IRRIGATION PRACTICE AND HIGHWAYS 319 



sible at all, is not permanently profitable without 

 more moisture than the normal rainfall supplies; 

 and even in the remaining 35 per cent, possibly ex- 

 cepting the narrow coastal areas of the most north- 

 erly counties, irrigation is distinctly a needed ad- 

 vantage. Only about 4,000,000 are now irrigated 

 mostly from unstored stream-flow and underground 

 sources. About 2,000,000 acre-feet of water-storage 

 has been developed. Over 10,000,000 acre-feet ad- 

 ditional storage capacity is known to exist where 

 water is presumably available to fill it. The whole 

 state is becoming increasingly conscious that only 

 by the storage of flood waters now going to waste 

 and the more economical use of irrigation water, can 

 California fully achieve her agricultural heritage." 

 California irrigation undertakings were originally 

 predominantly proprietary and the product of indi- 

 vidual or corporate enterprise. Of those classed as 

 cooperative, very few of the older ones were or- 

 ganized that way except in a progressive policy which 

 attached shares of water stock to the land and finally 

 constituted water users as water owners and sharers 

 in management. The relation of public and com- 

 munity control to proprietary interests as it existed 

 when the United States Census was taken in 1910, 

 and in 1920 is shown in this way: 



1920 1919 Percentage 



of Increase 

 Individual and partnership 1,502,870 961,136 56.4 



Cooperative 1,215,696 779,020 56.1 



Irrigation districts 577,168 173,793 232.1 



Commercial 873,499 746,265 17.0 



