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At least 55 records · Page 3Linked to original sources
USGS2008

Water- and air-quality monitoring of Sweetwater Reservoir watershed, San Diego County, California — Phase one results continued, 2001-2003

In 1998, the U.S. Geological Survey, in cooperation with the Sweetwater Authority, began a study to monitor water, air, and sediment at the Sweetwater and Loveland Reservoirs in San Diego County, California. The study includes regular sampling of water and air at Sweetwater Reservoir for chemical constituents, including volatile organic compounds (VOC), polynuclear aromatic hydrocarbons (PAH), pesticides, and major and trace elements. The purpose of this study is to monitor changes in contaminant composition and concentration during the construction and operation of State Route 125. To accomplish this, the study was divided into two phases. Phase One sampling (water years 1998–2004) determined baseline conditions for the detection frequency and the concentrations of target compounds in air and water. Phase Two sampling (starting water year 2005) continues at selected monitoring sites during and after construction of State Route 125 to assess the chemical impact this roadway alignment may have on water quality in the reservoir. Water samples were collected for VOCs and pesticides at Loveland Reservoir during Phase One and will be collected during Phase Two for comparison purposes. Air samples collected to monitor changes in VOCs, PAHs, and pesticides were analyzed by adapting methods used to analyze water samples. Bed-sediment samples have been and will be collected three times during the study; at the beginning of Phase One, at the start of Phase Two, and near the end of the study. In addition to the ongoing data collection, several special studies were initiated to assess the occurrence of specific chemicals of concern, such as trace metals, anthropogenic indicator compounds, and pharmaceuticals. This report describes the study design, and the sampling and analytical methods, and presents data from water and air samples collected during the fourth and fifth years of Phase One of the study (October 2001 to September 2003). Data collected during the first three years has been previously published. Three types of quality-control samples were used in this study: blanks, spikes, and replicates. Blanks and spikes are used to estimate result bias, and replicates are used to estimate result variability. Additionally, surrogate compounds were added at the laboratory to samples of VOCs, PAHs, pesticides, anthropogenic indicator compounds, and pharmaceuticals to monitor sample-specific performance of the analytical method.

California↗
USGS1956

Sedimentation and chemical quality of surface waters in the Wind River basin, Wyoming

This report gives results of an investigation by the U. S. Geological Survey of chemical quality of surface waters and sedimentation in the Wind River Basin, Wyo. The sedimentation study was begun in 1946 to determine the quantity of sediment that is transported by the streams in the basin; the probable sources of the sediment; the effect of large irrigation projects on sediment yield, particularly along Fivemile Creek; and the probable specific weight of the sediment when initially deposited in a reservoir. The study of the chemical quality of the water was begun in 1945 to obtain information on the sources, nature, and amounts of dissolved material that is transported by streams and on the suitability of the waters for different uses. Phases of geology and hydrology pertinent to the sedimentation and chemical quality were studied. Results of the investigation through September 30, 1952, and some special studies that were made during the 1953 and 1954 water years are reported. The rocks in the Wind River Basin are granite, schist, and gneiss of Precambrian age and a thick series of sedimentary strata that range in age from Cambrian to Recent. Rocks of Precambrian and Paleozoic age are confined to the mountains, rocks of Mesozoic age crop out along the flank of the Wind River and Owl Creek Mountains and in denuded anticlines in the floor of the basin, and rocks of Tertiary age cover the greater part of the floor of the basin. Deposits of debris from glaciers are in the mountains, and remnants of gravel-capped terraces of Pleistocene age are on the floor of the basin. The lateral extent and depth of alluvial deposits of Recent age along all the streams are highly variable. The climate of the floor of the basin is arid. The foothills probably receive a greater amount of intense rainfall than the areas at lower altitudes. Most precipitation in the Wind River Mountains falls as snow. The foothill sections, in general, are transitional zones between the cold, humid climate of the high mountains and the warmer, drier climate of the basin floor. Average annual runoff in the basin is about 3.6 inches on the basis of adjusted streamflow records for the Bighorn River near Thermopolis. Runoff from the mountains is high and is mostly from melting of snow and from spring and early summer rains. It does not vary greatly from year to year because annual water losses are small in comparison to annual precipitation. In the areas on the floor of the basin, where runoff is low, the runoff is mostly the result of storms in late spring and early summer. The annual water losses nearly equal the annual precipitation; therefore, runoff is extremely variable, in terms of percentage changes, from year to year and from point to point during any 1 year.

Water Supply Paper↗
USGS1992

Progress report on the Worldwide Earthquake Risk Management (WWERM) Program

Considerable progress has been made in the Worldwide Earthquake Risk Management (WWERM) Program since its initiation in late 1989 as a cooperative program of the Agency for International Development (AID), Office of U.S. Foreign Disaster Assistance (OFDA), and the U.S. Geological Survey. Probabilistic peak acceleration and peak Modified Mercalli intensity (MMI) maps have been prepared for Chile and for Sulawesi province in Indonesia. Earthquake risk (loss) studies for dwellings in Gorontalo, North Sulawesi, have been completed and risk studies for dwellings in selected areas of central Chile are underway. A special study of the effect of site response on earthquake ground motion estimation in central Chile has also been completed and indicates that site response may modify the ground shaking by as much as plus or minus two units of MMI. A program for the development of national probabilistic ground motion maps for the Philippines is now underway and pilot studies of earthquake ground motion and risk are being planned for Morocco.

Conference Paper↗
USGS2003

Cross-channel variability in benthic habitat

Benthic invertebrates play an important role in estuarine food webs and biogeochemical cycling of carbon, nutrients, and contaminants. The generally sedentary benthic invertebrates continuously integrate local water, sediment, and food conditions. This makes them good indicators of the type and quality of aquatic habitat at the location where they are found. The Interagency Ecological Program’s Environmental Monitoring Program (EMP) has monitored benthic invertebrates since the mid-1970s. A recent review of the EMP found that the spatial study design of the benthos monitoring element was in need of a thorough reexamination through intense special studies and extensive historic data analyses. This article reports the results of preliminary analyses of historical EMP data focusing on cross-channel variability. Specific questions are: (1) do benthic habitats and community assemblages vary between positions across a river channel? (2) Are benthic samples taken at a single channel position sufficiently representative of benthos assemblages across the channel to characterize long term changes in the benthos community of a particular section of a river?

California↗
USGS1983

Aquifer systems in the Great Basin region of Nevada, Utah, and adjacent states: A study plan

The Great Basin Regional Aquifer Study includes about 140,000 square miles in parts of Nevada, Utah, California, Idaho, Oregon, and Arizona. Within that area, 240 hydrographic areas occupy structural depressions formed primarily by basin-and-range faulting. The principal aquifers are in basin- fill deposits; however, permeable carbonate rocks underlie valleys in much of eastern Nevada and western Utah and are significant regional aquifers. Anticipated future water needs require a better understanding of the resource so that wise management will be possible. In October 1980, the U.S Geological Survey started a 4-year study to (1) describe the ground-water systems as they existed under natural conditions and as they exist today, (2) analyze the changes that have led to the systems' present condition, (3) tie the results of this and previous studies together in a regional analysis, and (4) provide means by which effects of future ground-water development can be estimated. A plan of work is presented that describes the general approach to be taken in this study. It defines (1) the major task necessary to meet objectives and (2) constraints on the scope of work. The approach has been strongly influenced by the diverse nature of ground-water flow systems and the large number of basins. A detailed appraisal of 240 individual areas would require more resources than are available. Consequently, the general approach is to study selected "typical" areas and key hydrologic processes. Effort during the first 3 years will be directed toward describing the regional hydrology, conducting detailed studies of "type" areas, and studying selected hydrologic processes. Effort during the final year will be directed toward developing a regional analyses of results. Special studies that will address hydrologic processes, key components of the ground-water system, and improved use of technology include evaluations of regional geochemistry, regional hydrogeology, recharge, ground-water discharge, and the use of remote sensing. Areas selected for study using ground-water flow models include the regional carbonate-rock province in eastern Nevada and western Utah, six valleys Las Vegas, Carson, Paradise, Dixie, Smith Creek, and Stagecoach in Nevada, plus Jordan Valley, the Milford area, and Tule Valley in Utah.

Nevada, Utah↗
USGS2001

Water resources data, Mississippi, water year 2000

Water resources data for the 2000 water year for Mississippi consist of records of surface water and ground water in the State. Specifically, it contains: (1) Discharge records for 96 streamflow-gaging stations, stage records for 19 of these gaging stations, discharge records for 73 partial-record or miscellaneous streamflow stations, including 7 flood hydrograph partial-record stations, 70 crest-stage partial-record stations, and 4 special study and miscellaneous sites; (2) stage only at 1 gaging station; (3) water-quality records for 15 streamflow-gaging stations, 3 partial-record or miscellaneous sites, 59 short-term study sites, and 24 wells; and (4) water-level records for 18 observation wells. Records obtained from water-resources investigations are also included in special sections of the report. These data represent that part of the National Water Data System operated by the U.S. Geological Survey, and cooperating local, State, and Federal agencies in Mississippi.

Mississippi↗
USGS2002

Water resources data, Mississippi, water year 2001

Water resources data for the 2001 water year for Mississippi consist of records of surface water and ground water in the State. Specifically, it contains: (1) Discharge records for 95 streamflow-gaging stations, stage records for 20 of these gaging stations, discharge records for 83 partial-record or miscellaneous streamflow stations, including 8 flood hydrograph partial-record stations, 70 crest-stage partial-record stations, and 5 special study and miscellaneous sites; (2) stage only at 1 gaging station; (3) water-quality records for 8 streamflow-gaging stations, 0 partial-record or miscellaneous sites, 9 short-term study sites, and 27 wells; and (4) water-level records for 18 observation wells. Records obtained from water-resources investigations are also included in special sections of the report. These data represent that part of the National Water Data System operated by the U.S. Geological Survey, and cooperating local, State, and Federal agencies in Mississippi.

Mississippi↗
USGS2003

Water Resources Data, Mississippi, Water Year 2002

Water resources data for the 2002 water year for Mississippi consist of records of surface water and ground water in the State. Specifically, it contains: (1) Discharge records for 91 streamflow-gaging stations, stage records for 22 of these gaging stations, discharge records for 91 partial-record stations or miscellaneous streamflow sites, including 13 flood hydrograph partial-record stations, 78 crest-stage partial-record stations, and 0 special study and miscellaneous sites; (2) stage only at 9 gaging stations; (3) water-quality records for 13 streamflow-gaging stations, 7 stage-only stations, and 3 water-quality monitor stations, 0 partial-record stations or miscellaneous sites, 97 short-term study sites, and 39 wells; and (4) water-level records for 18 observation wells. Records obtained from water-resources investigations are also included in special sections of the report. These data represent that part of the National Water Data System operated by the U.S. Geological Survey, and cooperating local, State, and Federal agencies in Mississippi.

Water Data Report↗
USGS2004

Water Resources Data Mississippi Water Year 2003

Water resources data for the 2003 water year for Mississippi consist of records of surface water and ground water in the State. Specifically, it contains: (1) Discharge records for 94 streamflow-gaging stations, stage records for 20 of these gaging stations, discharge records for 98 partial-record stations or miscellaneous streamflow sites, including 10 flood hydrograph partial-record stations, 78 crest-stage partial-record stations, and 10 special study and miscellaneous sites; (2) stage only at 7 gaging stations; (3) water-quality records for 10 streamflow-gaging stations, 5 stage-only stations, 3 water-quality monitor stations, 0 partial-record stations or miscellaneous sites, 11 short-term study sites, and 24 wells; and (4) water-level records for 19 observation wells. Records obtained from water-resources investigations are also included in special sections of the report. These data represent that part of the National Water Data System operated by the U.S. Geological Survey, in cooperation with State, county, municipal, and other Federal agencies in Mississippi.

Water Data Report↗
USGS2005

Water resources data Mississippi water year 2004

Water resources data for this water year for Mississippi consists of records of surface water and ground water in the State. Specifically, it contains: (1) Discharge records for 90 streamflow-gaging stations, stage records for 18 of these gaging stations, discharge records for 97 partial-record stations or miscellaneous streamflow sites, including 6 flood hydrograph partial-record stations, 91 crest-stage partial-record stations and 0 special study and miscellaneous sites; (2) stage only at 1 gaging station; (3) water-quality records for 12 streamflow-gaging stations, 0 stage-only stations, 13 water-quality monitor stations, 0 partial-record stations or miscellaneous sites, 0 short-term study sites, and 26 wells; and (4) water-level records for 19 observation wells. Records obtained from water-resources investigations are also included in special sections of the report. Records included for stream stages are only a small fraction of those obtained during the water year.

Water Data Report↗
USGS1996

Water resources data, Mississippi, water year 1995

Water resources data for the 1995 water year for Mississippi consist of records of surface water and ground water in the State. Specifically, it contains: (1) Discharge records for 86 streamflow-gaging stations, stage records for 20 of these gaging stations, discharge records for 80 partial-record or miscellaneous streamflow stations, including 8 flood hydrograph partial-record stations, 54 crest-stage partial-record stations, and 18 special study and miscellaneous sites; (2) stage only at 6 gaging stations; (3) water-quality records for 22 streamflow-gaging stations, 1 ungaged stream site, 9 partial-record or miscellaneous sites, 50 short-term study sites, and 72 wells; and (4) water-level records for 47 observation wells. Records obtained from water-resources investigations are also included in special sections of the report. These data represent that part of the National Water Data System operated by the U.S. Geological Survey, and cooperating local, State, and Federal agencies in Mississippi.

Mississippi↗
USGS1997

Water resources data, Mississippi, water year 1996

Water resources data for the 1996 water year for Mississippi consist of records of surface water and ground water in the State. Specifically, it contains: (1) Discharge records for 88 streamflow-gaging stations, stage records for 19 of these gaging stations, discharge records for 66 partial-record or miscellaneous streamflow stations, including 7 flood hydrograph partial-record stations, 53 crest-stage partial-record stations, and 6 special study and miscellaneous sites; (2) stage only at 4 gaging stations; (3) water-quality records for 21 streamflow-gaging stations, 1 ungaged stream site, 2 partial-record or miscellaneous sites, 64 short-term study sites, and 26 wells; and (4) water-level records for 46 observation wells. Records obtained from water-resources investigations are also included in special sections of the report. These data represent that part of the National Water Data System operated by the U.S. Geological Survey, and cooperating local, State, and Federal agencies in Mississippi.

Mississippi↗
USGS1999

Water resources data, Mississippi, water year 1998

Water resources data for the 1998 water year for Mississippi consist of records of surface water and ground water in the State. Specifically, it contains: (1) Discharge records for 97 streamflow-gaging stations, stage records for 19 of these gaging stations, discharge records for 73 partial-record or miscellaneous streamflow stations, including 7 flood hydrograph partial-record stations, 51 crest-stage partial-record stations, and 15 special study and miscellaneous sites; (2) stage only at 1 gaging station; (3) water-quality records for 13 streamflow-gaging stations, 3 partial-record or miscellaneous sites, 8 short-term study sites, and 43 wells; and (4) water-level records for 34 observation wells. Records obtained from water-resources investigations are also included in special sections of the report. These data represent that part of the National Water Data System operated by the U.S. Geological Survey, and cooperating local, State, and Federal agencies in Mississippi.

Mississippi↗
USGS2000

Water resources data, Mississippi, water year 1999

Water resources data for the 1999 water year for Mississippi consist of records of surface water and ground water in the State. Specifically, it contains: (1) Discharge records for 97 streamflow-gaging stations, stage records for 19 of these gaging stations, discharge records for 79 partial-record or miscellaneous streamflow stations, including 7 flood hydrograph partial-record stations, 70 crest-stage partial-record stations, and 2 special study and miscellaneous sites; (2) stage only at 2 gaging stations; (3) water-quality records for 18 streamflow-gaging stations, 4 partial-record or miscellaneous sites, 11 short-term study sites, and 39 wells; and (4) water-level records for 18 observation wells. Records obtained from water-resources investigations are also included in special sections of the report. These data represent that part of the National Water Data System operated by the U.S. Geological Survey, and cooperating local, State, and Federal agencies in Mississippi.

Mississippi↗
USGS1994

Water resources data, Mississippi, water year 1993

Water resources data for the 1993 water year for Mississippi consist of records of surface water, ground water, and precipitation in the State. Specifically, it contains:(1) Discharge records for 83 streamflow-gaging stations, stage records for 19 of these gaging stations, discharge records for 107 partial-record or miscellaneous streamflow stations, including 7 flood hydrograph partial-record stations, 55 crest-stage partial-record stations and 46 special study and miscellaneous sites, (2) stage only at 6 gaging stations,(3) water-quality records for 24 streamflow-gaging stations, 2 ungaged streamsites 6 partial-record or miscellaneous sites, 21 short-term study sites, 384 wells, and 3 precipitation-quality stations, and (4) water-level records for 231 observation wells. Records obtained from water-resources investigations are also included in special sections of the report. These data represent that part of the National Water Data System operated by the U.S. Geological Survey, and cooperating local, State, and Federal agencies in Mississippi.

Mississippi↗
USGS2005

Occurrence and distribution of volatile organic compounds and pesticides in ground water in relation to hydrogeologic characteristics and land use in the Santa Ana basin, southern California

This report presents an evaluation of the occurrence and distribution of VOCs and pesticides in the Santa Ana ground-water basins in relation to two types of explanatory factors: hydrogeologic characteristics and land use. The Santa Ana Basin is subdivided into the San Jacinto, the Inland, and the Coastal ground-water basins. Most wells sampled were deep and used for public supply. Data from regional studies were used to evaluate the occurrence and distribution of pesticides and volatile organic compounds (VOCs) in relation to hydrogeologic characteristics and land uses that could potentially explain variations between basins. Additional data from special studies (flow path and aquifer susceptibility) were used to evaluate potential factors affecting water quality for individual basins. The hydrogeologic characteristics evaluated in this report were hydrogeologic setting, ground-water age, depth to the top of the well screen (top of well perforations), and proximity to engineered recharge facilities. Urban land use, agricultural land use, and population density were characterized within a 500-meter radius of sampled wells and at the basin scale. Aquifers in the San Jacinto Basin are generally unconfined, and major land-use categories are urban (33 percent), agricultural (37 percent), and undeveloped (25 percent). Recharge is primarily from the overlying landscape, but engineered recharge is locally important in the Hemet area. VOCs and pesticides were detected more frequently in younger ground water (less than 50 years old) than in older ground water, and more frequently in shallower wells than deeper wells; the numbers of VOCs and pesticides detected also were significantly higher in the younger ground water and in the shallower wells. In the Hemet area of the San Jacinto Basin, VOCs and pesticides were detected more frequently in wells proximal to engineered recharge facilities than in distal wells. These patterns illustrate the importance of proximity to sources of recharge in relation to the occurrence and distribution of VOCs and pesticides in ground water. Aquifers in the Inland Basin also are generally unconfined, and the major land-use category is urban (58 percent), with lesser amounts of agricultural (13 percent) and undeveloped (28 percent) land. Recharge is from engineered facilities that utilize local runoff and imported water and from vertical infiltration. VOCs and pesticides were detected more frequently in younger ground water than in older ground water, and more frequently in shallower wells than deeper wells. The number of VOCs detected per well also was significantly higher in the younger ground water and in the shallower wells. Several solvent plumes extending between 5 and 10 kilometers illustrate the large distances that contaminants travel in basins with intensive use of ground water. Aquifers in the Coastal Basin, in contrast to the other basins, are generally confined. Land use in the basin is largely urban (80 percent), with lesser amounts of agricultural (7 percent) and undeveloped (12 percent) land. Recharge is primarily from engineered facilities that utilize water diverted from the Santa Ana River and imported water. Consequently, VOCs and pesticides were detected more frequently in wells proximal to engineered recharge facilities than in distal wells. These compounds were also detected more frequently in the unconfined area than in the confined area of the basin. In the confined area, the numbers of VOCs and pesticides detected per well were not significantly different in wells with shallower and deeper screens. This distribution reflects the dominance of lateral flow and insulation from overlying land use in the confined aquifers of the Coastal Basin. In the unconfined area of the Coastal Basin, the numbers of VOCs and pesticides detected per well were significantly higher in shallower wells than in deeper wells. VOC and pesticide detections were not statist

Scientific Investigations Report↗
USGS1979

Selected bibliography on subsidence processes and related engineering problems in carbonate rocks

The Solution Subsidence and Collapse project is a U.S. Geological Survey research activity funded by the Reactor Hazards Research program. The objective of the study is to determine the geologic and hydrologic controls and mechanisms of ground subsidence in soluble rock terranes caused by natural processes and man's activities. The results of the research will be used for the general geologic characterization of proposed and existing nuclear reactor sites in regions underlain by soluble rocks. In addition, the knowledge gained from the study will be applied to defining potential geologic hazards in soluble rock areas where ground subsidence or collapse can occur. The Solution Subsidence and Collapse project is divided into two study units, one looking at subsidence in evaporitic terranes, the other in carbonate terranes. Each of the two geologic environments has its own unique set of conditions that lead to subsidence and, therefore, each warrants its own special study. As part of the subsidence study a selected bibliography covering various topics on ground subsidence in carbonate karst terranes was compiled and is presented here. The entries in the bibliography are placed in five categories: (1) General; (2) Geology, Geomorphology, Hydrology; (3) Caves, Solution Channels; (4) Subsidence, Sinkholes; and (5) Engineering, Land Use, Detection. A separate bibliography on ground subsidence caused by dissolution and removal of salt and other soluble evaporites has been published as a companion reference to this report (Ege, 1979).

Open-File Report↗
USGS2014

A study of salt‐water encroachment in the Galveston Area, Texas

A survey of the ground‐ water resources of the region in which Houston and Galveston are situated was started in December 1930 by the United States Geological Survey in cooperation with the Texas Board of Water Engineers. In connection with this survey a special study is being made of the geochemical relations of the ground‐waters of an area about 25 miles wide and 90 miles long, extending from Galveston northwestward through Houston. This study considers the influence on the ground‐waters of the age and degree of weathering of the outcrop formations, base‐exchange materials, salt ‐domes, and salt ‐ water encroachment . In this paper, however, attention is confined to salt ‐ water encroachment along the line from Galveston to Houston (Fig. 1).

Texas↗