HYDROLOGY OF NEW YORK 



439 



water that will occur along the lower reaches of a river when 

 the stages at points higher up are known. Judgment as to such 

 cases is based upon the observed hight in previous years. 

 Hence, the value of a record of water stages in determining the 

 relation between the wave crest at various points along a river; 

 but the relation between these will not be identically the same 

 in all cases— it will depend upon* the distribution of the rain- 

 fall and other causes over the catchment basin of a river. The 

 average of a great many cases gives a result which, though some- 

 times in error, is in most cases nearly right. 



Predictions as to the hight of floods based on the preceding 

 general method have been kept in France since 1854, and in the 

 United States on the Mississippi, Missouri, Ohio and other tribu- 

 taries of the Mississippi for the last fifteen to twenty years. 

 Generally the rivers of New York State are not long enough 

 to make such predictions specially reliable, although on some 

 of the longer rivers they may be successfully a.pplied. At Cin- 

 cinnati, Louisville and Cairo predictions may be made from two 

 to six days in advance of a destructive flood. 



This matter is merely mentioned here as one of the practical 

 outcomes of the study of floods in large streams. It is exten- 

 sively discussed in Russell's Meteorology 1 to which the reader 

 is referred for more extended information. 2 



Maximum Flow of Streams in New York 



We will now take up a brief description of floods on the various 

 livers of the State, following the same order as previously used 

 in discussing the classification of streams. Since there is no 

 information as to floods on many streams, only those will be men- 

 tioned where information is available. 



Floods in Buffalo river. This stream is formed by the junction 

 of Cayuga creek. Buffalo creek and Cazenovia creek, which unite 

 near Buffalo. The catchment areas of these various streams are 

 given on page 205. The slope of Cazenovia creek is steeper in its 



'See chap. 10, River Stage Predictions, in Meteorology, Weather and 

 Methods of Forecasting and River Flood Predictions in the United States, 

 by Thomas Russell. A general resume of the cause of floods is also given 

 in chap. 9 of the same work. 



'Abstract from Report of the Water Storage Commission. 



