The Reclamation Act of 1902, as amended, is the basic legislation governing the distribution of water from federal projects for irrigation purposes. In the three-quarters of a century since the passage of this Act, technological, economic, and legal developments have forced a reappraisal of the original intent of the Reclamation laws. Several proposals have been made to amend these laws and enforce provisions that put the current distribution of the rights to public water and related land resources in jeopardy. This study attempts to evaluate these proposed amendments in terms of the irrigation rights that would be displaced if the amendments were rigidly enforced in three of Oregon's largest federal irrigation districts. The method of analysis proceeds by combining secondary data on land ownership with primary survey data on leasing arrangements to generate a distribution of farm sizes for each district. Each farming unit as a whole is then evaluated for any excess acreage that would be displaced from applying the ownership, leasing, and residency provisions of each of the proposals. Excess acreage is summed and extrapolated over the irrigation district to provide an estimate of the effect of enforcing each proposal in each district. The results of the analysis indicate that the various proposed restrictions will result in widely different sets of effects. Two of the proposals, that of the Department of Interior and that of National Land for People, are restrictive enough to cause 17,000 and 23,000 acres of excess land, respectively, across all three irrigation districts. The other two proposals analyzed, that of Senators Church/Hatfield, and that of Farm/Water Alliance, will result in little or no excess land in these districts. / Graduation date: 1980