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E. G. Crosthwaite

Publications and source records attributed to E. G. Crosthwaite.

At least 19 recordsLinked to original sources
USGS1982

Chemical and light-stable isotope characteristics of waters from the Raft River geothermal area and environs, Cassia County, Idaho; Box Elder County, Utah

Chemical and light-stable isotope data are presented for water samples from the Raft River geothermal area and environs. On the basis of chemical character, as defined by a trilinear plot of per cent milliequivalents, and light-stable isotope data, the waters in the geothermal area can be divided into waters that have and have not mixed with cold water. The non-mixed waters have essentially a constant value of light-stable isotopes but show a large variation in chloride content. The variation of chloride composition is not the usual pattern for deep geothermal waters, where it is normally assumed that the deep water has a single chloride composition. Different mixed waters also have hot-water sources of varying chloride composition. Plots of chloride values on cross-sections show that water circulation patterns are confused, with non-mixed waters having different chloride concentrations located in close proximity. Three models can explain the characteristics of the deep geothermal water: (1) in addition to near-surface mixing of cold and hot water, there is deep mixing of two hot waters with the same enthalpy and isotopic composition but differing chloride concentrations to produce the range of chloride concentrations found in the deep geothermal water; (2) there is a single deep hot water, and the range of chloride concentrations is produced by the water passing through a zone of highly soluble materials (most likely in the sedimentary section above the basement) in which waters have different residence times or slightly different circulation paths; (3) the varying chloride concentrations in space have been caused by varying chloride concentrations in the deep feed water through time. Some of this older water has not been flushed from the system by the natural discharge. Although one model may seem more plausible than the others, the available data do not rule out any of them. Data for water samples from the Raft River and Jim Sage Mountains show that water from these areas is probably the source for the cold mixing water determined from end-members on mixing lines. Data for water samples in the Upper Raft River Valley show that the thermal anomaly found at Almo 1 is probably not related to the Raft River geothermal area. The water is different in type as shown by its placement on a trilinear plot, and the isotopes are different enough to show that it is probably a different water. Isotopic compositions of samples from a wide area around the Raft River geothermal system indicate that the likely source of the recharge water is the southern Albion Mountains and western Raft River Mountains. The recharge area is at one end of the Narrows zone, and the geothermal area is along the Narrows zone; thus it is likely that the Narrows zone defines the circulation path.

Geothermics↗
USGS1979

Chemical analyses of ground water related to geothermal investigations in the Teton River area, eastern Idaho

Water samples were collected from 31 wells and springs in eastern Idaho and western Wyoming to help evaluate the potential geothermal resources in the Teton River area, Idaho. The water analyses included the common anions and cations, oxygen-18, deuterium, and several minor elements. Actual temperatures of the sampled thermal waters ranged from 23° to 49°C. Estimated aquifer temperatures, as derived from geochemical thermometers, ranged from 45° to 145°C based on silica concentrations and 45° to 205°C based on sodium-potassium-calcium ratios. Using the cation thermometer, two analyses indicated aquifer temperatures that were lower than the actual measured temperatures. Estimated temperatures using a mixing-model method ranged from 205° to 320°C, the higher temperature being of questionable value. The different methods used to estimate aquifer temperatures showed little correlation. On the basis of isotope data, the warm waters may be of local meteoric origin and have not been heated enough to react significantly with the aquifer rocks, or they originated as precipitation at high altitude and great distance from the area.

Idaho↗
USGS1978

The flood in southeastern Idaho from the Teton Dam failure of June 5, 1976

The failure of the Teton Dam near Newdale, Idaho, June 5, 1976, caused a flood of unprecedented magnitude on the Teton River, lower Henrys Fork, and Snake River upstream from American Falls Reservoir. Eleven lives were lost. More than 180 square miles were inundated and damages reportedly were about $400 million. At the time of failure, the Teton Reservoir contained 251,700 acre ft of water. Approximately 173,000 acre-ft drained through the breached dam within 143 minutes, resulting in a peak discharge of 2.3 million ft 3 /s. A total of about 240,000 acre-ft drained from the reservoir within an 8-hour period. Between Teton Dam and American Falls Reservoir on Snake River, about 100 miles, the peak discharge and flood volume attenuated to 53,500 ft 3 /s is and 160,000 acre-ft, respectively. American Falls Reservoir stored the entire floodflow. The report presents peak discharges, flood volumes, profiles of the water surface, time-of-travel data, and geometric properties of 25 transverse cross sections. Hydrographs of groundwater levels at 50 sites adjacent to the flood area are presented. Analyses of surface water and ground water samples show the effect of the flood flow on quality of water within the flooded area.

Idaho↗
USGS1976

Basic data from five core holes in the Raft River geothermal area, Cassia County, Idaho

Studies of the geothermal aspect-of the Bridge area of the Raft River basin in south-central Idaho (fig. 1) by the U.S. Geological Survey began in 1972 when Young and Mitchell (1973) made a geochemical and geologic reconnaissance of selected thermal waters in Idaho. The Bridge area had been designated the Frazier known geothermal resource area (Frazier KGRA) by the U.S. Geological Survey (Godwin and others-, 1971) . Since 1972, several units of the Geological Survey have studied the area to provide data for the U.S. Energy Research and Development Administration, which proposes to ascertain whether the geothermal resource can be developed for power generation and other uses. The studies include geologic mapping, geophysical surveys, water sampling, test drilling, and studies of all available drill- hole data. A list of reports already prepared on the area is included with this report. Core drilling of five holes began in August 1974 and was completed in March 1975. These holes are referred to as intermediate-depth core holes, principally because in the spring of 1974, 35 auger holes 25 to 98 feet (7.6 to 30 meters) were completed in the area (Crosthwaite, 1974), and the Aerojet Nuclear Company, under the auspices of the U.S. Energy Research and Development Administration, was planning some deep drilling 4,000 to 6,000 feet (1,200 to 1,800 meters) (fig. 1). The purpose of the core drilling was to provide information to test geophysical interpretations of the subsurface structure and lithology and to provide hydrologic and geologic data on the shallow part of the geothermal system. Samples of the core were made available to several divisions and branches of the Geological Survey and to people and agencies outside the Survey. This report presents the basic data from the core holes that had been collected to September 1, 1975, and includes lithologic and geophysical well logs, chemical analyses of water (table 1), and laboratory analyses of cores (table 2) that were completed as of the above date. The data were collected by the Idaho District office, Hydrologic Laboratory, Borehole Geophysics Research Project, and Drilling, Sampling, and Testing Section, all of the Water Resources Division, and the Branch of Central Environmental Geology of the Geologic Divison.

Idaho↗
USGS1974

A progress report on results of test drilling and ground-water investigations of the Snake Plain aquifer, southeastern Idaho: Part 3: Lake Walcott-Bonanza Lake area

Direct-current resistivity soundings and exploratory drilling suggest that the basalt of the Snake River Group is relatively thin in the area along the Snake River that is topographically suitable for pumping large quantities of ground water in exchange for surface water. The formations underlying the Snake River Group appear to have low permeability and probably would not yield large amounts of water. Previous studies have indicated that the southern edge of the Snake Plain aquifer extended to the Snake River. Data presented in this report implies that, in general, the southern boundary should, in fact, be several miles north of the river.

Idaho↗
USGS1973

A progress report on results of test drilling and ground-water investigations of the Snake Plain aquifer, southeastern Idaho: Part 1: Mud Lake Region, 1969-70 and Part 2: Observation Wells South of Arco and West of Aberdeen

The results of drilling test holes to depths of approximately 1,000 feet in the Mud Lake region show that a large part of the region is underlain by both sedimentary deposits and basalt flows. At some locations, predominantly sedimentary deposits were penetrated; at others, basalt flows predominated. The so-called Mud Lake-Market Lake barrier denotes a change in geology. From the vicinity of the barrier area, as described by Stearns, Crandall, and Steward (1938, p. 111), up the water-table gradient for at least a few tens of miles, the saturated geologic section consists predominantly of beds of sediments that are intercalated with numerous basalt flows. Downgradient from the barrier, sedimentary deposits are not common and practically all the water-bearing formations are basalt, at least to the depths explored so far. Thus, the barrier is a transition zone from a sedimentary-basaltic sequence to a basaltic sequence. The sedimentary-basaltic sequence forms a complex hydrologic system in which water occurs under water-table conditions in the upper few tens of feet of saturated material and under artesian conditions in the deeper material in the southwest part of the region. The well data indicate that southwest of the barrier, artesian pressures are not significant. Southwest of the barrier, few sedimentary deposits occur in the basalt section and, as described by Mundorff, Crosthwaite, and Kilburn (1964). ground water occurs in a manner typical of the Snake Plain aquifer. In several wells, artesian pressures are higher in the deeper formations than in the shallower ones, but the reverse was found in a few wells. The available data are not adequate to describe the water-bearing characteristics of the artesian aquifer nor the effects that pumping in one zone would have on adjacent zones. The water-table aquifer yields large quantities of water to irrigation wells.

Idaho↗
USGS1970

Water resources in the Big Lost River Basin, south-central Idaho

The Big Lost River basin occupies about 1,400 square miles in south-central Idaho and drains to the Snake River Plain. The economy in the area is based on irrigation agriculture and stockraising. The basin is underlain by a diverse-assemblage of rocks which range, in age from Precambrian to Holocene. The assemblage is divided into five groups on the basis of their hydrologic characteristics. Carbonate rocks, noncarbonate rocks, cemented alluvial deposits, unconsolidated alluvial deposits, and basalt. The principal aquifer is unconsolidated alluvial fill that is several thousand feet thick in the main valley. The carbonate rocks are the major bedrock aquifer. They absorb a significant amount of precipitation and, in places, are very permeable as evidenced by large springs discharging from or near exposures of carbonate rocks. Only the alluvium, carbonate rock and locally the basalt yield significant amounts of water. A total of about 67,000 acres is irrigated with water diverted from the Big Lost River. The annual flow of the river is highly variable and water-supply deficiencies are common. About 1 out of every 2 years is considered a drought year. In the period 1955-68, about 175 irrigation wells were drilled to provide a supplemental water supply to land irrigated from the canal system and to irrigate an additional 8,500 acres of new land. Average. annual precipitation ranged from 8 inches on the valley floor to about 50 inches at some higher elevations during the base period 1944-68. The estimated water yield of the Big Lost River basin averaged 650 cfs (cubic feet per second) for the base period. Of this amount, 150 cfs was transpired by crops, 75 cfs left the basin as streamflow, and 425 cfs left as ground-water flow. A map of precipitation and estimated values of evapotranspiration were used to construct a water-yield map. A distinctive feature of the Big Lost River basin, is the large interchange of water from surface streams into the ground and from the ground into the surface streams. Large quantities of water disappear in the Chilly, Darlington, and other sinks and reappear above Mackay Narrows, above Moore Canal heading, and in other reaches. A cumulative summary of water yield upstream from selected points in the basin is as follows : Above Howell Ranch: water yield: 345 cfs; surface water: 310 cfs; ground water: 35 cfs Above. Mackay Narrows water yield: 450 cfs; surface water: 325 cfs; ground water: 75 cfs; crop evapotranspiration: 50 cfs Above Arco: water yield: 650 cfs; surface water: 75 cfs; ground water: 425 cfs; crop evapotranspiration: 150 cfs Ground-water pumping affects streamflow in reaches , where the stream and water table are continuous, but the effects of pumping were not measured except locally. Pumping depletes the total water supply by the. amount of the pumped water that is evapotranspired by crops. The part of the pumped water that is not consumed percolates into the ground or runs off over the land surface to the stream. The estimated 425 cfs that leaves the basin as ground-water flow is more than adequate for present and foreseeable needs. However because much of the outflow occurs at considerable depth, the quantity that is salvageable is unknown. Both the surface and ground waters are of good quality and are suitable for most uses. Although these waters are low in total dissolved solids, they tend to be hard or very hard.

Idaho↗
USGS1970

Ground-water aspects of the lower Henrys Fork region, eastern Idaho

The lower Henrys Fork region in eastern Idaho includes the plains and low benches between Ashton and the junction of Henrys Fork and Snake River. The northwestern and western parts of the area are part of the Snake River basalt plain. The central part of the area is occupied by alluvial plains of the Snake, Teton, and Falls Rivers and of Henrys Fork. The alluvial deposits are underlain by basalt. The southeastern part of the area is a bench (Rexburg Bench), chiefly on silicic and basaltic volcanic rocks, which rises gradually to mountain peaks (Big Hole Mountains) southeast of the area. Irrigation wells open to the basalt under the Snake River Plain and the basalt and sands and gravels under the alluvial plains yield large amounts of water with small drawdowns. Irrigation wells in the silicic volcanic rocks and the interbedded ash, pyroclastics, and sedimentary deposits beneath the Rexburg Bench generally yield much less water. The regional water table slopes southwestward beneath the basalt and alluvial plains. It is recharged by precipitation that infiltrates into the ground in the headwaters of Henrys Fork and Falls, and Teton Rivers and by water that moves downward from an extensive perched water body caused by seepage from stream channels and surface-water irrigation. The perched water in part moves vertically down to the regional water table and in part laterally to the streams. Ground water beneath the Rexburg Bench moves generally northwestward to join the regional ground-water body beneath the alluvia,1 and basalt plain, but this area contributes very little recharge to the main aquifer body. Recharge to the regional water table is estimated to average 725,000 acre-feet annually. The regional water table is below the level of the streams in the area, and ground water in the main aquifer, therefore, is not tributary to the streams. Pumping from the regional ground-water reservoir for irrigation or other uses would have no effect on streamflow or surface-water rights within the study area. However, depletion of the underflow would eventually reduce the inflow to American Falls Reservoir, unless the depletion was offset by additional recharge. Total withdrawals of ground water for irrigation in 1962, principally in the Rexburg Bench, were estimated to be 25,000 acre-feet. About 10,000 acre-feet was withdrawn for domestic, municipal, and stock supplies. These withdrawals caused no significant decline in the water table. In the Ashton area, surface-water irrigation has caused water to be perched in basalt above the silicic volcanic rocks, and much of' this perched water contributes to streamflow. Some ground water can be pumped from the basalt for irrigation and other uses. If ground water were pumped for irrigation, the flow of Henrys Fork would be decreased by the amount of pumped water consumed by crops. Water pumped for nonconsumptive use would have little effect on streamflow. Ground-water prospects for irrigation in the Falls River area are not encouraging.

Water Supply Paper↗
USGS1969

Water resources of the Salmon Falls Creek basin, Idaho-Nevada

The northern part of the Salmon Falls Creek basin, referred to as the Salmon Falls tract, contains a large acreage of good agricultural land, but the surface-water supply is inadequate to develop the area fully. Attempts to develop ground water for irrigation have been successful only locally. Specific capacities of wells drilled for irrigation and for test purposes ranged from less than 0.5 to 70 gallons per minute per foot of drawdown. The surface-water supply averages 107,000 acre-feet annually, of which about 76,000 acre-feet is diverted for irrigation. The Idavada Volcanics, the most widespread and oldest water-bearing formation in the Salmon Falls tract, consists of massive, dense, thick flows and blankets of welded silicic tuff with associated fine- to coarse-grained ash, clay, silt, sand, and gravel. Fault zones and jointed rock yield large amounts of water to wells, but massive nonjointed units yield little water. Sand, tuff, and ash beds yield moderate quantities of water. Clay, sandy clay, sand, and pea gravel occur in topographic lows on the Idavada Volcanics. The finegrained sediments yield little water to wells, but the gravel yields moderate quantities. Vesicular porphyritic irregularly jointed olivine basalt flows, which overlie the Idavada Volcanics, underlie almost all the Salmon Falls tract. Lenticular fine-grained sedimentary beds as much as 15 feet thick separate some of the flows. Joints and contacts between flows yield small to moderate amounts of water to wells. Alluvial and windblown deposits blanket most of the tract. Where they occur below the water table, the alluvial deposits yield adequate supplies for stock and domestic wells. Perched water in the alluvium along Deep Creek supplies some stock and domestic wells during most years. Ground-water supplies adequate for domestic and stock use can be obtained everywhere in the tract, but extensive exploration has discovered only five local areas where pumping ground water for irrigation is presently economically feasible. About 8,000 acre-feet was withdrawn for all uses in 1960. Natural discharge of ground water is northward -- toward the Twin Falls South Side Project and the Snake River--and is provisionally estimated to be 115,000 acre-feet annually. Ground water in the Salmon Falls tract has a medium- to high salinity hazard and a low sodium hazard. The salinity does not appear to affect crops presently grown in the tract. The southern part of the Salmon Falls Creek basin, referred to as the upper drainage basin, has little agricultural development and is used mostly for grazing livestock. Silicic volcanic rocks and tuffaceous sedimentary rocks of Tertiary age and alluvial deposits yield water to livestock, domestic, and commercial wells.

Idaho;Nevada↗
USGS1964

Ground water for irrigation in the Snake River Basin in Idaho

The Snake River basin, in southern Idaho, upstream from the mouth of the Powder River in Oregon, includes more than 50 percent of the land area and 65 percent of the total population of the State. More than 2.5 million acres of land is irrigated ; irrigation agriculture and industry allied with agriculture are the basis of the economy of the basin. Most of the easily developed sources of surface water are fully utilized, and few storage sites remain where water could be made available to irrigate lands under present economic conditions. Because surface-water supplies have be come more difficult to obtain, use of ground water has increased greatly. At the present time (1959), about 600,000 acres of land is irrigated with ground water. Ground-water development has been concentrated in areas where large amounts of water are available beneath or adjacent to tracts of arable land and where the depth to water is not excessive under the current economy. Under these criteria, many of the most favorable areas already have been developed; however, tremendous volumes of water are still available for development. In some places, water occurs at depths considered near or beyond the limit for economic recovery, whereas in some other places, water is reasonably close to the surface but no arable land is available in the vicinity. In other parts of the basin large tracts of arable land are without available water supply. Thus the chief tasks in development of the ground-water resources include not only locating and evaluating ground-water supplies but also the planning necessary to bring the water to the land. Irrigation began in the 1860's ; at the present time more than 10 million acre feet of surface water, some of which is recirculated water, is diverted annually for irrigation of more than 2.5 million acres. Diversion of this large quantity of water has had a marked effect on the ground-water regimen. In some areas, the water table has risen more than 100 feet and the discharge of some springs has more than doubled. Large-scale development of ground water began after World War II, and it is estimated that in 1959 about 1,500,000 acre-feet of ground water was pumped for irrigation of the 600,000 acres irrigated wholly with ground water in addition to a substantial amount of ground water pumped to supplement surface-water supplies. Ground water is also the principal source of supply for municipal, industrial, and domestic use. The water regimen in the Snake River basin is greatly influenced by the geology. The rocks forming the mountains are largely consolidated rocks of low permeability; however, a fairly deep and porous subsoil has formed on them by decay and disintegration of the parent rock. Broad intermontane valleys and basins are partly filled with alluvial sand and gravel. The subsoil and alluvial materials are utilized very little as a source of water supply but are important as seasonal ground-water reservoirs because they store water during periods of high rainfall and snowmelt. Discharge from these reservoirs maintains stream flow during periods of surface runoff. Because these aquifers are fairly thin, they drain rapidly and are considerably depleted at the end of each dry cycle. The plain and plateau areas and tributary valleys, on the other hand, are underlain chiefly by rocks of high permeability and porosity. These rocks, mostly basaltic lava flows and alluvial materials, constitute a reservoir which fluctuates only slightly from season to season. Large amounts' of water are withdrawn from them for irrigation and other uses, and discharge from the Snake Plain aquifer is an important part of the total flow of the Snake River downstream from Hagerman Valley. The ultimate source of ground water in the basin is precipitation on the basin. In the mountainous areas, aquifers mostly are recharged directly by precipitation.

Idaho↗
USGS1962

Ground-water reconnaissance in Round Valley, Custer County, Idaho

Round Valley in central Idaho contains alluvial deposits of Pleistocene and Recent age which yield adequate supplies of ground water for stock and domestic wells. The alluvial deposits are underlain by Challis Volcanics of Oligocene or Early Miocene age and a few wells obtain domestic and stock water from the basalt, iatite, andesite, and rhyolite which are the principal rocks in the Challis. Very crude estimates indicate that the average annual recharge to the alluvium and Challis Volcanics from precipitation and irrigation is 50,000 acre-feet. Geologic and well data suggest that sufficient ground water might be obtained for irrigation supplies at some places.

Idaho↗
USGS1962

Ground-water reconnaissance of the Sailor Creek area, Owyhee, Elmore, and Twin Falls Counties, Idaho

This reports evaluates the ground-water resources of about 1,000 square miles in the semiarid uplands south of the Snake River between Bruneau River and Salmon Falls Creek. The outcropping rocks are the Idavada Volcanics of Pliocene age, and the Idaho Group of Pliocene and Plieistocene age, consisting of the Banbury Basalt of middle Pliocene age and overlying predominantly sedimentary deposits of middle Pliocene through middle Pleistocene age. These rocks dip gently northward. The volcanic rocks are the best aquifers, but the yield of water from the sedimentary deposits is adequate for domestic and stock use. About 6,000 acre-feet of water is withdrawn annually from the Idavada Volcanics by 9 irrigation wells to irrigate about 3,000 acres. Only a few tends of acre-feet of water withdrawn from the other formations. The regional dip of the rocks induces weak artesian conditions in the volcanic rocks and somewhat higher artesian head in the sedimentary rocks. Estimated depth to water ranges from less than 250 feet to more than 750 feet, as shown in an accompanying map. The eastern part of the area appears to be more favorable for the development of ground water for irrigation than the western part because of better aquifers at shallower depth.

Idaho↗
USGS1957

Ground-water possibilities south of the Snake River between Twin Falls and Pocatello, Idaho

The Snake River Plain and tributary valleys south of the Snake River between Twin Falls and Pocatello, Idaho (here called the South Side area), contain about 180,000 acres of irrigated land, of which 145,000 acres is irrigated with surface water and 35,000 is irrigated wholly or partly with ground water. The area also contains more than 200,000 acres of arable land that is idle or used only for grazing because it lacks irrigation water. Most of the surface-water supply is already used or reserved, and some land now irrigated needs supplemental water. The climate of the area ranges from semiarid on the Snake River Plain to subhumid on higher mountains. The average annual precipitation at lowland stations ranges from about 9 to 12 inches. The principal sources of ground water are extrusive volcanic rocks of silicic to intermediate composition, basalt, and sand and gravel. Ground water occurs commonly under artesian conditions in the silicic to intermediate volcanic rocks and in sand and gravel tongues and lenses in lake beds. Basalt and alluvium commonly contain unconfined water. The area of this report is divided into 13 roughly defined ground-water districts, some of which are further divided into subdistricts. The known geologic and hydrologic factors of each area are summarized and a preliminary appraisal is made of the ground-water resources in relation to land resources and to the regimen of streams. The current state of development, proposed new developments, and ground-water potential of each division are discussed. The Dry Creek district is the most intensively irrigated area in Idaho in which wells furnish the water supply. Ground water occurs under both artesian and water-table conditions. More than 53,000 acre-feet of ground water was pumped in 1954. There are large areas of undeveloped arable land in the district, but pumping in some parts of the district currently is approaching or surpasses the perennial yield of the ground-water reservoirs. The Golden Valley district contains considerable arable land but, owing to the relatively great depth to water and the generally poor yield of wells, the prospects for extensive ground-water development are not promising. In the Oakley district ground water is pumped from alluvium to supplement surface water and to bring new land into production. The ground water will be fully exploited within a few years if the present rate of development by individual landowners continues. The total area of nonirrigated land far exceeds the amount that could be irrigated with indigenous ground water. Both artesian and unconfined water occur in the Burley district. Most existing wells tap unconfined water in the southern part where there are still large tracts of idle arable land. Pumping lifts are rather high. The South Walcott district contains a considerable acreage of arable land and is underlain by excellent aquifers. The effect that heavy pumping would have on the flow of the Raft and Snake Rivers and on seepage from Lake Walcott is Taot well understood. Presumably substantial pumping would be feasible without direct deleterious effects. The Raft River basin, including the Elba and Almo-Yost subbasins, is the largest district in the South Side area. Ground water occurs in both unconfined and artesian aquifers. Possibly as much as 150,000 acres of dry land is irrigable, but the ground-water supply presumably is sufficient to irrigate only a few thousand acres in addition to the approximately 40,000 now irrigated with surface and ground water. Pumping of wells at some locations would deplete the base flow of the Raft River and would be competitive with surface-water use. The United States Bureau of Reclamation has started construction of the Michaud Flats Irrigation Project in the Western Michaud Flats district. The adopted reclamation plan is to irrigate about 10,000 acres, using surface water pumped from American Falls Reservoir and ground water pumped from wells. Ground water in part of the district is tributary to the reservoir. Withdrawals of ground water will be compensated in part by the return of waste water to the reservoir and to the Snake River. The Eastern Michaud Flats district contains more arable land and has better aquifers than the Western Michaud Flats district, but pumping might reduce noticeably the discharge of ground water to the American Falls Reservoir. The Bureau of Indian Affairs plans to develop about 13,600 acres of Indian land with water stored in Palisades and American Falls Reservoirs. Virtually nothing is known about ground-water conditions in the Arbon and Rockland Valleys and in several small areas such as the Basin district, the Albion basin, and along the northern border of the Sublett Range. Preliminary studies have been made in three areas, the Dry Creek, Raft River, and Western. Michaud Flats districts. None has been studied comprehensively. The available data for each district are summarized in tabular form. Further investigations in the area are needed and should include accurate hydrologic mapping. Studies are needed of the sources and amounts of groundwater recharge, of the effects of ground-water withdrawals on the total water supply, and of numerous related problems.

Idaho↗
USGS1957

Ground-water geology of the Bruneau–Grand View area, Owyhee County, Idaho

The Bruneau-Grand View area is part of an artesian basin in northern Owyhee County, Idaho. The area described in this report comprises about 600 square miles, largely of undeveloped public domain, much of which is open, or may be opened, for desert-entry filing. Many irrigation-entry applications to the Federal Government are pending, and information about ground-water geology is needed by local citizens and well drillers, by Federal agencies that have custody of the land, and by local and State agencies that administer water rights. The areal geology and ground-water conditions in the Bruneau-Grand View area seemingly typify several basins in southwestern Idaho, and this study is a step toward definition and analysis of regional problems in ground-water geology and the occurrence and availability of ground water for irrigation or other large-scale uses. Owyhee County is subdivided physiographically into a plateau area, the Owyhee uplift, and the Snake River valley. The Bruneau-Grand View area is largely within the Snake River valley. The climate is arid and irrigation is essential for stable agricultural development. Nearly all usable indigenous surface water in the area is appropriated, including freshet flow in the Bruneau River, which is used for power generation at the C. J. Strike Dam. However, with storage facilities additional land could be irrigated, and some land may be irrigated with Snake River water if suitable reclamation projects are constructed. Sedimentary and igneous rocks exposed in the area range in age from Miocene to Recent. The igneous rocks include silicic and basic intrusive and extrusive bodies, and the sedimentary rocks are compacted stream and lake sediments. The rocks contain economically important artesian aquifers; the principal ones are volcanic rocks in which ground water is imperfectly confined beneath sediments of the Idaho formation, thus forming a leaky artesian system. The altitude of the piezometric surface of the artesian water does not exceed about 2,700 feet above mean sea level. In some areas, where the land surface is below that altitude, the artesian system discharges water through springs and seeps and locally causes waterlogging and development of alkali soil. In chemical quality much of the water is unsuitable for irrigation and domestic use. The water contains a relatively moderate amount of dissolved solids, but the percent sodium and the concentration of fluoride are excessive for some uses. The quality of the water for irrigation ranges from excellent in the southern part of the artesian system to unsuitable in the northern part. All the artesian ground water that was sampled contained excessive amounts of fluoride. There is a substantial supply of undeveloped artesian water in the area, but sustained use of the water for irrigation may not be feasible unless provisions can be made for adequate soil drainage and soil amendment, because of the high percentage of sodium in the water. Detailed hydrologic and geologic study of the area should precede development.

Idaho↗