It has been estimated that the irrigated and irrigable area under private canals is about 80,000 acres, and that that still undisposed of in 1909, irrigated by the state under the Carey Act, amounted to 180,000 acres.
Commanding an irrigable area of 130,000-150,000 acres,' and has a diversion dam (rock-fill type) 600 ft.
Of laterals; the larger Payette-Boise project in Ada, Canyon and Owyhee counties (372,000 acres irrigable; 300,000 now desert; 60% privately owned), whose principal features are the Payette dam (rock-fill), 100 ft.
The irrigable area of Wyoming is estimated at about 6,200,000 acres, lying chiefly in Bighorn, Sheridan and Johnson counties in the N.W.
The Irrigation Commission of 1901 advised an expenditure of 30 millions sterling, spread over a term of twenty years, and irrigating 62 million acres in addition to the 47 millions already irrigated at that time; but it was estimated that that programme would practically exhaust the irrigable land in India, and that some of the later works would be merely protective against the danger of famine, and would not be financially productive.