including 

 melted snow, is about 40 inches. The amount is 2,322,295.810,000 

 cubic feet, enough to fill a reservoir of 16 square miles and one 

 mile deep. The mass of water is disposed of in two ways. Part 

 of it flows away by the rivers, and part of it evaporates before 

 it reaches the large watercourses. The part which goes out by 



