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Show Chapter 6 Elements of a Program for Ultimate Development of Water Resources The semiarid Rio Grande Basin presents many complex problems which must be considered in planning long-range water and related land re- sources developments. It has a long agricultural history both in irrigated farming and in raising live- stock. Except in local areas where irrigation stor- age or ground water supplies are adequate, there is generally a shortage in the water supply; there is more land suitable for irrigation than water for that purpose. All surface water supplies have been appropriated and overdraft of ground water is taking place in some areas. Improper use of land and water re- sources in this arid region with infrequent but in- tense storms has accelerated the natural erosion rate and led to severe erosion in range and forest lands and to waterlogging and leaching of irrigated areas. Sedimentation in the main streams has ag- gravated flood problems and made proper drainage difficult. Allocation of water also involves consid- eration of interstate and international agreements. Optimum use of water resources must be predicated on promoting maximum practicable use of land and water consistent with rights established under State laws and the various interstate compacts and inter- national treaties between the United States and Mexico. In the upper part of the Pecos sub-basin and in the middle section of the upper Rio Grande sub-basin are many depressed areas in which the land and water resources cannot be treated apart from the rural population which has brought about the pres- ent unsatisfactory conditions. Most of these prob- lem areas are in the smaller valleys along tributaries of the Rio Grande and Pecos Rivers, inhabited chiefly by Spanish-American and Pueblo Indian communities The Middle Rio Grande Valley proper suffers from severe water shortages and drainage problems and most of the watershed range lands are seriously depleted and eroded. However, these physical conditions are similar to those found in many other irrigated sections of the Southwest. They can be remedied by engineering works and wise use of the land and water, and these improve- ments are slowly taking place. But in many of the tributary valleys the rural pop- ulation has far outgrown the land and water re- sources available for its direct support. Because there are few other opportunities for gainful em- ployment, too many people are still dependent on the land, supplemented by occasional wage work, for a living. This has resulted in dividing the avail- able irrigated land into subsistence units which are not true farms, for the most part, and which cannot make the most efficient use of land and water. Live- stock of these communities overcrowd the nearby range, which keeps nature from maintaining an ade- quate vegetal cover and causes serious erosion. In these problem areas little can be done toward per- manent improvement of living conditions and the most productive use of the land and water until the surplus rural population is absorbed by nonf arm em- ployment, relieving this excessive pressure on the land. Elements of a Program In the light of current knowledge, a sound eco- nomic program for the Rio Grande Basin which would assure the most practicable and complete development of water, land, and associated re- sources should provide for ultimate accomplishment of the following functional objectives. 345 |
