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E.L. Bolke

Publications and source records attributed to E.L. Bolke.

At least 19 recordsLinked to original sources
USGS1998

Numerical analysis of the hydrogeologic controls in a layered coastal aquifer system, Oahu, Hawaii, USA

The coastal aquifer system of southern Oahu, Hawaii, USA, consists of highly permeable volcanic aquifers overlain by weathered volcanic rocks and interbedded marine and terrestrial sediments of both high and low permeability. The weathered volcanic rocks and sediments are collectively known as caprock, because they impede the free discharge of groundwater from the underlying volcanic aquifers. A cross-sectional groundwater flow and transport model was used to evaluate the hydrogeologic controls on the regional flow system in southwestern Oahu. Controls considered were: (a) overall caprock hydraulic conductivity; and (b) stratigraphic variations of hydraulic conductivity in the caprock. Within the caprock, variations in hydraulic conductivity, caused by stratigraphy or discontinuities of the stratigraphic units, are a major control on the direction of groundwater flow and the distribution of water levels and salinity. Results of cross-sectional modeling confirm the general groundwater flow pattern that would be expected in a layered coastal system. Groundwater flow is: (a) predominantly upward in the low-permeability sedimentary units; and (b) predominantly horizontal in the high-permeability sedimentary units.

Hydrogeology Journal↗
USGS1989

Ground-water inflow to the Deschutes River near the Warm Springs Indian Reservation, Oregon, August 1985

Groundwater inflow to the Deschutes River near the Warm Springs Indian Reservation in Oregon was estimated for August 1985 by: (1) measuring streamflow at various sites along the river; (2) determining the part of the streamflow that is groundwater inflow; and (3) analyzing the hydraulic gradients of the groundwater flow system to estimate the amount of groundwater discharge to the Deschutes River from both sides of the river. Results of the streamflow analysis indicated that the Deschutes River gained 415 cu ft/sec between Round Butte Dam and Dant in August 1985. Results of the analysis on hydraulic gradients of the groundwater flow system showed that the amount of groundwater inflow from the west side ranged from about 207 to 216 cu ft/sec, and groundwater inflow from the east side ranged from about 199 to 207 cu ft/sec. Streamflow measurements in September 1985 along the Metolius River from the site above Jefferson creek to the site below Camp Creek indicated a gain of 70 cu ft/sec. From the site below Camp Creek to the gage above Lake Billy Chinook the results of discharge measurements showed a loss of 112 cu ft/sec. Because of lack of groundwater hydraulic-head and lithologic data, no analysis of the groundwater flow system near the Metolius River was attempted. (USGS)

Water-Resources Investigations Report↗
USGS1988

U.S. Geological Survey ground-water studies in Oregon

The use of groundwater in Oregon is expected to increase owing to continued population growth and to surface water supplies that are inadequate to meet present or future demand. The major groundwater issues in Oregon are: conjunctive use of surface and groundwater; contamination from hazardous wastes, leakage from underground gasoline and diesel tanks, naturally occurring brackish water, and high concentrations of dissolved iron; groundwater availability; and Indian water rights. Before 1987, the Oregon Water Resources Department, in cooperation with the U.S. Geological Survey (USGS), maintained a network of about 400 observation wells in Oregon to monitor fluctuations in groundwater levels. Water levels currently are measured cooperatively only in active project areas. The USGS has conducted more than 120 hydrologic investigations in Oregon. During fiscal year 1987, the USGS entered into cooperative agreements with 23 local, State, and Federal agencies to conduct hydrologic investigations in Oregon; six investigations included quantitative studies of groundwater. Examples of these groundwater studies are: groundwater hydrology of the Portland basin; groundwater hydrology in the Umatilla Plateau; and iron geochemistry of a sand dune aquifer near Coos Bay. (Lantz-PTT)

Open-File Report↗
USGS1988

Geohydrology and digital simulation of the ground-water flow system in the Umatilla Plateau and Horse Heaven Hills area, Oregon and Washington

The Columbia Plateau is underlain by massive basalt flows, with a composite thickness of about 10,000 ft. Structural features within the study area include a series of anticline-syncline pairs. The main avenues of groundwater movement in the basalt are the interflow zone between basalt flows. Individual interflow zones may be rather extensive in the lateral direction and are largely isolated from overlying and underlying interflows by poorly permeable basalt flow centers. Four aquifers were defined for this study. The uppermost aquifer (layer 1) consists of unconsolidated deposits of gravel, sand, silt, and clay that overlie the basalt: layer 2 consists of the Saddle Mountains Basalt, layer 3 the Wanapum Basalt, and layer 4 consists of the upper thousand ft of Grande Ronde Basalt. Recharge to the groundwater system is from precipitation, leakage from streams, and seepage from surface water irrigation. Natural discharge of aquifers is principally to streams. Discharge by groundwater pumpage from the study area ranged from approximately 2,000 acre-ft in 1950 to 144,000 acre-ft in 1980. About 85% of the total pumpage in 1980 was from the Oregon part of the study area. Water level declines of over 300 ft occur locally in parts of the study area. (USGS)

Water-Resources Investigations Report↗
USGS1983

Evaluation of water-quality characteristics of part of the Spokane Aquifer, Washington and Idaho, using a solute-transport digital model

The principal dissolved constituents in water in the Spokane aquifer are calcium and bicarbonate. These constituents (as well as dissolved solids, hardness, and magnesium) each correlate well with specific conductance, whereas chloride, sodium, and nitrate each do not. Specific conductance ranges from 73 to 820 micromhos per centimeter throughout the study area. Short-term variations in water quality in the Spokane aquifer are generally greater than long-term variations. Vertical variations in concentration of chemical constituents occurred in four of 15 wells used to sample the upper 50 feet of the aquifer along several cross sections. Changes in water quality from one cross section to another could not be directly related to land-use activities. A digital model was developed and used to simulate solute transport of conservative ions in the Spokane aquifer. Specifically, the model was used to estimate the impact of the chloride ion from recharge through septic tanks and from irrigation on the water quality of the aquifer. Analysis shows that the estimated impact on the aquifer from these two source loadings was less than a 1-milligram-per-liter increase throughout approximately 80 percent of the aquifer, but increases averaging about 3 milligrams per liter occurred in some peripheral areas. Various water-quality-management schemes based on manmade or natural stresses can be tested with the model.

Open-File Report↗
USGS1981

Digital-model simulation of the Toppenish alluvial aquifer, Yakima Indian Reservation, Washington

Increasing demands for irrigating additional lands and proposals to divert water from the Yakima River by water users downstream from the Yakima Indian Reservation have made an accounting of water availability important for present-day water management in the Toppenish Creek basin. A digital model was constructed and calibrated for the Toppenish alluvial aquifer to help fulfill this need. The average difference between observed and model-calculated aquifer heads was about 4 feet. Results of model analysis show that the net gain from the Yakima River to the aquifer is 90 cubic feet per second, and the net loss from the aquifer to Toppenish Creek is 137 cubic feet per second. Water-level declines of about 5 feet were calculated for an area near Toppenish in response to a hypothetical tenfold increase in 1974 pumping rates.

Washington↗
USGS1980

Ground-water availability on the Kitsap Peninsula, Washington

Unconsolidated deposits on the Kitsap peninsula are of glacial and interglacial origin. These deposits were divided into three units on the basis of their lithology and hydraulic properties. Two of the three units are composed of layers of sand and gravel alternating with layers of silt and clay. The third unit consists of silt and clay and in most places separates the other two units. The thickness of the upper unit ranges from 200 to 600 feet and the middle unit from 10 to 260 feet. The thickness of the lower unit is believed to range from 2,000 to 3,000 feet. The water-bearing strata in the upper unit are fairly continuous and average 15 feet in thickness. The lower water-bearing strata probably are not as continuous as those in the upper unit, but they yield larger quantities of water to wells. The silt-and-clay unit averages 70 feet in thickness, occurs generally near sea level, and is not known to contain any major water-bearing deposits. The average annual ground-water recharge to streams on the Kitsap peninsula was estimated to be 17 times the 1975 annual ground-water pumpage for the peninsula. Some, hut an unknown amount, of this water is available for increased withdrawal by wells. Increased withdrawals cause decreased streamflow, declining water levels, and increased seawater contamination. There appears to be no widespread seawater contamination of wells in the study area. Local areas where chloride concentrations in well water exceed 25 milligrams per liter are the southern part of the Longbranch peninsula, Horsehead Bay, Point Evans, Sinclair Inlet, Eagle Harbor, Fletcher Bay, the north end of Bainbridge Island, and the north tip of the Kitsap peninsula.

Washington↗
USGS1980

Digital model simulation of the hydrologic flow system, with emphasis on ground water in Spokane Valley, Washington and Idaho

A digital-computer model of the hydrologic flow system, with emphasis on ground water, was developed for Spokane Valley, Washington and Idaho. The current rate of ground-water pumping in Spokane Valley has little effect on water levels in the Spokane aquifer, although short-term water-level declines occur locally. The model was used to show the effects of increased ground-water pumpage on aquifer heads and streamflow. A simulated pumping rate twice that of actual 1977 pumping rates of 227 cubic feet per second lowered water levels in the Spokane aquifer less than 3 feet during a 1-year simulation period. This doubling of the ground water pumpage caused a decrease in discharge of the Spokane River, as measured at Spokane, of about 150 cubic feet per second during the summer months and about 50 cubic feet per second during the rest of the year. Leakage from the aquifer to the Little Spokane River was decreased by less than 10 cubic feet per second.

Idaho, Washington↗
USGS1979

Selected hydrologic data for Spokane Valley, Spokane, Washington 1977-78

This report presents the ground-water data collected from March 1977 to May 1978 in the Spokane Valley, Spokane, Washington, for the purpose of developing a computer simulation of flow and mass transport in the Spokane aquifer. Data collected include an inventory of wells and springs, water-level data, and chemical analyses of water from selected wells and springs. (Kosco-USGS)

Open-File Report↗
USGS1979

Dissolved-oxygen depletion and other effects of storing water in Flaming Gorge Reservoir, Wyoming and Utah

The circulation of water in Flaming Gorge Reservoir is caused chiefly by insolation, inflow-outflow relationships, and wind, which is significant due to the geographical location of the reservoir. During 1970-75, there was little annual variation in the thickness, dissolved oxygen, and specific conductance of the hypolimnion near Flaming Gorge Dam. Depletion of dissolved oxygen occurred simultaneously in the bottom waters of both tributary arms in the upstream part of the reservoir and was due to reservoir stratification. Anaerobic conditions in the bottom water during summer stratification eventually results in a metalimnetic oxygen minimum in the reservoir. The depletion of flow in the river below Flaming Gorge Dam due to evaporation and bank storage in the reservoir for the 1963-75 period was 1,320 cubic hectometers, and the increase of dissolved-solids load in the river was 1,947,000 metric tons. The largest annual variations in dissolved-solids concentration in the river was about 600 milligrams per liter before closure of the dam and about 200 milligrams per liter after closure. The discharge weighted-average dissolved-solids concentration for the 5 years prior to closure was 386 milligrams per liter and 512 milligrams per liter after closure. The most significant changes in the individual dissolved-ion loads in the river during 1973-75 were the increase in sulfate (0.46 million metric tons), which was probably derived from the solution of gypsum, and the decrease in bicarbonate (0.39 million metric tons), which can be attributed to chemical precipitation. The maximum range in temperature in the Green River below the reservoir prior to closure of the dam in 1962 was from 0°C in winter to 21°C in summer. After closure until 1970 the temperature ranged from 2° to 12°C, but since 1970 the range has been from 4° to 9°C. The maximum range in temperature in the Green River below the reservoir prior to closure of the dam in 1962 was from 0°C in winter to 21°C in summer. After closure until 1970 the temperature ranged from 2° to 12°C, but since 1970 the range has been from 4° to 9°C.During September 1975, a massive algal bloom was observed in the upstream part of the reservoir. The bloom covered approximately 16 kilometers of the lower part of the Blacks Fork arm, 23 kilometers of the lower part of the Green River arm, and 15 kilometers of the main reservoir below the confluence of the two arms. By October 1975 the algal bloom had disappeared. Nutrient loading in the reservoir was not sufficient to maintain a rate of algal production that would be disastrous to the reservoir ecosystem. However, should the nutrient loading increase substantially, the quality of the reservoir water could probably deteriorate rapidly, and its use for recreation and water supply could be severely limited.

Utah, Wyoming↗
USGS1978

Hydrologic reconnaissance of the Fish Springs Flat area, Tooele, Juab and Millard counties, Utah

The Fish Springs Flat area includes about 590 square miles (1,530 square kilometers) in western Utah. Total annual precipitation on the area averages about 7 inches (180 millimeters) and totals about 232,000 acre-feet (286 cubic hectometers). Fish Springs Wash is the major drainage in the area; and, along with numerous smaller washes, it flows only in direct response to precipitation. Runoff from the area is estimated to be about 2,000 acre-feet (2.5 cubic hectometers) per year. The estimated amount of water recoverable from storage in the upper 100 feet (30 meters) of saturated valley fill is about 550,000 acre-feet (680 cubic hectometers), and most of this water is slightly to moderately saline. The water in the Fish Springs Flat area ranges from slightly saline to briny, and the predominant ions in the water are sodium and chloride. The water that underlies the mudflats in the northwest part of the area is briny. Water that issues from Fish Springs is slightly saline. The water in the Fish Springs Flat area is not suitable for drinking. The water that issues from Fish Springs is used for wildlife management, which includes ponding and irrigation of vegetation (chiefly saltgrass) in the Fish Springs National Wildlife Refuge. The water from the wells in the area is used for livestock and mining operations. Ground-water recharge from precipitation is about 4,000 acre-feet (5 cubic hectometers) annually. Ground-water discharge is chiefly by springs and evapotranspiration. The largest springs in the Fish Springs group discharge about 26,000 acre-feet (32 cubic hectometers) annually. All other springs discharge about 600 acre-feet (0.74 cubic hectometer) per year, or only about 2 percent of the total spring discharge. Discharge by evapotranspiration is about 8,000 acre-feet (10 cubic hectometers) per year. Discharge by wells and by subsurface outflow is negligible. The difference between discharge and local recharge--approximately 31,000 acre-feet (38 cubic hectometers)--is assumed to enter the Fish Springs Flat area by interbasin flow.

Utah↗
USGS1978

Dissolved-oxygen depletion and other effects of storing water in Flaming Gorge Reservoir, Wyoming and Utah

The circulation of water in Flaming Gorge Reservoir is caused chiefly by insolation, inflow-outflow relationships, and wind, which is significant due to the geographical location of the reservoir. During 1970-75, there was little annual variation in the thickness, dissolved oxygen, and specific conductance of the hypolimnion near Flaming Gorge Dam. Depletion of dissolved oxygen occurred simultaneously in the bottom waters of both tributary arms in the upstream part of the reservoir, and was due to reservoir stratification. Anaerobic conditions in the bottom water during summer stratification eventually results in a metalimnetic oxygen minimum in the reservoir.

Utah, Wyoming↗
USGS1978

Hydrologic reconnaissance of the Fish Springs Flat area, Tooele, Juab, and Millard Counties, Utah

The Fish Springs Flat area includes about 590 square miles (1,530 square kilometers) in western Utah. Total annual precipitation on the area averages about 7 inches (180 millimeters) and totals about 232,000 acre-feet (286 cubic hectometers). Fish Springs Wash is the major drainage in the area; and, along with numerous smaller washes, it flows only in direct response to precipitation. Runoff from the area is estimated to be about 2,000 acre-feet (2.5 cubic hectometers) per year.

Utah↗
USGS1977

Developing a state water plan: Ground-water conditions in Utah, spring of 1977

This report is the fourteenth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, prepared cooperatively by the U.S. Geological Survey and the Utah Division of Water Resources, provide data to enable interested parties to keep abreast of changing ground-water conditions. This report, like the others (see references, p. 16), contains information on well construction, ground-water withdrawals, water-level changes, and related changes in precipitation and streamflow. Supplementary data such as graphs showing chemical quality of water and maps showing water-table configuration are included in reports of this series only for those years or areas for which applicable data are available and are important to a discussion of changing ground-water conditions. This report includes individual discussions of selected major areas of ground-water withdrawal in the State for the calendar year 1976. Water-level fluctuations, however, are described for the period spring 1976 to spring 1977. Much of the data used in this report were collected by the U.S. Geological Survey in cooperation with the Division of Water Rights, Utah Department of Natural Resources.

Utah↗
USGS1976

Developing a state water plan: Ground-water conditions in Utah, spring of 1976

This report is the thirteenth in a series of annual reports that describe ground-water conditions in Utah. Reports in this series, prepared cooperatively by the U.S. Geological Survey and the Utah Division of Water Resources, provide data to enable interested parties to keep abreast of changing ground-water conditions. This report, like the others (see references, p. 16), contains information on well construction, ground-water withdrawals, water-level changes, and related changes in precipitation and streamflow. Supplementary data such as graphs showing chemical quality of water and maps showing water-table configuration are included in reports of this series only for those years or areas for which applicable data are available and are important to a discussion of changing ground-water conditions. This report includes individual discussions of selected major areas of ground-water withdrawal in the State for the calendar year 1975. Water-level fluctuations, however, are described for the period spring 1975 to spring 1976. Much of the data used in this report were collected by the U.S. Geological Survey in cooperation with the Division of Water Rights, Utah Department of Natural Resources.

Utah↗
USGS1976

Chemical and physical data for the Flaming Gorge Reservation area, Utah and Wyoming, 1973-75

This report presents the basic data that were collected by the U.S. Geological Survey during a study of the chemical quality of water in Flaming Gorge Reservoir. An interpretive report will follow. The basic data were collected from the reservoir during the period August 1973 to October 1975. The reservoir was sampled for chemical and physical data at 25 sites. The sites are shown in figure 1 and the data are listed in tables 1-3. In addition to the data collected from the reservoir, streamflow and water-quality data are collected on a continuing basis at sites on the major streams flowing into and out of the reservoir. The inflow sites are Green River near Green River, Wyo., Blacks Fork near Little America, Wyo., and Henrys Fork near Manila, Utah (fig. 1). The out- flow site is Green River near Greendale, Utah. These data are published in an annual series, and for the period of this project the data are in U.S. Geological Survey (197l-75a, b, c, d).

Utah, Wyoming↗