92 THE UNITED STATES GEOLOGICAL SURVEY. [bull. 227. 
begun at important points in the various States and Territories. 
Construction is in progress in Nevada and Arizona, and plans leading 
to early construction in several other States are in hand. For locations 
of the principal irrigation projects see fig. 2, p. 80. 
The States and Territories in which reclamation works may be built 
and which include public land from which a revenue is derived are 
Arizona, California, Colorado, Idaho, Kansas, Montana, Nebraska, 
Nevada, New Mexico, North Dakota, Oklahoma, Oregon, South 
Dakota, Utah, Washington, and Wyoming. 
The amount of available funds derived under the law from the 
different States differs widely, as the largest amount of land is being 
disposed of in those States where the climatic conditions favor farming 
without irrigation or where there are considerable bodies of timber 
land. Thus it happens that the States which have the largest amount 
of arid land and the development of which under irrigation is most 
important contribute the smallest amount to the fund. 
The works must be so designed as to reclaim arid land whose value 
will be so great that the cost of the water can be readily repaid by the 
settlers living on the land. The cost of the works is apportioned with 
a view to returning to the reclamation fund the cost of construction, 
and thus it is necessary not merely to conserve and regulate the flow 
of the streams, but to do this in such way that there can be no question 
as to the ability of the settlers to repay the cost to the Government. 
The money thus returned to the Treasury is added to the reclamation 
fund for subsequent use. Payments are made by the settlers in ten 
annual installments. 
The irrigation of arid lands has already advanced, through private 
enterprise, to a point where the easily available waters have been 
utilized. There remain large rivers and the erratic floods which must 
be controlled for the reclamation of tracts of land which are partly in 
public and partly in private ownership, but to which water can not be 
brought by ordinary effort. 
Nearty all the projects of reclamation involve not merely engineering 
difficulties, but legal and social questions dealing with acquired rights 
and with individuals having diverse views and conflicting interests. 
Thus it is necessary to employ not only engineering ability, but also 
a certain amount of legal skill, and, with these, tact and judgment in 
adjusting conflicting interests. 
The thorough study which is being made of the opportunities for 
reclamation of the arid West, especially for the construction of large, 
works of irrigation, will result in great changes in, and rapid develop- 
ment of the resources of, the western half of the United States. It 
will make available for use hundreds of thousands of acres of land now 
sterile and waste, and will indirectly result in giving increased value 
to all property, whether directly connected with agriculture and stock 
