Geology and availability of ground water on the Ute Mountain Indian Reservation, Colorado and New Mexico
Explore the source record for details and available documents.
Water Supply Paper↗
SEARCH · Search USGS
Results for “Water Supply Paper”
Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Ground-water resources of the Wind River Indian Reservation, Wyoming
The area of this investigation is in the western part of the Wind River Basin and includes parts of the Absaroka, Washakie, Wind River, and Owl Creek Mountains. The purposes of the study were to determine the general hydrologic properties of the rocks in the area and the occurrence and quality c f the water in them. Structurally, the area is a downfolded basin surrounded by upfolded mountain ranges. Igneous and metamorphic rocks of Precambrian age are exposed in the mountains: folded sedimentary rocks representing all geologic periods, except the Silurian, crop out along the margins of the basin; and relatively flat-lying Tertiary rocks are at the surface in the central part of the basin. Surficial sand and gravel deposits of Quaternary age occur along streams and underlie numerous terraces throughout the basin. The potential yield and quality of water from most rocks in the area are poorly known, but estimates are possible, based on local well data and on data concerning similar rocks in nearby areas. Yields of more than 1,000 gpm are possible from the rocks comprising the Bighorn Dolomite (Ordovician), Darby Formation (Devonian), Madison Limestone (Mississippian), and Tensleep Sandstone (Pennsylvanian). Total dissolved solids in the water range from about 300 to 3,000 ppm. Yields of as much as several hundred gallons per minute are possible from the Nugget Sandstone (Jurassic? and Triassic?). Yields of 20 gpm or more are possible from the Crow Mountain Sandstone (Triassic) and Sundance Formation (Jurassic). Dissolved solids are generally high but are less than 1,000 ppm near outcrops in some locations. The Cloverly and Morrison (Cretaceous and Jurassic), Mesaverde (Cretaceous) and Lance(?) (Cretaceous) Formations may yield as much as several hundred gallons per minute, but most wells in Cretaceous rocks yield less than 20 gpm. Dissolved solids generally range from 1,000 to 5,000 ppm but may be higher. In some areas, water with less than 1,000 ppm dissolved solids may be available from the Cloverly and Morrison Formations. Tertiary rocks yield a few to several hundred gallons per minute and dissolved solids generally range from 1,000 to 5,000 ppm. Wells in the Wind River Formation (Eocene) yield about 1.-500 gpm of water having dissolved solids of about 200-5,000 ppm. Yields of a few to several hundred gallons per minute are available from alluvium (Quaternary). Dissolved solids range from about 200 to 5,000 ppm. Many parts of the Wind River Irrigation Project have become waterlogged. The relation of drainage problems to geology and the character and thickness of rocks in the irrigated areas are partly defined by sections drawn on the basis of test drilling. The drainage-problem areas are classified according to geologic similarities into five general groups: flood plains, terraces, underfit-stream valleys, slopes, and transitional areas. Drainage can be improved by open drains, buried drains, relief wells, and pumped wells or by pumping from sumps or drains. The methods that will be most successful depend on the local geologic and hydrologic conditions. In several areas, the most effective means of relieving the drainage problem would be to reduce the amount of infiltration of water by lining canals and ditches and by reducing irrigation water applications to the optimum. Water from underground storage in alluvium could supplement water from surface storage in some areas. A few thousand acre-feet of water per square mile are in storage in some of the alluvium. The use of both surface and underground storage would reduce the need for additional surface-storage facilities and also would alleviate drainage problems in the irrigated areas.
Water Supply Paper↗
Availability and quality of ground water, southern Ute Indian Reservation, southwestern Colorado
Population growth and the potential development of subsurface mineral resources have increased the need for information on the availability and quality of ground water on the Southern Ute Indian Reservation. The U.S. Geological Survey, in cooperation with the Southern Ute Tribal Council, the Four Corners Regional Planning Commission, and the U.S. Bureau of Indian Affairs, conducted a study during 1974-76 to assess the ground-water resources of the reservation. Water occurs in aquifers in the Dakota Sandstone, Mancos Shale, Mesaverde Group, Lewis Shale, Pictured Cliffs Sandstone, Fruitland Formation, Kirtland Shale, Animas and San Jose Formations, and terrace and flood-plain deposits. Well yields from sandstone and shale aquifers are small, generally in the range from 1 to 10 gallons per minute with maximum reported yields of 75 gallons per minute. Well yields from terrace deposits generally range from 5 to 10 gallons per minute with maximum yields of 50 gallons per minute. Well yields from flood-plain deposits are as much as 25 gallons per minute but average 10 gallons per minute. Water quality in aquifers depends in part on rock type. Water from sandstone, terrace, and flood-plain aquifers is predominantly a calcium bicarbonate type, whereas water from shale aquifers is predominantly a sodium bicarbonate type. Water from rocks containing interbeds of coal or carbonaceous shales may be either a calcium or sodium sulfate type. Dissolved-solids concentrations of ground water ranged from 115 to 7,130 milligrams per liter. Water from bedrock aquifers is the most mineralized, while water from terrace and flood-plain aquifers is the least mineralized. In many water samples collected from bedrock, terrace, and flood-plain aquifers, the concentrations of arsenic, chloride, dissolved solids, fluoride, iron, manganese, nitrate, selenium, and sulfate exceeded U.S. Public Health Service (1962) recommended limits for drinking water. Selenium in the ground water in excess of U.S. Public Health Service (1962) recommended limit of 10 micrograms per liter for drinking water occurs throughout the reservation but principally in the central part. Of the 265 wells and springs sampled, 74 contained water with selenium concentrations in excess of the recommended limit. Selenium concentrations exceeded 10 micrograms per liter principally in water from aquifers in the San Jose and Animas Formations. The maximum selenium concentration determined during the study was 13,000 micrograms per liter in a sample obtained from the San Jose Formation. The only known documented case of human selenium poisoning caused by drinking ground water occurred on the reservation.
Water Supply Paper↗
Ground-water geology and pump irrigation in Frenchman Creek Basin above Palisade, Nebraska
This report describes the geography, geology, and ground-water resources of that part of the Frenchman Creek basin upstream from Palisade, Nebr., an area of about 4,900 square miles. The basin includes all of Phillips County, Colo., and Chase County, Nebr., and parts of Logan, Sedgwick, Washington, and Yuma Counties, Colo., and Dundy, Hayes, Hitchcock, and Perkins Counties, Nebr. The land surface ranges from nearly flat to rolling; choppy hills and interdune saddles are common in the areas of dune sand, and steep bluffs and gullies cut the edges of the relatively flat loess plateaus. Most of the basin is drained by tributaries of Frenchman Creek, but parts of the sandhills are undrained. Farming and livestock raising are the principal industries. Irrigation with ground water has expanded rapidly since 1934. The rocks exposed in the basin are largely unconsolidated and range in age from Pliocene to Recent. They comprise the Ogallala formation (Pliocene), the Sanborn formation (Pleistocene and Recent?), dune sand (Pleistocene and Recent), and alluvium (Recent). The rocks underlying the Ogallala are the Pierre shale (Late Cretaceous) and the White River group (Oligocene). The Pierre shale is relatively impermeable and yields little or no water to wells. The White River group also is relatively impermeable and yields little or no water to wells; however, small to moderate quantities of water possibly may be obtained from wells that penetrate fractured or 'porous' zones in the upper part of the White River group or permeable channel deposits within the group. The Ogallala formation is the main aquifer in the basin and yields moderate to large quantities of water to wells. The Sanborn formation and the dune sand generally lie above the water table, but in areas of high water table the dune sand yields small quantities of water to wells for domestic and stock supplies. The alluvium, which includes the low terrace deposits bordering the major streams, yields small to large quantities of water to wells. The ground-water reservoir is recharged only from precipitation on the basin. Of the average annual precipitation of 19.5 inches, about 0.9 inch infiltrates to the water table, thereby contributing about 220,000 acre-feet of water annually to the ground-water reservoir. About 81 million acre-feet of water that could drain under gravity, and thus theoretically is available to wells, is held in groundwater storage in the basin. Water is discharged from the ground-water reservoir by wells, evaporation and transpiration, springs, seepage into streams, and movement into adjacent areas to the east and southeast. Most of the domestic, stock, and irrigation water supplies and all the public supplies are pumped from wells. During 1953, 96 wells were used to irrigate 10,000 acres of land with 19,000 acre-feet of water. About 34,000 acre-feet of water is evaporated and transpired annually in the valleys of the main streams and in areas of shallow water table in the sandhills. From the projection of base-flow measurements made during 1952, it was estimated that the average annual flow of Frenchman Creek into the reservoir above Enders Dam is about 57,000 acre-feet. By similar determinations, the average annual flow of Frenchman Creek at the gaging station at Palisade, Nebr., about 22 miles downstream from Enders Dam, is about 76,000 acre-feet, and the flow of Stinking Water Creek at the gaging station near Palisade is about 22,000 acre-feet. The combined flow of Frenchman and Stinking Water Creeks at their confluence near Palisade thus is about 98,000 acre-feet per year. About 90,000 acre-feet of ground water is estimated to move eastward each year across the Colorado-Nebraska State line within the basin. Additional irrigation wells that will tap the Ogallala formation and the alluvium in the major valleys undoubtedly will be drilled. On the basis of current estimates of future irrigation.withdrawals, it is concluded that by the
Water Supply Paper↗
Geology and ground-water resources of the Bristol-Plainville-Southington area, Connecticut
The Bristol-Plainville-Southington area straddles the boundary between the New England Upland and the Connecticut Valley Lowland sections of the New England physiographic province. The western parts of Bristol are Southington lie in the New England Upland section, an area of rugged topography underlain by metamorphic rocks of Palezoic age. The eastern part of the area, to the east of a prominent scarp marking the limit of the metamorphic rocks, is in the Connecticut Valley Lowland and is underlain by sedimentary rocks and interbedded basaltic lava flows of Triassic age. The lowland is characterized for the most part by broad valleys and low intervening linear hills, but in the eastern parts of Plainville and Southington, basaltic rocks form a rugged highland. The bedrock is largely mantled by glacial deposits of Wisconsin age. On hills the glacial deposits are mainly ground moraine, and in valleys mainly stratified. The metamorphic rocks comprise the Hartland Formation, Bristol Granite Gneiss of Gregory (1906), and Prospect Gneiss. These formations contain water in fractures, principally joints occurring in regular sets. The rocks generally yield supplies of 5 to 15 gpm (gallons per minute) to drilled wells averaging about 140 feet in depth. The rocks of Triassic age in the area are the New Haven Arkose, Talcott Basalt, Shuttle Meadow Formation, Holyoke Basalt, and East Berlin Formation. The formations contain water principally in joints and other fractures and, to a lesser extent, in bedding-plane openings and pore spaces. Drilled wells penetrating these rocks generally range from 100 to 200 feet in depth and yield an average of nearly 20 gpm. The maximum yield obtained from a well in these rocks is 180 gpm. The ground moraine of Pleistocene age is composed principally of till. The deposit averages about 24 feet in thickness, and wells penetrating it average about 16 feet in depth. The ground moraine yields small supplier of water suitable for household use when tapped by shallow large-diameter wells. The stratified glacial deposits, which are as much as 300 feet thick, comprise ice-contact and proglacial deposits and deposits of generally obscure origin termed 'undifferentiated stratified deposits.' The ice-contact and undifferentiated stratified deposits, some of which underlie proglacial deposits, are coarse grained and contain gravel beds from which supplies of as much as 1,400 gpm can be obtained. The proglacial deposits are, on the whole, finer grained than the other stratified deposits, but in places they allow development of wells producing as much as 500 gpm. However, the stratified glacial deposits throughout much of the Bristol-Plainville-Southington area are fine grained and provide only small supplies.
Connecticut↗
Progress report on the ground-water resources of the Louisville area, Kentucky, 1949-55
In the Louisville area, the principal water-bearing formations are the glacial-outwash sand and gravel and, in places, the underlying limestone. During the period 1949 through 1955 pumpage from the two aquifers averaged about 30 mgd (million gallons per day). The pumpage was approximately in balance with the normal net recharge to the area but was only about 8 percent of the estimated potential supply of ground water, including induced infiltration from the river. In the Louisville area, ground water is used chiefly for air conditioning and for industrial cooling. In the part of the area southwest of the city, ground water is used also for public supply. High ground-water levels in 1937 resulted from the greatest flood of record. Subsequently, water levels generally declined in the entire Louisville area. In downtown Louisville, where ground water is used for air conditioning, the water level fluctuates seasonally in response to variations in the rate of pumping. In the heavily pumped industrial areas, where ground water is used for cooling, water-level fluctuations correlate with changes in rates of pumping caused by variations in production schedules. Levels were lowest during the years of World War II. During the period 1952-55, relatively low levels throughout the area reflected the effects of less than normal rainfall, summer drought, and sustained pumping. Ground water in the Louisville area is very hard and generally of the calcium bicarbonate or calcium sulfate type. It is high in iron and sulfate content but is moderately low in chloride content. In water of the sand and gravel aquifer, the concentration of sulfate has increased gradually during the period 1949-54.
Water Supply Paper↗
Preliminary report on the geology and underground waters of the Roswell artesian area, New Mexico
No abstract available.
New Mexico↗
Evolution of methods for evaluating the occurrence of floods
A brief summary is given of the history of methods of expressing flood potentialities, proceeding from simple flood formulas to statistical methods of flood-frequency analysis on a regional basis. Current techniques are described and evaluated. Long-term flood records in the United States show no justification for the adoption of a single type of theoretical distribution of floods. The significance and predictive values of flood-frequency relations are considered. Because of the length of flood records available and the interdependence of flood events within a region, the probable long-term average magnitudes of floods of a given recurrence interval are uncertain. However, if the magnitudes defined by the records available are accepted, the relative effects of drainage-basin characteristics and climatic variables can be determined with a reasonable degree of assurance.
Water Supply Paper↗
Factors influencing the occurrence of floods in a humid region of diverse terrain
This report describes relations between flood peaks and hydrologic factors in a humid region with limited climatic variation but a diversity of terrain. Statistical multiple-regression techniques have been applied to hydrologic data on New England. Many topographic and climatic factors have been evaluated. and their relations to flood peaks have been examined. Many of the factors that influence flood peaks are interrelated, and part of the investigation consisted of determining the most efficient factor in each of several groups of highly interrelated variables. Drainage area size was found to be the most important factor. Main-channel slope was found to be next in importance, and a simple yet efficient indicator of main-channel slope was developed. The surface area of lakes and ponds was found to be a factor significantly influencing peak discharges. Of several indices tested the intensity of rainfall for a given duration and frequency was found to be most highly related to the magnitude of peaks. The increase in peaks caused by snowmelt and frozen ground was found to be related to an index of winter temperature-the average number of degrees below freezing in January. After the above-mentioned topographic and climatic characteristics had been taken into account, there remained deviations in peak discharges that showed an evident relation to orographic patterns. An orographic factor was mapped as defined by the peak discharges of record. Multiple-regression equations were developed that related, with acceptable accuracy, peak discharges of 1.2-to 300-year recurrence intervals to 6 hydrologic variables; 3 of the variables were topographic, 2 climatic, and 1 orographic. The remaining unexplained variations in flood-peak occurrence are believed attributable to the chance variation in storms.
Water Supply Paper↗
Effect of reservoir storage on peak flow
For observation of small-basin flood peaks, numerous crest-stage gages now are operated at culverts in roadway embankments. To the extent that they obstruct the natural flood plains of the streams, these embankments serve to create detention reservoirs, and thus to reduce the magnitude of observed peak flows. Hence, it is desirable to obtain a factor, I/O, by which the observed outflow peaks may be adjusted to corresponding inflow peaks. The problem is made more difficult by the fact that, at most of these observation sites, only peak stages and discharges are observed, and complete hydrographs are not available. It is postulated that the inflow hydrographs may be described in terms of Q, the instantaneous discharge; A, the size of drainage area; Pe, the amount of rainfall excess; H, the time from beginning of rainfall excess; D, the duration of rainfall excess; and T and k, characteristic times for the drainage area, and indicative of the time lag between rainfall and runoff. These factors are combined into the dimensionless ratios (QT/APe), (H/T), (k/T), and (D/T), leading to families of inflow hydrographs in which the first ratio is the ordinate, the second is the abscissa, and the third and fourth are distinguishing parameters. Sixteen dimensionless inflow hydrographs have been routed through reservoir storage to obtain 139 corresponding outflow hydrographs. In most of the routings it has been assumed that the storage-outflow relation is linear; that is, that storage is some constant, K, times the outflow. The existence of nonlinear storage is recognized, and exploratory nonlinear routings are described, but analyses and conclusions are confined to the problems of linear storage. Comparisons between inflow hydrographs and outflow hydrographs indicate that, at least for linear storage, I/O=f(k/T, D/T, K/T) in which I and O are, respectively, the magnitudes of the inflow and the outflow peaks, and T, k, D, and K are as defined above. Diagrams are presented to show the functional relation indicated by the foregoing equation.
Water Supply Paper↗
Factors affecting the occurrence of floods in the Southwest
Explore the source record for details and available documents.
Water Supply Paper↗
A comparison of methods used in flood-frequency studies for coastal basins in California
Explore the source record for details and available documents.
Water Supply Paper↗
Ground-water potentialities in the Crescent Valley, Eureka and Lander Counties, Nevada
The Crescent Valley is an intermontane basin in Eureka and Lander Counties, just south of the Humboldt River in north-central Nevada. The valley floor, with an area of about 150 square miles, has a shape that more nearly resembles a Y than a crescent, although the valley apparently was named after the arc described by its southern part and northeastern arm. The northwestern arm of the Y extends northward to the small railroad town of Beowawe on the Humboldt River; the northeastern arm lies east of the low Dry Hills. The leg of the Y extends southwestward toward a narrow gap which separates the Crescent Valley from the Carico Lake Valley. The total drainage area of the Crescent Valley-about 700 square miles--includes also the slopes of the bordering mountain ranges: the Shoshone Range to the west, the Cortez Mountains to the east, and the Toiyabe Range to the south. The early history of the Crescent Valley was dominated by mining of silver and gold, centered at Lander in the Shoshone Range and at Cortez and Mill Canyon in the Cortez Mountains, but in recent years the only major mining activity has been at Gold Acres; there open-pit mining of low-grade gold ore has supported a community of about 200. For many years the only agricultural enterprises in the valley were two cattle ranches, but recently addition lands have been developed for the raising of crops in the west-central part of the valley. The average annual precipitation upon the floor of the Crescent Valley is probably less than 7 inches, of which only a little more than 1 inch formally falls during the growing season (from June through September). This is far less than the requirement of any plants of economic value, and irrigation is essential to agricultural development. Small perennial streams rising in the mountains have long been utilized for domestic supply, mining and milling activities of the past, and irrigation, and recently some large wells have been developed for irrigation. In 1956 the total pumpage from wells in the valley was 2,300 acre-feet. The Crescent Valley is a basin in which has accumulated a large volume of sediments that had been eroded and transported by streams from the surrounding mountains. The deepest wells have penetrated only the upper 350 feet of these sediments, which on the basis of the known thickness of sediments in other intermontane basins in central Nevada may be as much as several thousand feet thick. Because this valley fill is saturated practically to the level of the valley floor, the total volume of ground water in storage amounts to millions of acre-feet. In practically all wells drilled to date, the water has been of a quality satisfactory for irrigation and domestic use. The amount of water that can be developed and used perennially is far smaller than the total in storage and is dependent upon the average annual recharge to the ground-water reservoir. This recharge comes principally from streams, fed largely by snowmelt, that drain the higher mountains. The average annum recharge to the valley fill is estimated to be about 13,000 acre-feet. This natural supply, which is largely consumed by native vegetation on the valley floor, constitutes a perennial supply for beneficial use only to the extent that the natural discharge can be reduced. In time, much of the natural discharge, can probably be salvaged, if it is economically feasible to pump ground water after water levels have been lowered as much as 100 feet in the areas that now appear to be favorable for the development of irrigation supplies. In 5 wells in the phreatophyte area, where the water table is within 3-8 feet of the land surface, the trends in water level have paralleled those, in precipitation-downward during the dry years 1952-55, upward in wetter 1956 and 1957, and as high in 1957 as at any time since 1948. In most wells there is also a seasonal fluctuation of 1-3 feet, from a high in the spring to a low in the fall. There is no evi
Water Supply Paper↗
Geology and ground-water resources of Winkler County, Texas
Winkler County, in west Texas, is adjacent to the southeast corner of New Mexico. Most of the county lies in the Pecos Valley; the remainder, in the northeastern part of the county, is part of the Llano Estacado, or the High Plains. Its principal industries are those related to the production and refining of oil, but ranching also is an important occupation. The county has an arid to semiarid climate, an area of about 887 square miles, and a population of about 12,000 in 1957. The principal fresh-water-bearing formations in Winkler County are the Cenozoic alluvium, which mantles the surface of most of the county, and the Santn Rosa sandstone of Late Triassic age. The alluvium is saturated at a depth ranging from a few feet below the land surface to about 150 feet, and the water is under water-table conditions. The Santa Rosa sandstone is fully saturated throughout most of the county, the water occurring under both unconfined (water-table) and confined (artesian) conditions. The underlying older formations contain water too highly mineralized for most uses, but they are important because water from these underlying beds, which is produced with the oil, is a source of pollution to the fresh-water aquifers. The formations also are a source of water to waterflooding projects for the secondary recovery of oil. The alluvium is replenished chiefly by precipitation, throughout the county. The sand-dune area in the eastern part is the most favorable area of natural recharge. The Santa Rosa sandstone is recharged through the alluvium where the two formations are in contact. Infiltration of saline water, which with oil and waste water has been produced from industrial plants, has been taking place through surface earthen pits. About 18 mgd (million gallons per day) of saline water was being produced from the many oil fields throughout the county during August 1957, and almost all this water was placed in surface pits. The Hendrick oil field alone produced about 14.5 mgd during that month, and an estimated 800,000 acre-feet from 1937 to 1957. About 20 million acre-feet of fresh water is stored in the explored groundwater aquifers of Winkler County, of which an estimated 5 to 7 million acrefeet can be practicably recovered. A daily average of about 8.2 million gallons (9,200 acre-feet per year) of fresh water was used in the county during 1956. Public and industrial use accounted for about 6.8 mgd; irrigation, domestic, and stock uses accounted for 1.4 mgd. Projects engaged in the secondary recovery of oil were the largest consumers, using an average of about 3 mgd of fresh water and about 2.7 mgd of saline water during 1956. Water wells drilled in the deep trough of Cenozoic alluvium south of Wink may yield 1,000 gpm (gallons per minute) or more. A pumping test of the alluvium in that area indicated a coefficient of transmissibility of about 25,000 gpd (gallons per day) per foot. Wells, other than windmill wells, drawing water from thinner sections of alluvium in the rest of the county yield between 100 and 300 gpm. Most of the wells in the Santa Rosa sandstone yield 30-400 gpm. Two municipal wells at Kermit that tap the Santa Rosa sandstone were tested at 1,200 and 1,875 gpm. The large yield of these wells probably results from the presence of fractures in the structurally deformed aquifer. Pumping tests in the Kermit area indicate that locally a full section of the Santa Rosa sandstone has an average coefficient of transmissibility of about 25,000 gpd per foot and a coefficient of storage of about 0.0003. The transmissibility in two other tested areas is much less. The chemical quality of the water in the principal aquifers is generally acceptable for industry and for public supply. About two-thirds of the samples collected from fresh-water wells had a dissolved-solids content of less than 1,000 ppm (parts per million) ; however, some samples in a few areas were hard and were high in fluoride and silica. Samples from wells in polluted areas contained dissolved solids ranging from about 1,400 to 71,100 ppm. Two comprehensive analyses of water samples from the Rustler formation showed a dissolved-solids content of 18,400 ppm. and 157,000 ppm. In most of the water produced with the oil in the Hendrick oil field, the content of dissolved solids ranged from about 4,000 to about 10,000 ppm. The water produced with the oil in the rest of the oil fields in Winkler County was mainly brine.
Water Supply Paper↗
Ground water in Fountain and Jimmy Camp Valleys, El Paso County, Colorado
The part of Fountain Valley considered in this report extends from Colorado Springs to the Pueblo County line. It is 23 miles long and has an area of 26 square miles. The part of Jimmy Camp Valley discussed is 11 miles long and has an area of 9 square miles. The topography is characterized by level flood plains and alluvial terraces that parallel the valley and by rather steep hills along the valley sides. The climate is semiarid, average annual precipitation being about 13 inches. Farming and stock raising are the principal occupations in the valleys; however, some of the agricultural land near Colorado Springs is being used for housing developments. The Pierre Shale and alluvium underlie most of the area, and mesa gravel caps the shale hills adjacent to Fountain Valley. The alluvium yields water to domestic, stock, irrigation, and public-supply wells and is capable of yielding large quantities of water for intermittent periods. Several springs issue along the sides of the valley at the contact of the mesa gravel and the underlying Pierre Shale. The water table ranges in depth from less than 10 feet along the bottom lands to about 80 feet along the sides of the valleys; the saturated thickness ranges from less than a foot to about 50 feet. The ground-water reservoir in Fountain Valley is recharged by precipitation that falls within the area, by percolation from Fountain Creek, which originates in the Pikes Peak, Monument Valley, and Rampart Range areas, and by seepage from irrigation water. This reservoir contains about 70,000 acre-feet of ground water in storage. The ground-water reservoir in Jimmy Camp Valley is recharged from precipitation that falls within the area, by percolation from Jimmy Camp Creek during periods of streamflow, and by seepage from irrigation water. The Jimmy Camp ground-water reservoir contains about 25,000 acre-feet of water in storage. Ground water is discharged from the area by movement to the south, by evaporation and transpiration in areas of shallow water table, by seepage into Fountain and Jimmy Camp Creeks, and through wells. About 3 to 4 mgd (million gallons per day) of ground water moves through the Fountain Valley alluvium at a velocity of about 15 feet per day. About 1 mgd of ground water moves through the Jimmy Camp Valley alluvium at a velocity of about 6 feet per day. Most of the wells in the area are drilled, but a few are dug. Many large-diameter wells are used for irrigation and public supply: one of the wells
Colorado↗
Geology and ground-water resources of Uvalde County, Texas
The principal aquifer in Uvalde County is the Edwards and associated limestones of Cretaceous age. The aquifer underlies an extensive area in south-central Texas extending along the Balcones fault zone from Kinney County eastward to San Antonio, and thence northeastward to Hays County. The hydrologic unit making up the Edwards and associated limestones consists of the Comanche Peak limestone, the Edwards limestone, the Kiamichi formation, and the Georgetown limestone. Other less important aquifers in Uvalde County include the Glen Rose limestone, the Buda limestone, the Austin chalk, and the Leona formation. Uvalde County occupies parts of two physiographic provinces, the Edwards Plateau on the north and the Coastal Plain on the south; the two provinces are separated by the Balcones fault zone. In the Edwards Plateau the formations of the Edwards and associated limestones crop out on the plateau surface; in the Coastal Plain where the formations have been down-faulted, they underlie younger rocks. In both provinces the formations dip gently toward the south and southeast; the dips are greatest in the Coastal Plain. Igneous intrusions have penetrated the formations in many places in the Coastal Plain, and locally have formed barriers to ground-water movement. The aquifers in Uvalde County are recharged by precipitation within the county and in the drainage areas of streams entering the county from the north and west. In the Edwards Plateau, the Edwards and associated limestones are recharged by precipitation that falls on the outcrop. The aquifer is drained by springs at the contact with the underlying Glen Rose limestone where streams have cut through the Edwards at the edge of the plateau. These springs maintain the base flow of the streams that drain the plateau. Most of the base flow and much of flood flow of the streams is lost to the Edwards and associated limestones where they crop out in streambeds in the Balcones fault zone. This stream loss to the aquifer constitutes the greatest part of the recharge in the county, although some of the recharge from the West Nueces River enters the county as underflow from Kinney County. The normal annual recharge to the Edwards in Uvalde County is estimated to be about 200,000 acre-feet. Discharge from the Edwards and associated limestones in Uvalde County can be divided into two .major segments: discharge by underflow from the county to the east and south and discharge to the surface through wells and springs. Discharge by underflow during the period 1934-47, when changes in storage were small, is estimated to have been about 190,000 acre-feet per year. During the drought years 1947-56 the underflow was somewhat less. The discharge to the surface during 1934-47 averaged about 17,000 acre-feet per year. During the 1947-56 drought the rate of discharge to the surface increased principally because of increased use of water for irrigation, reaching a maximum of 58,000 acre-feet in 1956. The chemical quality. of the ground water in Uvalde County ranges between wide limits. Except in the extreme southern part of the county where the water is saline, the water in the Edwards and associated limestones is of good chemical quality except that it is hard. The water in the Glen Rose limestone is saline in many places; the principal objectionable constituents are high concentrations of calcium and magnesium sulfate. The water in the Leona formation is generally of good chemical quality. The water from the other formations varies widely in quality from place to place and no generalizations can be made. Ground-water withdrawals from the Edwards and associated limestones in Uvalde County probably could be maintained indefinitely at a rate of about 200,000 acre-feet per year, provided that withdrawals north and west of the county were not increased. However, continued withdrawals at this rate-would cause wells in structurally high areas to go dry, and underflow into Medina County would cease. Furthermore, saline water might invade the fresh-water part of the aquifer from the south, and perennial spring flow in the Leona River valley would cease.
Texas↗
Effect of irrigation on ground water in southern Canyon County, Idaho
Explore the source record for details and available documents.
Water Supply Paper↗
Water quality and hydrology in the Fort Belvoir area, Virginia, 1954-55
This report summarizes the results of an investigation of water quality and hydrology in the Fort Belvoir, Va., area for the period August 1954 to September 1955. It summarizes and evaluates information about the water resources of this area that are pertinent to the choice of location and operation of an Army nuclear power reactor. The quantity, quality, nature, and use of the local water that might be affected by the location and operation of a reactor in the area were subjects of investigation. Variations in the quality of the water caused by variation in streamflow, tidal effects, and pollution were important facets of the investigation. During extended periods of low streamflow in the Potomac River (usually in the late summer months), salty water moves upstream from Chesapeake Bay and increases the dissolved solids content of the surface waters adjacent to Fort Belvoir. When the streamflow is low the concentration of dissolved solids in the water near the river bottom exceeds that near the surface. The waters in Gunston Cove usually contain more dissolved oxygen than those in the Potomac River. During the summer, the content of dissolved oxygen in the cove waters frequently exceeds 100 percent of saturation. Surface floats that were released on a flood tide in Gunston Cove moved toward the inner portion of the cove in the same direction as the wind and the tide. The maximum average velocity of these floats was 0.65 feet per second. On an ebb tide, many surface floats that were released in Gunston Cove moved toward the inner portion of the cove in the direction of the wind, in opposition to the direction of the tidal movement. Floats released near the mouth of the cove on the same tide, moved with the tide out of the cove through a narrow pass at the end of a submerged sandbar extending from the Fort Belvoir shoreline. The maximum average velocity of the floats in the pass on this ebb tide was 0.85 feet per second. Measurements of subsurface flow direction indicate that the water in the deeper part of Gunston Cove tended to move toward Accotink Bay on the flood tide and out of the cove into the Potomac River on the ebb tide. The water 150-500 feet offshore from the reactor site tended to move toward Accotink Bay on the flood tide and toward Pohick Bay on the ebb tide, whereas waters 30 feet from the Fort Belvoir shoreline tended to move counterclockwise during part of the time. In Gunston Cove the maximum measured flood velocity was 0.48 feet-per second, and the maximum ebb velocity was 0.71 per second. During periods of low streamflow, pollutants that enter the Potomac River at Fort Belvoir may move as much as 5.5 miles upstream on a flood tide and as much as 5 miles downstream on an ebb tide. At higher flow rates movement of pollutants is less upstream and greater downstream. The time required to flush the 10-mile reach of the Potomac River adjacent to Fort Belvoir varies from a day or two at high-flow rates to several weeks at low-flow rates.
Water Supply Paper↗