4. Diagram showing appropriated and unappropriated waters of 29 5. Diagram showing appropriated and unappropriated waters of 33 6. Diagram showing appropriated and unappropriated waters of 34 7. Diagram showing appropriated and unappropriated waters of 34 8. Diagram showing appropriated and unappropriated waters of 36 9. Diagram of water supply of Cache Valley, exclusive of Bear River. 12. Narrows of Ogden River. 13. Diagram illustrating inflow and outflow of Ogden Valley. 41 42 44 45 46 7 LETTER OF TRANSMITTAL. DEPARTMENT OF THE INTERIOR, Washington, April 13, 1897. SIR: I have the honor to transmit herewith a paper entitled Seepage Waters of Northern Utah, by Samuel Fortier, professor of irrigation engineering at the Agricultural College at Logan, Utah. The facts herein, presented are based upon field work carried on mainly during the summer of 1896, and have special value in illustrating conditions which prevail to a greater or less degree throughout all irrigated lands, especially within inclosed valleys or on long, narrow drainage systems. One of the matters which most complicate and embarrass the adjudication of water rights and the strict enforcement of priorities of appropriation arises from the fact that a considerable volume of water available for irrigation during the critical season of the year, when the crops are maturing, comes from the seepage from lands higher upstream to which water has been applied earlier in the year. In some cases these lands have been irrigated in defiance of a strict construction of the law regarding the priority of right to use water, but it has been claimed that such use, instead of being a detriment to the lands below, has been a benefit, and, in fact, that there has been more water available in consequence of this use than could otherwise be had. The determination of these matters requires careful measurement and study in each case, but the work of Professor Fortier serves to indicate what may be expected under similar conditions and illustrates methods applicable to this examination. Very respectfully, F. H. NEWELL, Hydrographer in Charge. Hon. CHARLES D. WALCOTT, Director United States Geological Survey. SEEPAGE WATER OF NORTHERN UTAH. BY SAMUEL FORTIER. LOCATION AND PURPOSE OF THE INVESTIGATION. The term " seepage water" is used by the irrigators of the West to designate the water which reaches the lowest grounds or the stream channels, swelling the latter by imperceptible degrees and keeping up the flow long after the rains have ceased and the snow has melted. The word "seepage" is applied particularly to the water which begins to appear in spots below irrigation canals and cultivated fields, usually some months or even years after irrigation has been introduced, and which tends to convert the lowlands into marshes and gives rise to springs, which in turn may be employed in watering other fields. The importance of a thorough knowledge of the behavior of seepage water is obvious when consideration is given to the close relationship which exists between the available water supply and the material prosperity of the arid region where irrigation is practiced. This is particularly true of Utah, where every readily available source of supply has long since been utilized and where the rapidly increasing agricultural population necessitates the complete utilization of all fresh waters. The measurements and investigations of seepage water described in this paper have been confined mainly to Cache Valley, being included within three counties in northern Utah, Weber, Boxelder, and Cache, and one county, Oneida, in Idaho. The conditions may be taken as fairly typical of those in the entire State, and to a less extent of those of adjacent States. A full knowledge of the seepage water will be of inestimable value in the development of Cache Valley, owing to the conditions now existing. The towns and farming communities were settled for the most part from 30 to 40 years ago. The tributaries of Bear River have supplied all irrigating waters, and many of the ditches and canals have water rights extending over a period of 30 years. These early ditches were the first built to divert water from Bear River and its tributaries, and according to the law of prior appropriation which prevails in Utah, Wyoming, and Idaho, the three States through which Bear River flows, the early canals of Cache Valley have water rights prior to all others. Boxelder County has |