FOREWORD 



The value of water that can be put to beneficial use in southern 

 California is so great that it seems advisable to call attention to existing 

 wastage along streams and in other wet-surfaced areas of that region. 

 Studies that have been made recently lead to the conclusion that the 

 possibility of utilizing such sources of supply to advantage is worthy 

 of the most serious consideration. This bulletin gives basic data which 

 may be applied in evaluating water now wasted that might be put to 

 profitable uses. 



The bulletin is in two parts: Part I, a report of investigations 

 made by the Division of Irrigation, Bureau of Agricultural Engineer- 

 ing, U. S. Department of Agriculture, dealing with the disposal of 

 water by evaporation and transpiration in various parts of southern 

 California, and Part II, a report of investigations made by the Water 

 Resources Branch, Geological Survey, U. S. Department of the Interior, 

 dealing with loss of water from Santa Ana River in lower Santa Ana 

 Canyon. Both reports were made cooperatively with the Division of 

 Water Resources, Department of Public Works, State of California. 

 It is believed that the publication of these two reports will throw needed 

 light upon the little-understood subject of waste of water through 

 natural causes. 



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