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At least 775 records · Page 43Linked to original sources

USGS1977

Reconnaissance of ground-water resources in a part of the Yampa River basin between Craig and Steamboat Springs, Moffat and Routt counties, Colorado

This report presents the results of an investigation of ground-water resources in that part of the Yampa River basin between the towns of Craig and Steamboat Springs. The location of the study area is shown on the index map. The investigation was begun in 1975 by the U.S. Geological Survey in cooperation with the Colorado Department of Natural Resources, Division of Water Resources, Office of the State Engineer.

Colorado↗

USGS1978

Water-resources setting, Martin County, Florida

This report describes some basic principles of hydrology as they apply to Martin County, Florida. The major land features are described first, then the hydrologic cycle and surface-water and ground-water resource. Specific problems associated with population growth and the county 's development, such as saltwater intrusion and water use, are cited and sections have been included to deal with these problems. The report is intended to provide a background on the water resource of Martin County to those who do not have the time nor the need to delve deeply into the county 's hydrologic conditions or its water-management problems. It is freely illustrated and uses a minimum of text to explain the illustrations. General data on the water resources of the county are given, but few specific basic data are presented. (Woodard-USGS)

Florida↗

USGS1993

Water resources of Washakie County, Wyoming

Data on the surface- and ground-water resources are complied to summarize the water resources of Washakie County. This study, prepared in cooperation with the Wyoming State Engineer, is one in a series investigating the water resources of Wyoming counties . The three principal types of streams in the county are perennial, intermittent, and ephemeral. Perennial streams have continuous streamflows, and high streamflows are associated with snowmelt runoff; low streamflows usually occur in the winter months when the snowpack is frozen and ground-water discharge is at its smallest rate. Intermittent and ephemeral streams are characterized by periods of no flow, and high streamflows are associated with snowmelt or thunderstorms. The principal aquifers are as follows: alluvium of Quaternary age, Willwood Formation of Tertiary age, Fort Union Formation of Tertiary age, and the formations of primarily Paleozoic age--Goose Egg Formation, Tensleep Sandstone, Madison Limestone, Bighorn Dolomite, and Flathead Sandstone. Reported yields from wells completed in the alluvium ranged from 10 to 40 gallons per minute, and reported yields from wells completed in the Willwood Formation ranged from 1 to 28 gallons per minute. Yields as large as 2,500 gallons per minute are reported from wells completed in the Madison Limestone, Bighorn Dolomite, and Flathead Sandstone. Calcium magnesium sodium sulfate water and sodium sulfate water with concentrations of dissolved solids greater than 1,000 milligrams per liter are common in the alluvium, Willwood Formation and Fort Union Formation. Water samples from six of eight wells completed in the Willwood Formation have trace concentrations of herbicides. Calcium carbonate water with small dissolved-solids concentrations is common in the aquifers in Paleozoic formations.

Wyoming↗

USGS1994

Water resources of Duval County, Florida

The report describes the hydrology and water resources of Duval County, the development of its water supplies, and water use within the county. Also included are descriptions of various natural features of the county (such as topography and geology), an explanation of the hydrologic cycle, and an interpretation of the relationship between them. Ground-water and surface-water resources and principal water-quality features within the county are also discussed. The report is intended to provide the general public with an overview of the water resources Of Duval County, and to increase public awareness of water issues. Information is presented in nontechnical language to enable the general reader to understand facts about water as a part of nature, and the problems associated with its development and use.

Florida↗

USGS1994

Potential effects of the Hawaii Geothermal Project on ground-water resources on the island of Hawaii

In 1990, the State of Hawaii proposed the Hawaii Geothermal Project for the development of as much as 500 MW of electric power from the geothermal system in the East Rift Zone of Kilauea Volcano. This report uses data from 31 wells and 8 springs to describe the properties of the ground-water system in and adjacent to the East Rift Zone. Potential effects of this project on ground-water resources are also discussed. Data show differences in ground-water chemistry and heads within the study area that appear to be related to mixing of waters of different origins and ground-water impoundment by volcanic dikes. East of Pahoa, the ground-water system within the rift is highly transmissive and receives abundant recharge from precipitation; therefore, the pumping of freshwater to support geothermal development in that part of the rift zone would have a minimal effect on ground-water levels. To the southwest of Pahoa, dike impoundment reduces the transmissivity of the ground-water system to such an extent that wells might not be capable of supplying sufficient fresh water to support geothermal operations. Contamination of ground-water resources by accidental release of geothermal fluids into shallow aquifers is possible because of corrosive conditions in the geothermal wells, potential well blowouts, and high ground-water velocities in parts of the region. Hydrologic monitoring of water level, temperature, and chemistry in observation wells should continue throughout development of geothermal resources for the Hawaii Geothermal Project for early detection of leakage and migration of geothermal fluids within the groundwater system.

Water-Resources Investigations Report↗

USGS1996

Atlas of ground-water resources in Puerto Rico and the U.S. Virgin Islands

This atlas presents an overview of the ground-water resources of the main island of Puerto Rico; two of its larger offshore islands, Isla de Culebra and Isla de Vieques; and the three principal islands of the U.S. Virgin Islands, St. Thomas, St. John, and St. Croix. The atlas presents the most important ground-water information available for these islands, and is written for water managers and the general public. It describes, through the use of maps, graphs, and hydrogeologic sections, the most important aspects of the geohydrology, ground-water flow system, and groundwater withdrawals for the principal aquifers in these islands. Most of the information presented in the atlas is from published reports, although unpublished data from ongoing studies by the U.S. Geological Survey were used to prepare parts of the atlas. This report provides a useful compilation of information concerning major aquifers in Puerto Rico and the U.S. Virgin Islands and provides a first step in gaining a general knowledge of these aquifers. More detailed information is available from the primary sources referenced in the report. The atlas contains an introductory section and 15 sections describing the ground-water resources of 12 regions within the 7 ground-water areas of the main island of Puerto Rico, Isla de Culebra and Isla de Vieques (described in a single section of the atlas), and the U.S. Virgin Islands (St. Thomas and St. John are described in one section of the atlas and St. Croix in another), and a concluding section describing present and potential problems related to the development of ground-water resources. Information presented in each of 15 descriptive sections of the atlas include the (1) location and major geographic features of the area covered by that section, (2) population and estimated (4) hydrogeology of the area, (5) ground-water levels and movements, and (6) a description of soil permeabilities.

Water-Resources Investigations Report↗

USGS1996

Assessment of the fresh- and brackish-water resources underlying Dunedin and adjacent areas of northern Pinellas County, Florida

The city of Dunedin is enhancing their potable ground-water resources through desalination of brackish ground water. An assessment of the fresh- and brackish-water resources in the Upper Floridan aquifer was needed to estimate the changes that may result from brackish-water development. The complex hydrogeologic framework underlying Dunedin and adjacent areas of northern Pinellas County is conceptualized as a multilayered sequence of permeable zones and confining and semiconfining units. The permeable zones contain vertically spaced, discrete, water-producing zones with differing water quality. Water levels, water-level responses, and water quality are highly variable among the different permeable zones. The Upper Floridan aquifer is best characterized as a local flow system in most of northern Pinellas County. Pumping from the Dunedin well field is probably not influencing water levels in the aquifer outside Dunedin, but has resulted in localized depressions in the potentiometric surface surrounding production-well clusters. The complex geologic layering combined with the effects of production-well distribution probably contribute to the spatial and temporal variability in chloride concentrations in the Dunedin well field. Chloride concentrations in ground water underlying the Dunedin well field vary both vertically and laterally. In general, water-quality rapidly changes below depths of 400 feet below sea level. Additionally, randomly distributed water-producing zones with higher chloride concentrations may occur at shallow, discrete intervals above 400 feet. A relation between chloride concentration and distance from St. Joseph Sound is not apparent; however, a possible relation exists between chloride concentration and production-well density. Chloride-concentration data from production wells show a consistently increasing pattern that has accelerated since the late 1980's. Chloride-concentration data from 15 observation wells show increasing trends for 6 wells, decreasing trends for 3 wells, and no trend for 6 wells. The current and future, fresh- and brackish-water resources were evaluated using a numerical ground-water flow and solute-transport model. Simulation results indicate that the hydraulic conductivity of the uppermost permeable zone (upper zone A) of the Upper Floridan aquifer is four times greater than the two underlying permeable zones (lower zone A and zone B). The simulated hydraulic conduc- tivities of the semiconfining units are four orders of magnitude less than the permeable zones. Simulation results show the importance of semiconfining units as a mechanism for retarding the vertical movement of higher salinity ground water. Simulation results indicate that pumping from the brackish-water zone does not negatively influence the chloride-concentration trends in the overlying fresh-water zone; however, chloride changes in the fresh-water zone will continue to occur due to the continuation of current fresh-water withdrawals. Chloride changes in the brackish-water zone will occur from pumping brackish water.

Florida↗

USGS1999

Geology and ground-water resources of the Lawrenceville area, Georgia

The population of the Atlanta Metropolitan area continues to grow at a rapid pace and the demand for water supplies steadily increases. Exploration for ground-water resources, as a supplement to surface-water supplies, is being undertaken by many city and county governments. The application of effective investigative methods to characterization of the complex igneous and metamorphic fractured bedrock aquifers of the Piedmont physiographic province is essential to the success of these ground-water exploration programs. The U.S. Geological Survey, in cooperation with the City of Lawrenceville, Ga., began a study in December 1994 to apply various investigative techniques for field characterization of fractured crystalline-bedrock aquifers near Lawrenceville. Five major lithologic units were mapped in the Lawrenceville, Ga., area as part of an ongoing study of ground-water resources-amphibolite, biotite gneiss, button schist, granite gneiss, and quartzite/aluminous schist. These units generally are thin in outcrop width, have low angles of dip (nearly 0 to 20 degrees, dip reversals occur over short distances), and exhibit some shearing characteristics. The most productive unit for ground-water resources, on the basis of subsurface data collected through 1997, is the amphibolite. Historically, two wells drilled into this unit are recognized as having possibly the highest yields in the Piedmont region of northern Georgia. The City of Lawrenceville refurbished one well at the Rhodes Jordan Wellfield in 1990, and has pumped this well at an average rate of about 230 gallons per minute since 1995. In general, the composition of water collected from the bedrock wells, regolith wells, and City Lake is similar; calcium and bicarbonate are the dominant cation and anion, respectively. Water from the regolith wells and the lake have lower concentrations of major ions than does water from the bedrock wells. Many of the ground-water samples collected from the Rhodes Jordan Wellfield during October-November 1995, and from the wellfield and three additional observation well sites during August 1996, contain volatile organic compounds. Volatile organic compounds were detected in ground-water samples collected from several bedrock and regolith wells located in urban areas. Trace concentrations of tetrachloroethylene, trichloroethylene, 1,1-dichloroethane, trichlorofluoromethane, 1,1,1-trichloroethane, and cis-1,2-dichloroethene were detected. Methyl-tert-butyl ether (MTBE)-a compound used to increase the octane level in gasoline-was detected at concentrations above expected urban background levels in bedrock wells in the Rhodes Jordan Wellfield. Concentrations of MTBE ranged from 0.6 to 12 micrograms per liter in October-November 1995, and from 0.6 to 26 micrograms per liter in August 1996. Continuous ground-water-level data suggest that the fractured crystalline-bedrock aquifer (amphibolite unit) at the Rhodes Jordan Wellfield, generally is dewatered to a depth near a productive fracture during the regular pumping cycle of 18 hours per day, 5 days on and 2 days off per week. However, when the stress on the aquifer is increased by extending the pumping period up to as much as 18 days, or by pumping longer that 18 hours per day, the aquifer exhibits an unusual condition of recovery. Areal effects of pumping have been observed at distances of as much as one mile, extending across surface-water drainage divides.

Georgia↗

USGS1999

Water-resources-related information for the Oneida Reservation and vicinity, Wisconsin

Water-resources information has been compiled from 82 studies in which data were collected from the Oneida Reservation and vicinity. Forty-seven studies addressed surface-water issues, 33 studies addressed ground-water issues, and 23 studies addressed aquatic-biology issues. Some multidisciplinary studies are included in more than one category. Most of the surface-water studies summarized in this report included both water-quality and flow information. Several surface-water studies provided detailed short-term descriptions of surface- water quality and flow for parts of the Reservation and vicinity. Surface-water and stream-sediment quality data from several data bases have been compiled for this report. Most of the compiled data come from two sites on Duck Creek. Data from Duck Creek were analyzed for trends in concentrations of suspended sediment, dissolved nitrite plus nitrate, and dissolved atrazine. No trends were detected for any of these constituents. Trends in concentration of most constituents in surface-water samples were not calculated because of the short period of data collection at nearly all of the sites. Most of the ground-water reports that were identified included both quality and quantity and flow information. None of the ground-water studies provided a detailed description of ground-water quality for the Reservation as a whole. Several reports provide varied and detailed information for ground-water models that are useful for understanding hydrogeology and ground-water flow for the Reservation and vicinity. Ground-water quality data from 180 wells, compiled from several data bases, provided an incomplete summary of the condition of the drinking- water resources of the Reservation. Only 12 constituents, from a small number of wells, exceeded a USEPA drinking-water limit. Most of the exceedences were for trace metals and organics. No exceedences for pesticides or nitrate were reported; however, pesticide data were collected from only a small number of wells. Most of the aquatic biology studies described in this report include fish data, habitat data, or calculations of biotic index values, most of which comes from Duck Creek. Historical aquatic biology data for the Reservation and vicinity are limited. Most of the 23 studies described here were done since 1992. Most of the biota-quality data compiled for this report come from several sites on Duck Creek and represent a small number of samples. Results of the community survey regarding the water resources of the Oneida Reservation indicate that water usage by Tribal members today has declined when compared to the past. The most common reason given for the decline in usage was pollution. Most of those surveyed perceived Duck Creek as being "polluted," but about 50 percent thought that water quality in the Reservation was improving.

Wisconsin↗

USGS2015

Decision support system for optimally managing water resources to meet multiple objectives in the Savannah River Basin

Managers of large river basins face conflicting demands for water resources such as wildlife habitat, water supply, wastewater assimilative capacity, flood control, hydroelectricity, and recreation. The Savannah River Basin, for example, has experienced three major droughts since 2000 that resulted in record low water levels in its reservoirs, impacting dependent economies for years. The Savannah River estuary contains two municipal water intakes and the ecologically sensitive freshwater tidal marshes of the Savannah National Wildlife Refuge. The Port of Savannah is the fourth busiest in the United States, and modifications to the harbor to expand ship traffic since the 1970s have caused saltwater to migrate upstream, reducing the freshwater marsh’s acreage more than 50 percent. A planned deepening of the harbor includes flow-alteration features to minimize further migration of salinity, whose effectiveness will only be known after all construction is completed. One of the challenges of large basin management is the optimization of water use through ongoing regional economic development, droughts, and climate change. This paper describes a model of the Savannah River Basin designed to continuously optimize regulated flow to meet prioritized objectives set by resource managers and stakeholders. The model was developed from historical data using machine learning, making it more accurate and adaptable to changing conditions than traditional models. The model is coupled to an optimization routine that computes the daily flow needed to most efficiently meet the water-resource management objectives. The model and optimization routine are packaged in a decision support system that makes it easy for managers and stakeholders to use. Simulation results show that flow can be regulated to substantially reduce salinity intrusions in the Savannah National Wildlife Refuge, while conserving more water in the reservoirs. A method for using the model to assess the effectiveness of the flow-alteration features after the deepening also is demonstrated.

Georgia, North Carolina, South Carolina↗

USGS2010

CORSSA: The Community Online Resource for Statistical Seismicity Analysis

Statistical seismology is the application of rigorous statistical methods to earthquake science with the goal of improving our knowledge of how the earth works. Within statistical seismology there is a strong emphasis on the analysis of seismicity data in order to improve our scientific understanding of earthquakes and to improve the evaluation and testing of earthquake forecasts, earthquake early warning, and seismic hazards assessments. Given the societal importance of these applications, statistical seismology must be done well. Unfortunately, a lack of educational resources and available software tools make it difficult for students and new practitioners to learn about this discipline. The goal of the Community Online Resource for Statistical Seismicity Analysis (CORSSA) is to promote excellence in statistical seismology by providing the knowledge and resources necessary to understand and implement the best practices, so that the reader can apply these methods to their own research. This introduction describes the motivation for and vision of CORRSA. It also describes its structure and contents.

Community Online Resource for Statistical Seismici↗

USGS2015

Aniakchak National Monument and Preserve: Geologic resources inventory report

This GRI report is a companion document to previously completed GRI digital geologic map data. It was written for resource managers to support science-informed decision making. It may also be useful for interpretation. The report was prepared using available geologic information, and the NPS Geologic Resources Division conducted no new fieldwork in association with its preparation. Sections of the report discuss distinctive geologic features and processes within the park, highlight geologic issues facing resource managers, describe the geologic history leading to the present-day landscape, and provide information about the GRI geologic map data. A poster illustrates these data. The Map Unit Properties Table summarizes report content for each geologic map unit.

Alaska↗

USGS2016

Resource management and operations in central North Dakota: Climate change scenario planning workshop summary November 12-13, 2015, Bismarck, ND

The Scaling Climate Change Adaptation in the Northern Great Plains through Regional Climate Summaries and Local Qualitative-Quantitative Scenario Planning Workshops project synthesizes climate data into 3-5 distinct but plausible climate summaries for the northern Great Plains region; crafts quantitative summaries of these climate futures for two focal areas; and applies these local summaries by developing climate-resource-management scenarios through participatory workshops and, where possible, simulation models. The two focal areas are central North Dakota and southwest South Dakota (Figure 1). The primary objective of this project is to help resource managers and scientists in a focal area use scenario planning to make management and planning decisions based on assessments of critical future uncertainties. This report summarizes project work for public and tribal lands in the central North Dakota focal area, with an emphasis on Knife River Indian Villages National Historic Site. The report explains scenario planning as an adaptation tool in general, then describes how it was applied to the central North Dakota focal area in three phases. Priority resource management and climate uncertainties were identified in the orientation phase. Local climate summaries for relevant, divergent, and challenging climate scenarios were developed in the second phase. In the final phase, a two-day scenario planning workshop held November 12-13, 2015 in Bismarck, ND, featured scenario development and implications, testing management decisions, and methods for operationalizing scenario planning outcomes.

Natural Resource Report↗

USGS2016

Resource management and operations in southwest South Dakota: Climate change scenario planning workshop summary January 20-21, 2016, Rapid City, SD

The Scaling Climate Change Adaptation in the Northern Great Plains through Regional Climate Summaries and Local Qualitative-Quantitative Scenario Planning Workshops project synthesizes climate data into 3-5 distinct but plausible climate summaries for the northern Great Plains region; crafts quantitative summaries of these climate futures for two focal areas; and applies these local summaries by developing climate-resource-management scenarios through participatory workshops and, where possible, simulation models. The two focal areas are central North Dakota and southwest South Dakota (Figure 1). The primary objective of this project is to help resource managers and scientists in a focal area use scenario planning to make management and planning decisions based on assessments of critical future uncertainties. This report summarizes project work for public and tribal lands in the southwest South Dakota grasslands focal area, with an emphasis on Badlands National Park and Buffalo Gap National Grassland. The report explains scenario planning as an adaptation tool in general, then describes how it was applied to the focal area in three phases. Priority resource management and climate uncertainties were identified in the orientation phase. Local climate summaries for relevant, divergent, and challenging climate scenarios were developed in the second phase. In the final phase, a two-day scenario planning workshop held January 20-21, 2016 in Rapid City, South Dakota, featured scenario development and implications, testing management decisions, and methods for operationalizing scenario planning outcomes.

Natural Resource Report↗

USGS1985

Ground water in Utah - A summary description of the resource and its related physical environment

Ground water is one of Utah’s most extensive and valuable natural resources. Because of its widespread occurrence in both wet and dry areas, ground water has been, and is a major factor affecting economic growth and development of the State. In some areas, ground water is used to supplement streamflow for irrigation, public supply, and other uses. In other areas, it is the only water available for use. Many communities obtain their entire water supply from ground-water sources (wells and springs) as do numerous rural and suburban households throughout the State. The ground-water reservoirs of Utah contain tremendous quantities of water – many times more than the quantity stored in all the lakes (including Great Salt Lake) and the surface-water reservoirs of the State combined. Water that discharges from those underground reservoirs in seeps and springs is vital in sustaining the flow of streams during dry summer months and in providing the water needed to maintain important wetland habitats. Those same underground reservoirs also provide large quantities of water in carryover storage for use during prolonged droughts. The U.S. Geological survey, under cooperative programs with the Utah department of Natural resources and other Federal, State, and local agencies has been studying Utah’s ground-water resources since 1897. Much information has been gained during those studies about the occurrence, availability, and quality of ground water; the withdrawal and use of the water; and the effects of withdrawal. This report summarizes that information in nontechnical language, which is designed for all readers. Readers interested in more detailed information about ground water in specific areas of Utah are referred to the reports listed by LaPray and Hamblin (1980).

Utah↗

USGS2006

Heat flow in Railroad Valley, Nevada and implications for geothermal resources in the south-central Great Basin

The Great Basin is a province of high average heat flow (approximately 90 mW m -2 ), with higher values characteristic of some areas and relatively low heat flow (<60 mW m -2 ) characteristic of an area in south-central Nevada known as the Eureka Low. There is hydrologic and thermal evidence that the Eureka Low results from a relatively shallow, hydrologically controlled heat sink associated with interbasin water flow in the Paleozoic carbonate aquifers. Evaluating this hypothesis and investigating the thermal state of the Eureka Low at depth is a high priority for the US Geological Survey as it prepares a new national geothermal resource assessment. Part of this investigation is focused on Railroad Valley, the site of the largest petroleum reservoirs in Nevada and one of the few locations within the Eureka Low with a known geothermal system. Temperature and thermal conductivity data have been acquired from wells in Railroad Valley in order to determine heat flow in the basin. The results reveal a complex interaction of cooling due to shallow ground-water flow, relatively low (49 to 76 mW m -2 ) conductive heat flow at depth in most of the basin, and high (up to 234 mW m -2 ) heat flow associated with the 125°C geothermal system that encompasses the Bacon Flat and Grant Canyon oil fields. The presence of the Railroad Valley geothermal resource within the Eureka Low may be reflect the absence of deep ground-water flow sweeping heat out of the basin. If true, this suggests that other areas in the carbonate aquifer province may contain deep geothermal resources that are masked by ground-water flow.

Nevada↗

USGS2024

Writing SMART objectives for natural resource and environmental management

In natural resource and environmental management, well-written objectives are critical for effective decision-making and the achievement of desired outcomes. This article aims to improve practitioners' ability to identify and write SMART ( S pecific, M easurable, A chievable, R elevant, T ime-bound) objectives for natural resource and environmental management. We differentiate between research and management objectives, define each SMART criterion, and introduce a template to help write management objectives. We demonstrate the use of the SMART management objectives template with a hypothetical example and two recent applications. The template simplifies the process of writing SMART management objectives. It is applicable to popular management frameworks like management by objectives and structured decision making. The implementation of SMART criteria and the provided template can lead to better outcomes in natural resource and environmental management, benefiting current and future generations.

Ecological Solutions and Evidence↗

USGS2023

Provenance, genotype, and flooding influence growth and resource acquisition characteristics in a clonal, riparian shrub

Premise Riparian plants can exhibit intraspecific phenotypic variability across the landscape related to temperature and flooding gradients. Phenotypes that vary across a climate gradient are often partly genetically determined and may differ in their response to inundation. Changes to inundation patterns across a climate gradient could thus result in site-specific inundation responses. Phenotypic variability is more often studied in riparian trees, yet riparian shrubs are key elements of riparian systems and may differ from trees in phenotypic variability and environmental responses. Methods We tested if individuals of a clonal, riparian shrub, Pluchea sericea , collected from provenances spanning a temperature gradient differed in their phenotypes and responses to inundation and to what degree such differences were related to genotype. Plants were subjected to different inundation depths and a subset genotyped. Variables related to growth and resource acquisition were measured and analyzed using hierarchical, multivariate Bayesian linear regressions. Results Individuals from different provenances differed in their phenotypes, but not in their response to inundation. Phenotypes were not related to provenance temperature but were partially governed by genotype. Growth was more strongly influenced by inundation, while resource acquisition was more strongly controlled by genotype. Conclusions Growth and resource acquisition responses in a clonal, riparian shrub are affected by changes to inundation and plant demographics in unique ways. Shrubs appear to differ from trees in their responses to environmental change. Understanding environmental effects on shrubs separately from those of trees will be a key part of evaluating environmental change impacts on riparian ecosystems.

American Journal of Botany↗