More water-water from the Colorado River-is the hope of the future. Man cannot govern the amount of water that falls as rain and snow, but he can prevent its needless waste by careful planning and building of dams, canals, power plants, and other works that will so control and conserve it that more water will be available for his use.

A survey of the basin's resources and economic activities not only establishes water as the critical materialthe most important natural resource-but focuses attention on what present use is being made of that precious material and how it can best be used in the future to serve man's various needs.

This chapter describes the nature and extent of present water uses in the Colorado River Basin and outlines potential projects for beneficial use of all the water of the entire river system. Such a basin-wide perspective of ultimate potentialities will provide for planning coordinated development on a sound basis. All beneficial uses, including the irrigation of land, the production of hydroelectric power, the preservation of fish and wildlife, and the enhancement of recreational areas, together with the control of floods and silt, and the restoration of groundwater levels were taken into account in formulating the potential projects. Domestic, municipal, and industrial water supplies are planned for a few areas where demands are now established, and adaptations for other such uses may be made as needs arise.

The construction of all potential projects described and their operation, added to present water uses, would create a demand for more water than normally is available in the river system. Certain of the projects are key units or for other reasons hold initial preference in the plan of ultimate development. Those could be constructed at once as the next phase of river control and utilization. Later selection of projects will be influenced by more complete surveys, cost estimates, stream flow records, and by agreement among the respective States as to the allocation of the water which has already been apportioned between the upper and lower basins.

Estimates of present depletions of the water supply of the Colorado River and of future depletions from construction of potential projects are based on average flows during the long-time period of record, 1897 to 1943 in

clusive. Depletions are considered to be the reductions in virgin stream flow of the Colorado River at Lee Ferry and at the international boundary resulting from man-made improvements.

The upper and lower basins are discussed separately and each is further divided, to permit more detailed treatment of specific areas, into the divisions suggested by physical characteristics: the Green, Grand, and San Juan divisions in the upper basin, and the Little Colorado, Virgin, Boulder, and Gila divisions in the lower basin. (See chapter I.)

State maps, one for each of the seven Colorado River Basin States, entitled "Water Resources Development, Colorado River Basin," showing the location of irrigated and irrigable lands, existing and potential reservoir sites, main canals, and other features of existing and potential projects for the development of water resources, are included as an appendix of this report.

UPPER BASIN

An area larger than New York, Pennsylvania, and New Jersey combined, is tributary to the Colorado River above Lee Ferry. This is the Upper Colorado Basin. It includes parts of five Rocky Mountain States. Rimmed by some of the highest mountains in America, snowcapped throughout the year, it is the source of the greater part of the water reaching the Colorado River.

Within the basin 1,325,000 acres are now irrigated. Much of this irrigated acreage produces pasture grasses and hay and serves as a home base for livestock grazing on the vastly larger areas of range and forest land. Some irrigated lands, however, are devoted to more intensive farming with vegetables and fruits as chief crops. The construction of potential projects outlined in this chapter would practically double the upper basin's irrigated area and bring supplemental water to half a million acres now lacking a full supply. These potential projects would bring water to lands determined by land classification to be arable. Vast areas of native pasture lands, mostly at high elevations, were not so classified, but would become more productive under irrigation. These lands have not

be increased 28 times with full development of water resources in the basin.

The exportation of water for use in adjoining basins, now averaging only about 184,000 acre-feet annually, is only 6 percent of ultimate potentialities, if it were not for limitations of the Colorado River Compact. In presenting possible exportations of water from the upper basin to the adjoining North Platte, South Platte, Arkansas, Rio Grande, and Bonneville Basins it is contemplated that appropriate understandings will be reached between representatives of both the exporting and importing basins concerning the manner in which such projects shall be constructed and operated to safeguard within the upper basin the vested and future rights in irrigation; to preserve fishing and recreational facilities and scenic attractions; to maintain conditions of river flow for the benefit of local domestic uses and sanitary purposes; and to utilize the waters for irrigation, power, industrial development and other purposes, in such a manner that the greatest benefits are realized.

Flows of the Green River and its tributaries are greatest in the spring when mountain snows are melting. About 60 percent of the annual run-off occurs during April, May, and June. Late summer flows are extremely low. Storage is necessary for regulation of the flood runoff to furnish supplemental water to lands lacking a dependable supply, to provide irrigation water to lands still undeveloped, to permit diversion of surplus water to adjoining basins, and for the production of firm power.

The streams emerge from canyons relatively clear and pure but pick up some alkali in the valleys, especially in late summer when return flows from irrigation are high. Run-off from raw shale beds along LaBarge, Fontenelle, Big Sandy, and Bitter Creeks and Strawberry River carries a fairly high salt concentration, a danger that must be recognized and studied further in planning future development. Heavier concentration may result from expanded irrigation, from increased exportation of pure water from the stream heads, and from reservoir evaporation. Silt is not prevalent enough in streams of the Green River Basin to constitute a serious problem.

Development of ground water resources in the Green River Basin has been limited to a few small wells for stockwatering and domestic uses. Some water obtained from wells is heavily charged with minerals. Neither the quality nor the quantity of ground water now developed is indicative of any substantial use of water from wells for irrigation in the future. Hot springs at Steamboat Springs, Colorado, are the largest of three spring areas in the Yampa River Basin.

PRESENT DEVELOPMENT OF WATER RESOURCES

Irrigation accounts for the greatest use of Green River water at present. Homes, cities, livestock, and industries consume necessary but comparatively small quantities. Five small hydroelectric power installations on tributary streams serve rural areas. Streams and lakes are natural spawning waters for fish, and the mountains and valleys are habitat for wildlife; but little has been done to improve natural conditions.

Irrigation within the Green River Basin commenced in 1854 when Mormon pioneers established old Fort Supply in Wyoming on their immigrant trail and diverted water from Blacks Fork onto adjacent land. From this humble beginning progress has been slow. The short growing season, particularly in the upper Green River Basin in Wyoming, limits the kinds of crops that can be grown successfully. The greater part of the Uinta Basin was established as an Indian reservation in 1861 and lands unoccupied by Indians were not opened to settlement until 1905. The remoteness of much of the basin from railroads has also slowed agricultural progress, but with the growth of highway transportation this disadvantage may largely be

overcome.

Approximately 571,000 acres in the Green River Basin are now irrigated and 11,470 acres more will be provided water through works now being constructed. Most of the present use is by simple diversions and easily constructed canals. A large part of these lands suffer late-season water shortages. Some water from tributaries of the Duchesne, Price, and San Rafael Rivers in the Green River Basin is exported westward to the Bonneville Basin in Utah.

Present development of water resources in the Green River division is discussed in more detail under four subdivisions: (1) Upper Green River Basin, (2) Yampa and White River Basins, (3) Uinta Basin, and (4) Price and San Rafael River Basins.

Upper Green River Basin.-This area extends from the headwaters of the Green River down to the Yampa River which enters the main stream from the east in Colorado. It is about 90 percent in Wyoming, with the remainder in Utah and Colorado.

Irrigation development in this area includes numerous community or privately owned ditches and small reservoirs. Ditches divert at frequent intervals along the streams. Most of them have been constructed and are maintained at minimum expense. It is common for farmers to have individual ditches, and in some cases single farms are served by several ditches diverting from a stream at different points. In addition to many small irrigation reservoirs and stock-watering ponds, 17 reservoirs with capacities of 1,000 acre-feet or more, all constructed by private interests, are distributed throughout the basin. Private holdings of irrigated land are large. Most are hay-producing ranches, varying from a few acres to several thousand acres.

The Eden project, being rehabilitated and extended by the Bureau of Reclamation, is the only Federal irrigation project in the upper Green River Basin. As authorized in 1940, the project will furnish a full or supplemental irrigation supply for 20,000 acres. Surplus flows of Big Sandy Creek will be stored in Big Sandy Reservoir No. 2, to have a capacity of 35,000 acre-feet, for use on project lands. With completion of the Eden project, 245,660 acres in the upper Green River Basin will be irrigated.

The seven existing power plants in this subdivision include only one small hydroelectric development with a capacity of 150 kilowatts. Most of the energy is generated at four steamplants and is used largely for coal mining. There are no interconnections with outside systems.

Most of the irrigated lands are along river or creek bottoms, with only a few small areas on benches from 20 to 40 feet above stream beds. Diversions are made through numerous community or privately owned ditches. Water is stored in several small reservoirs, capacities of which total 14,500 acre-feet. These reservoirs have been built at minimum expense to serve lands belonging to only a few operators. Some of the reservoirs have not been used in recent years because their dams were considered unsafe.

A 200-kilowatt power plant at Meeker, Colo., is the only hydroelectric development in these basins. A 4,250kilowatt plant at McGregor and a 375-kilowatt plant at Meeker, both steam-electric, furnish most of the power used in the area.

Uinta Basin.-The Uinta Basin, as considered in this report, includes areas drained by the Duchesne River, and Ashley, Brush, Willow and Minnie Maud Creeks. The drainage area is entirely in northeastern Utah, and except for the Willow Creek drainage is west of Green River. The Green River channel from the Yampa River to Minnie Maud Creek is considered to be within the Uinta Basin.

Irrigated lands within the Uinta Basin amount to 165,600 acres, most of which is short of late-season water. Indians once owned 77,000 acres of irrigated land in this basin but have sold 25,300 acres. Present regulations prevent sales and limit leases. In 1942 Indians leased 26,200 acres, cultivating only 11,800 acres themselves.

Sixteen Government-built main canals and six small ditches make up the Indian irrigation system, totaling 162 miles of canal and 633 miles of laterals and sublaterals. Indian water rights were established before unoccupied lands in the reservation area were opened to outside settlers. Consequently their primary rights consume all lateseason water of the Duchesne River and its tributaries, leaving white-owned lands critically short. In normal years Indian lands receive enough water, but they would profit by storage regulation to provide better seasonal distribution. No storage reservoirs have been constructed for Indian lands.

Throughout the basin white settlers have organized mutual irrigation companies for the purpose of building irrigation works and distributing water. Private diversions are largely limited to tributary streams and springs.

Serving Uinta Basin lands are 28 reservoirs, some very small, with a total storage capacity of 74,000 acre-feet. More than half of this was provided by the Bureau of Reclamation with the construction of the Moon Lake project (1935-38), which includes Moon Lake and Midview Reservoirs. Water from Strawberry Valley Reservoir, constructed in 1913 on Strawberry River as one of the earlier Bureau of Reclamation developments, is exported westward by tunnel to lands in the Bonneville

Basin. The Duchesne Tunnel, to divert water from the Duchesne River to the Bonneville Basin, is now under construction as a unit of the Provo River project. When completed it will export annually an average of 32,000 acre-feet of flood water from the Colorado River Basin.

The four existing power developments include one Diesel and three small hydroelectric plants, with combined capacities of 2,050 kilowatts. There are no connections with plants outside the Uinta Basin.

Price and San Rafael River Basins.-Adjacent to each other, these two basins are in east central Utah. Both the Price and San Rafael Rivers originate on the eastern slope of the Wasatch Mountains and flow southeast in parallel courses to Green River. The Green River channel from Minnie Maud Creek to the Colorado River, for convenience, is considered as a part of the Price and San Rafael Basin area.

Within this area 15,970 acres are irrigated from Price River, 35,250 from San Rafael River and 2,820 acres from Green River, thus aggregating 54,040 acres. At one time 25,000 acres were irrigated from Price River, but poor soil, erosion, and alkali have caused the irrigated area to be reduced to its present size. Any future expansion of irrigation to new areas is expected to be accompanied by abandonment of a less productive area now irrigated.

Natural flows of Price River are supplemented for irrigation by releases from the Scofield Reservoir on Price River. Scofield Dam, constructed by private interests in 1926 to impound 61,000 acre-feet of water, partially failed 2 years later. For safety, storage has since been restricted to 30,000 acre-feet. The Bureau of Reclamation was authorized to replace this dam and in 1943 began construction of a new dam 800 feet downstream. The

reservoir formed by this new dam will have a capacity of 73,000 acre-feet of water, 30,000 acre-feet of which will replace the usable capacity behind the old dam, and 8,000 acre-feet will be reserved for fish propagation. The remaining 35,000 acre-feet will be held for a time by the United States and ultimately used to store water for irrigating Price River lands in exchange for other water exported from high tributaries of the Price River to the Bonneville Basin.

Huntington, Cottonwood, and Ferron Creeks are the sources of irrigation supply in the San Rafael Basin, each serving independent areas with irrigation companies distributing the flow of each stream. Storage capacity aggregates 5,875 acre-feet on Huntington Creek and 1,310 acre-feet on Ferron Creek. Late-season water shortages are most acute in the Huntington Creek area where the acreage irrigated is greatest in proportion to the available water. Eleven small projects, including the Sanpete project (Ephraim and Spring City tunnels) constructed by the Bureau of Reclamation, divert flood water westward to the Bonneville Basin.

The lands irrigated directly from Green River are in the vicinity of Green River, Utah, and are served mostly by pumping.

Water piped from tributary streams and springs supplies larger municipalities in the Price and San Rafael River Basins. No electric power is produced. Transmission lines carry power into the area from the Bonneville Basin to the west.

Summary. The following tables summarize present irrigation developments in the Green division showing the more important reservoirs, areas irrigated, estimated stream depletion by water consumed within the basin, and amounts exported to adjacent basins.