| OCR Text |
Show STATE ENGINEER, COLORADO 41 cycle of stream-flow, culminating in the extremely dry year of 1902, shocked the stream systems of Colorado both internally and externally, and led to unwarranted but restricted ideas of water supply and future development both within and without the State. Additional withdrawal of water in lower states, combined with reduction in stream-flow by the upper state, imposed an abnormal demand on stream-flow in low years, and resulted temporarily in depleted rivers. These conditions led to much apprehension concerning sufficiency of water supply, both present and future, and in some instances crystallized into interstate water litigation against Colorado, water embargoes against Colorado, or smouldering dissatisfaction over interstate relations. Generally the water shortages causing interstate strife occurred, at a period in irrigation history of several river basins, prior to the time when large areas had commenced to function as to return-flow. Return-flow is now becom-ming pronounced in irrigated river valleys and a large factor in water supply. A notable example of such return-flow is that section of the North Platte River between the Wyoming Line and Bridgeport, Nebraska, where, in 1924, measured return-flow amounted to 550,000 acre-feet per year. Fifteen years ago return-flow in that area was a negligible factor in water supply. In the San Luis Valley, Colorado, at the headwaters of the Rio Grande, artificial drainage is progressing rapidly, and return-flow and drainage waters returned to the main Rio Grande (1924) exceeded 100,000 acre-feet per year. The heavy return-flow of the South Platte River in eastern Colorado is so well known, and substantial expansion in irrigated areas from it is so great, that specific comment is unnecessary. Headgate diversions are no longer a "measuring stick'' of water supply utilization of river basins. Instead, the pioneer method of water analysis must yield to the economic basis of "Consumptive Use" in studies of river basins, both as to a limit of development and interstate apportionment. Careful and exhaustive studies of water supply of Colorado's interstate rivers have been completed, not only as to Colorado but also as to the irrigation needs of lower states. These studies point a way to increased development equal to the fondest ambitions and hopes of several river communities in lower states. Litigation having proven an unsatisfactory solution of Colorado interstate water problems, the more rational method of interstate river treaties or compacts was substituted, and is proving a much more satisfactory basis for adjusting perplexing water conflicts. The object of the compact idea is to settle the title to river-flow as between states in order that present development may be protected and future development may avoid delay and litigation. To Delph E. Carpenter, Colorado's foremost irrigation authority, credit should be given for originating the "Compact" or treaty method of interstate adjustments. Irrigation development is not static, and conditions surrounding water utilization should be elastic to meet the changing con- |
