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Research about Salt Lake County, Utah

Source-linked reports with geographic coverage including Salt Lake County, Utah.

At least 19 recordsLinked to original sources

Principal locations of major-ion, trace-element, nitrate, and Escherichia coli loading to Emigration Creek, Salt Lake County, Utah, October 2005

Housing development and recreational activity in Emigration Canyon have increased substantially since 1980, perhaps causing an observed decrease in water quality of this northern Utah stream located near Salt Lake City. To identify reaches of the stream that contribute to water-quality degradation, a tracer-injection and synoptic-sampling study was done to quantify mass loading of major ions, trace elements, nitrate, and Escherichia coli (E. coli) to the stream. The resulting mass-loading profiles for major ions and trace elements indicate both geologic and anthropogenic inputs to the stream, principally from tributary and spring inflows to the stream at Brigham Fork, Burr Fork, Wagner Spring, Emigration Tunnel Spring, Blacksmith Hollow, and Killyon Canyon. The pattern of nitrate loading does not correspond to the major-ion and trace-element loading patterns. Nitrate levels in the stream did not exceed water-quality standards at the time of synoptic sampling. The majority of nitrate mass loading can be considered related to anthropogenic input, based on the field settings and trends in stable isotope ratios of nitrogen. The pattern of E. coli loading does not correspond to the major-ion, trace-element, or nitrate loading patterns. The majority of E. coli loading was related to anthropogenic sources based on field setting, but a considerable part of the loading also comes from possible animal sources in Killyon Canyon, in Perkins Flat, and in Rotary Park. In this late summer sampling, E. coli concentrations only exceeded water-quality standards in limited sections of the study reach. The mass-loading approach used in this study provides a means to design future studies and to evaluate the loading on a catchment scale.

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Quality and sources of ground water used for public supply in Salt Lake Valley, Salt Lake County, Utah, 2001

Ground water supplies about one-third of the water used by the public in Salt Lake Valley, Utah. The occurrence and distribution of natural and anthropogenic compounds in ground water used for public supply in the valley were evaluated. Water samples were collected from 31 public-supply wells in 2001 and analyzed for major ions, trace elements, radon, nutrients, dissolved organic carbon, methylene blue active substances, pesticides, and volatile organic compounds. The samples also were analyzed for the stable isotopes of water (oxygen-18 and deuterium), tritium, chlorofluorocarbons, and dissolved gases to determine recharge sources and ground-water age. Dissolved-solids concentration ranged from 157 to 1,280 milligrams per liter (mg/L) in water from the 31 public-supply wells. Comparison of dissolved-solids concentration of water sampled from the principal aquifer during 1988-92 and 1998-2002 shows a reduction in the area where water with less than 500 mg/L occurs. Nitrate concentration in water sampled from 12 of the 31 public-supply wells was higher than an estimated background level of 2 mg/L, indicating a possible human influence. At least one pesticide or pesticide degradation product was detected at a concentration much lower than drinking-water standards in water from 13 of the 31 wells sampled. Chloroform was the most frequently detected volatile organic compound (17 of 31 samples). Its widespread occurrence in deeper ground water is likely a result of the recharge of chlorinated public-supply water used to irrigate lawns and gardens in residential areas of Salt Lake Valley. Environmental tracers were used to determine the sources of recharge to the principal aquifer used for public supply in the valley. Oxygen-18 values and recharge temperatures computed from dissolved noble gases in the ground water were used to differentiate between mountain and valley recharge. Maximum recharge temperatures in the eastern part of the valley generally are below the range of valley water-table temperatures indicating that mountain-block recharge must constitute a substantial fraction of recharge to the principal aquifer in this area. Together, the recharge temperature and stable-isotope data define two zones with apparently high proportions of valley recharge on the east side of the valley. The possibility of water samples containing a substantial proportion of water recharged before thermonuclear testing began in the early 1950s (pre-bomb) was evaluated by comparing the initial tritium concentration of each sample (measured tritium plus measured tritiogenic helium-3) to that of local precipitation at the apparent time of recharge. Three interpreted-age categories were determined for water from the sampled wells: (1) dominantly pre-bomb; (2) dominantly modern; and (3) modern or a mixture of pre-bomb and modern. Apparent tritium/helium-3 ages range from 3 years to more than 50 years. Water generally becomes older with distance from the mountain front, with the oldest water present in the discharge area. The presence of anthropogenic compounds at concentrations above reporting levels and elevated nitrate concentrations (affected wells) in the principal aquifer is well correlated with the distribution of interpreted-age categories. All of the wells (10 of 10) with dominantly modern water are affected. Seventy percent (7 of 10) of the wells with dominantly modern or a mixture of modern and pre-bomb waters are affected. Only 1 of the 11 wells with dominantly pre-bomb water is affected. Anthropogenic compounds were not detected in water with an apparent age of more than 50 years, except for water from one well. All of the samples that consisted mostly of modern water contained at least one anthropogenic compound.

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Quality and sources of shallow ground water in areas of recent residential development in Salt Lake Valley, Salt Lake County, Utah

Residential and commercial development of about 80 square miles that primarily replaced undeveloped and agricultural areas occurred in Salt Lake Valley, Utah, from 1963 to 1994. This study evaluates the occurrence and distribution of natural and anthropogenic compounds in shallow ground water underlying recently developed (post 1963) residential and commercial areas. Monitoring wells from 23 to 153 feet deep were installed at 30 sites. Water-quality data for the monitoring wells consist of analyses of field parameters, major ions, trace elements, nutrients, dissolved organic carbon, pesticides, and volatile organic compounds. Dissolved-solids concentration ranged from 134 to 2,910 milligrams per liter (mg/L) in water from the 30 monitoring wells. Dissolved arsenic concentration in water from 12 wells exceeded the drinking-water maximum contaminant level of 10 micrograms per liter. Water from monitoring wells in the northwestern part of the valley generally contained higher arsenic concentrations than did water from other areas. Nitrate concentration in water sampled from 26 of the 30 monitoring wells (86.7 percent) was higher than a background level of 2 mg/L, indicating a possible human influence. Nitrate concentrations ranged from less than 0.05 to 13.3 mg/L. Fifteen of the 104 pesticides and pesticide degradation products analyzed for were detected in 1 or more water samples from the monitoring wells. No pesticides were detected at concentrations that exceeded U.S. Environmental Protection Agency drinking-water standards or guidelines for 2002. The high detection frequency of atrazine, a restricted-use pesticide, in residential areas on the west side of Salt Lake Valley may be the result of application in agricultural or industrial areas that have been converted to residential uses or application in areas upgradient from the residential areas that was then transported by ground water. Fifteen of the 86 volatile organic compounds analyzed for were detected in 1 or more water samples from the monitoring wells. The most frequently detected volatile organic compounds were chloroform (90 percent), bromodichloromethane (56.7 percent), tetrachloroethylene (53.3 percent), and 1,1,1-trichloroethane (50 percent). The widespread occurrence of chloroform and bromodichloromethane in shallow ground water is likely a result of the recharge of chlorinated public-supply water used to irrigate lawns and gardens in residential areas of Salt Lake Valley. Tetrachloroethylene (PCE), primarily used as a dry cleaning agent and solvent, was detected in water from 16 wells.

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Hydrogeology of shallow basin-fill deposits in areas of Salt Lake Valley, Salt Lake County, Utah

A study of recently developed residential/commercial areas of Salt Lake Valley, Utah, was done from 1999 to 2001 in areas in which shallow ground water has the potential to move to a deeper aquifer that is used for public supply. Thirty monitoring wells were drilled and sampled in 1999 as part of the study. The ground water was either under unconfined or confined conditions, depending on depth to water and the presence or absence of fine-grained deposits. The wells were completed in the shallowest water-bearing zone capable of supplying water. Monitoring-well depths range from 23 to 154 feet. Lithologic, geophysical, hydraulic-conductivity, transmissivity, water-level, and water-temperature data were obtained for or collected from the wells. Silt and clay layers noted on lithologic logs correlate with increases in electrical conductivity and natural gamma radiation shown on many of the electromagnetic-induction and natural gamma logs. Relatively large increases in electrical conductivity, determined from the electromagnetic-induction logs, with no major changes in natural gamma radiation are likely caused by increased dissolved-solids content in the ground water. Some intervals with high electrical conductivity correspond to areas in which water was present during drilling. Unconfined conditions were present at 7 of 20 monitoring wells on the west side and at 2 of 10 wells on the east side of Salt Lake Valley. Fine-grained deposits confine the ground water. Anthropogenic compounds were detected in water sampled from most of the wells, indicating a connection with the land surface. Data were collected from 20 of the monitoring wells to estimate the hydraulic conductivity and transmissivity of the shallow ground-water system. Hydraulic-conductivity values of the shallow aquifer ranged from 30 to 540 feet per day. Transmissivity values of the shallow aquifer ranged from 3 to 1,070 feet squared per day. There is a close linear relation between transmissivity determined from slug-test analysis and transmissivity estimated from specific capacity. Water-level fluctuations were measured in the 30 monitoring wells from 1999 to July 2001. Generally, water-level changes measured in wells on the west side of the valley followed a seasonal trend and wells on the east side showed less fluctuation or a gradual decline during the 2-year period. This may indicate that a larger percentage of recharge to the shallow ground-water system on the west side is from somewhat consistent seasonal sources, such as canals and unconsumed irrigation water, as compared to sources on the east side. Water levels measured in monitoring wells completed in the shallow ground-water system near large-capacity public-supply wells varied in response to ground-water withdrawals from the deeper confined aquifer. Water temperature was monitored in 23 wells. Generally, little or no change in water temperature was measured in monitoring wells with a depth to water greater than about 40 feet. The shallower the water level in the well, the greater the water-temperature change measured during the study. Comparison of water levels measured in the monitoring wells and deeper wells in the same area indicate a downward gradient on the east side of the valley. Water levels in the shallow and deeper aquifers in the secondary recharge area on the west side of the valley were similar to those on the east side. Water levels measured in the monitoring wells and nearby wells completed in the deeper aquifer indicate that the vertical gradient can change with time and stresses on the system.

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Selected hydrologic data for Little Cottonwood Creek, Salt Lake County, Utah, September 1998

Metals enter Little Cottonwood Creek in Salt Lake County, Utah, in drainage water that discharges from inactive mines in the watershed (fig. 1). As part of a study to evaluate the effects of this mine drainage on water quality, a sodium chloride tracer was injected into Little Cottonwood Creek during September 17-18, 1998. The purpose of the injection was to quantify stream discharge; to identify inflows, both those observable and those dispersed in the subsurface; and ultimately, to determine which areas within the watershed contribute the most metals to Little Cottonwood Creek. The purpose of this report is to make these data available to agencies responsible for managing the area’ s water resources and to supplement interpretive reports for this study.

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Water quality and macroinvertebrate communities of Emigration and Red Butte Creeks, Salt Lake County, Utah

Residential development in the canyons and foothills surrounding Salt Lake City, Utah, is growing at a rapid pace. Urban development typically degrades the water quality when formerly natural lands are developed. In Emigration Canyon, however, residential development is replacing land formerly used for grazing and recreation. It is not clear how this land use change has affected the water quality and biotic communities in this watershed. The water quality and macroinvertebrate communities of Emigration Creek and neighboring Red Butte Creek were examined by the U.S. Geological Survey (USGS) as part of the National Water-Quality Assessment Program (NAWQA) during summer 1999.

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Quality of shallow ground water in areas of recent residential and commercial development in Salt Lake Valley, Utah, 1999

R esidential and commercial development of about 80 square miles that primarily replaced undeveloped and agricultural areas occurred in Salt Lake Valley, Utah, from 1963 to 1994. The effects of human activities on the quality of shallow ground water in the recently developed areas were studied by the U.S. Geological Survey (USGS) as part of the National Water-Quality Assessment (NAWQA) program. The land-use study consisted of 30 monitoring wells installed and sampled in 1999 in residential/commercial areas where shallow ground water has the potential to move to a deeper public- supply aquifer. The water samples were analyzed for major ions, nutrients, pesticides, volatile organic compounds (VOCs), trace elements, and radon. The occurrence of nitrate, pesticides, and VOCs in water sampled from these wells can serve as an indicator of water affected by human activities at land surface. This report describes the nitrate, pesticide, and VOC data collected during the study.

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Numerical simulation of solute transport in southwestern Salt Lake Valley, Utah

Contaminated ground water characterized by high concentrations of dissolved solids and dissolved sulfate, and in areas, by low pH and elevated concentrations of metals, is present near public-supply wells in the southwestern Salt Lake Valley. To provide State officials and water users with information concerning the potential movement of contaminated ground water to points of withdrawal in the area, an analysis of solute transport using computer models was done by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, and local municipalities and water users. A three-dimensional solute-transport model was developed and couples with an existing ground-water flow model of Salt Lake Valley to simulate the movement of dissolved sulfate in ground water in southwestern Salt Lake Valley. Development and calibration of the transport model focused mainly on sulfate movement down-gradient from the Bingham Creek Reservoirs and the South Jordan evaporation ponds east of the mouth of Bingham Canyon. Estimates of transport parameters were adjusted during a calibration simulation representing conditions during 1965-93. After calibration, the transport model was used to simulate future sulfate movement for 1994-2043. Because of uncertainty in estimated transport-parameter values, three projection transport simulations incorporating a range of probable parameter values were done to evaluate future sulfate movement and changes in sulfate concentrations at selected public-supply wells. These projection simulations produced a possible range of computed transport rates and patterns. In general, the projection simulations indicated movement of the sulfate plume east of the Bingham Creek reservoir toward public-supply wells northeast of the reservoirs and then eastward toward the Jordan River. Ground water with high concentrations of sulfate east of the South Jordan evaporation ponds is simulated as moving west to east under the Jordan River towards public-supply wells during the final 25 years of the simulation period. An increase in sulfate concentration from 200 mg/l in 2006 to 4,100 mg/l in 2022 was the largest simulated increase at public-supply wells northeast of the reservoirs. An increase in sulfate concentration from 150 mg/l in 2024 to 340 mg/l in 2043 was the largest simulated increase at public-supply wells in the south-central Salt Lake Valley just east of the Jordan River.

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Numerical simulation of ground-water flow in basin-fill material in Salt Lake Valley, Utah

A three-dimensional, finite-difference, numerical model was developed to simulate ground-water flow in the basin-fill material in Salt Lake Valley, Utah. The model was calibrated to steady-state and transient-state conditions. The steady-state simulation was developed and calibrated using hydrologic data defining average conditions for 1968. The transient-state simulation was developed and calibrated using hydrologic data from 1969-91. Areally the model grid is 94 rows by 62 columns, with each cell 0.35 mile on a side. Vertically, the aquifer system is divided into seven layers. The model simulates recharge to the basin-fill ground-water flow system from (1) consolidated rock, (2) streams and canals, (3) precipitation on the valley floor, (4) irrigated land, (5) reservoirs and evaporation ponds in the southwestern part of the valley, and (6) underflow at Jordan Narrows. Estimated discharge to wells, canals, and springs is incorporated in the model. During simulation, the model computes (1) ground-water flow to and seepage from the Jordan River and the lower reaches of its principal tributaries, (2) recharge from consolidated rock at the northern end of the Oquirrh Mountains, (3) discharge to drains, and (4) discharge by evapotranspiration. During steady-state calibration, calibration variables were adjusted within probable ranges to minimize differences between model-computed and measured water levels, model-computed and estimated ground-water discharge to the Jordan River, and simulated and measured vertical hydraulic gradients. The transient-state simulation was calibrated to measured water-level changes and estimated annual gains in the Jordan River.

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Particle-tracking analysis of flow paths and travel times within the capture areas of well fields in Salt Lake Valley, Utah

A particle-tracking analysis was done to estimate capture zones for selected public-supply wells in Salt Lake Valley. Twenty-five- and 50-year capture zones were estimated using a regional, finite-difference, ground-water flow model in conjunction with a particle-tracking program. Three sets of wells currently discharging ground water of adequate quality for public use, but located near areas of ground water with high dissolved-solids concentrations, were selected for the analysis. These included five wells in central Salt Lake Valley near the former Vitro chemical-processing site, four wells in southwestern Salt Lake Valley northeast of Copperton, and five wells in southeastern Salt Lake Valley between Midvale and Sandy. Capture zones were estimated for the wells for current average pumping and projected increased pumping. The quality of ground water within the estimated capture zones was evaluated by comparing the extent of the zones with the distribution of dissolved solids in the ground water surrounding the selected wells. Results of the analysis of wells in central Salt Lake Valley indicate that most of the volume of ground water within the well’s capture zones is characterized by dissolved-solids concentration of less than 500 milligrams per liter. Estimated capture zones of wells in southwestern and southeastern Salt Lake Valley contain ground water with higher dissolved-solids concentrations than ground water currently being discharged by those wells. Estimated 50-year capture zones of selected wells in southwestern Salt Lake Valley contain ground water with dissolved-solids concentrations exceeding 5,000 milligrams per liter. Estimated 50-year capture zones for wells in southeastern Slat Lake Valley, based on simulation of projected increased pumping, indicate flow toward the wells from an area of ground water west of the Jordan River characterized by dissolved-solids concentrations exceeding 1,000 milligrams per liter.

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Ground-water conditions in Salt Lake Valley, Utah, 1969-83, and predicted effects of increased withdrawals from wells

This report was prepared in cooperation with several organizations in the Salt Lake Valley and with the Central Utah Water Conservancy District to present results of a study to determine changes in the ground-water conditions in Salt Lake Valley, Utah, from 1969 to 1983, and to predict the aquifer response to projected withdrawals. The average annual recharge and discharge from the ground-water reservoir in Salt Lake Valley, Utah, during 1969-82 were estimated to be about 352,000 and 353,000 acre-feet per year. Withdrawals from wells increased from 107,000 acre-feet per year during 1964-68 to 117,000 acre-feet per year during 1969-82. The greatest increase in use was for public supply and institutions which increased from 35,000 acre-feet per year during 1964-68 to 46,700 acre-feet per year during 1969-82.

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Chemical quality of ground water in Salt Lake Valley, Utah, 1969-85

During 1979-84, 35 wells completed in the principal aquifer in the Salt Lake Valley, Utah, that had been sampled during 1962-67 were resampled to determine if water-quality changes had occurred. The dissolved-solids concentration of the water from 13 of the wells has increased by more than 10 percent since 1962-67.

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Seepage study of six canals in Salt Lake County, Utah, 1982-1983

A study of selected reaches of the Utah and Salt Lake, Utah Lake Distributing, Provo Reservoir, Draper Irrigation, East Jordan, and Jordan and Salt Lake City Canals in Salt Lake County, Utah, was made to determine gains or losses of flow in those reaches. Three to five sets of seepage measurements were made on each canal during 1982 or 1983. Adjustments for fluctuations in flow were made from information obtained from water-stage recorders operated at selected locations during the time of each seepage run. The study showed an overall net loss of about 9.5 cubic feet per second in the Utah and Salt Lake Canal, 11.0 cubic feet per second in the Utah Lake Distributing canal, 20.5 cubic feet per second in the Provo Reservoir canal, 1.5 cubic feet per second in the Draper Irrigation Canal, and 4.0 cubic feet per second in the East Jordan canal. It also showed a net gain of about 6.0 cubic feet per second in the Jordan and Salt Lake City Canal. The gains and losses are attributed primarily to the relation of the canals to the depth of the water table near the canals.

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Quality and quantity of runoff and atmospheric deposition in urban areas of Salt Lake County, Utah, 1980-81

Water of good quality from mountain streams is degraded as it moves through urban areas to the Jordan River in Salt Lake County, Utah. The impact of urban runoff and atmospheric deposition on the quality of water in those streams and in storm conduits and canals functioning as storm drains was evaluated using data collected during 1980-81. Atmospheric-wetfall loads for an average storm were as much as 10 pounds per acre for total solids, but the dissolved trace metals were generally present in insignificant quantities. Wetfall-deposition loads generally were greater than storm-runoff loads, indicating that a large quantity of the wetfall load remained as soil deposits. Acid rain fell in more than one-half of the storms sampled, most commonly in September and October. Dustfall concentrations reflected the composition of local soils, particularly with regard to iron, manganese, and chromium; but concentrations of cadmium, copper, lead, zinc, and chloride were considerably enriched. Monthly loads of dryfall solids reached a maximum of 62 pounds per acre in the Little Cottonwood Creek urban basin, but were of the same magnitude as total storm loads for a heavy rainfall. Urban runoff represented about 38 percent of the discharge in three canals. The water in the canals was poorer in quality than the water in the mountain streams. The impact of the canal discharges to the streams is slight, however, owing to their ' relatively small amounts. ' Concentrations of sediment, suspended solids, suspended trace metals, phosphorus, and oxygen-demanding substances were much greater during storm runoff than under base-flow conditions. This report contains data for basin and storm characteristics and water-quality information for atmospheric deposition and urban runoff. (USGS)

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Surface-water and climatological data, Salt Lake County, Utah, water year 1980

This report presents streamflow, water-quality, precipitation, and storm-runoff data collected in Salt Lake County, Utah, during the 1980 water year and certain water-quality data for the 1979 water year which were included for comparative purposes. Surface-water data consist of daily mean values of flow at 33 sites on natural streams, canals, and conduits. Water-quality data consist of chemical, biologic, and sediment analyses at 30 sites. Precipitation data consist of daily and monthly total at nine sites. Storm-runoff data consist of 5 and 15-minute interval discharge data for storms of July 1-2, August 19, and August 25, 1980, for most surface-water sites.

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Map showing the thickness of loosely packed sediments and the depth to bedrock in the Sugar House quadrangle, Salt Lake County, Utah

This map provides information on the location and distribution of three general types of geologic materials in part of Salt Lake County, including the southeastern part of Salt Lake City, Utah. These materials have different physical properties that are pertinent to comprehensive planning and zoning, land-use studies, and engineering usage. The map should be of use in preliminary studies to determine the depth to different general types of foundation material and to determine the potential for settlement of the ground surface during major earthquakes, which could result in damage to waterlines, gaslines, large buildings, and other major engineering structures. The lines on the map are generalized. Lines showing the thickness of loosely packed sediments are based on drillers’ logs of 27 water wells in and near the 35-square-mile part of the quadrangle west of the mountains – less than one data point for each square mile. Lines showing the depth to bedrock are based on indirect geophysical data, and the data points are more widely scattered. The map may be useful as a general guide in planning, but investigations by qualified specialists should be made for detailed evaluations of specific areas. references to other reports of possible interest to the reader are included at the end of this text.

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