AVAILABLE AND DEVELOPED WATER POWERS 



17 



AVAILABLE AND DEVELOPED WATER POWERS IN UNITED STATES 



The surveys and examinations necessary to a thorough and 

 ccurate report of the water-power resources of the United States 

 have never been completed. While in certain parts of the coun- 

 try they are fairly well known, in other parts, however, the infor- 

 mation is very fragmentary, and, therefore, an estimate of the 

 available water powers, such as given in Table III, must neces- 

 sarily be considered approximate. 



TABLE III 

 ESTIMATED AVAILABLE WATER POWER IN UNITED STATES 



These values are based on estimates prepared by the United 

 States Geological Survey for the National Conservation Com- 

 mission, 1908. With some revision, owing to lack of data avail- 

 able at that time, these estimates would place the minimum water 

 power of the country at approximately 31 million horse-power 

 and the maximum at 56 millions. 



In arriving at this minimum horse-power, the minimum flow for 

 the two lowest seven-day periods in each year for seven years was 



