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At least 1,081 records · Page 60Linked to original sources
USGS2025

Comparison of hydrologic data and water budgets between 2003–08 and 2018–23 for the eastern part of the Arbuckle-Simpson aquifer, south-central Oklahoma

The Arbuckle-Simpson aquifer is divided spatially into three parts (eastern, central, and western). The largest groundwater withdrawals are from the eastern part of the Arbuckle-Simpson aquifer, which provides water to approximately 39,000 people in Ada and Sulphur, Oklahoma, and surrounding areas. The Arbuckle-Simpson aquifer, including the eastern part, is designated a sole source aquifer for its service area. Based primarily on data collected between 2003 and 2008, a series of comprehensive hydrologic studies of the Arbuckle-Simpson aquifer was published to provide the information necessary to perform groundwater-flow model simulations so that the Oklahoma Water Resources Board could determine how much water could be withdrawn from the aquifer while maintaining flow to springs and streams. As part of the Phase 1 studies, an aquifer water budget was developed from a numerical model for the period 2003–08. For this report, Phase 1 refers to the 2003–08 data collection period, although for some of the analyses, data collected prior to 2003 were used to inform model development work. Allocation of water from this aquifer was then established by the Oklahoma Water Resources Board in 2013. Additional well-spacing rules were also established by the Oklahoma Water Resources Board for sensitive sole source groundwater basins. To determine how the water budget for the eastern part of the Arbuckle-Simpson aquifer has changed over time, recently collected hydrologic data (2018–23) were compared to data collected during 2003–08. The analysis of changes in the aquifer water budget from 2003–08 to 2018–23 could help resource managers better understand changes in the overall balance of water in storage and the potential effects on streamflow, changes in groundwater levels, and the effects of different water uses in the aquifer area on available water in the eastern part of the Arbuckle-Simpson aquifer and streams overlying the eastern part of the Arbuckle-Simpson aquifer.

Oklahoma↗
USGS2026

Salinas Valley integrated hydrologic and reservoir operations models, Monterey and San Luis Obispo Counties, California

The area surrounding the Salinas Valley groundwater basin in Monterey and San Luis Obispo Counties of California is a highly productive agricultural area, contributes substantially to the local economy, and provides a substantial portion of vegetables and other agricultural commodities to the Nation. This region of California provides about half of the Nation’s lettuce, celery, broccoli, and spinach each year. Thus, this agricultural area provides substantial volumes of agricultural products not just for California but for the United States. Changes in population and increased agricultural development, which includes a shift toward more water-intensive crops, and climate variability, have put increasing demand on both surface-water and groundwater resources in the valley. This situation has resulted in water management challenges in the Salinas Valley that generally relate to the distribution of the water supply throughout the basin. Where and when the water is present in the surface and subsurface does not coincide with where and when the water is needed. Historically, to deal with the distribution issue, water has been used conjunctively in the valley. Conjunctive use is a water management strategy that coordinates surface-water and groundwater use to maximize water availability. Groundwater is used throughout the Salinas Valley to meet water demands when surface-water supplies are insufficient. The availability of surface water is constrained by climate. Precipitation and streamflow vary seasonally and year to year. Although there are two reservoirs in the Salinas Valley to capture and store water during wet periods, the only conveyance of reservoir water to coastal agricultural areas is the Salinas River. Increasing demand for groundwater and surface-water resources throughout the Salinas Valley has resulted in undesirable effects from unsustainable water use, such as surface-water depletion, groundwater-level declines, storage depletion in the principal aquifers, and seawater intrusion. To address these escalating issues, local communities, water management agencies, and groundwater sustainability agencies are evaluating how to sustainably manage both their surface-water and groundwater resources. To meet water demands and reduce the undesirable effects of unsustainable water use, continued conjunctive management of surface water and groundwater would ideally incorporate strategies to deal with increases in demand and climate variability. To evaluate the challenging water management issues in the Salinas Valley, the U.S. Geological Survey, Monterey County Water Resources Agency, and the Salinas Valley Basin Groundwater Sustainability Agency developed a comprehensive suite of models that represent the Salinas Valley hydrogeologic system called the Salinas Valley System Model. The geologic framework is known as the Salinas Valley Geologic Framework and was developed to characterize the subsurface using various topographic and geologic data sources, including information on hydrogeologic units, their surfaces and extents, geologic structures, lithology, and elevations from borehole data and cross sections, as well as details on faults and existing models. The surface-water model is called the Salinas Valley Watershed Model and simulates the Salinas River watershed. Monthly surface-water inflows into the integrated hydrologic model domain were simulated using the Salinas Valley Watershed Model. The historical model uses historical climate data, water and land use data, and reservoir releases to simulate agricultural operations, including landscape water demands, diversions, and reclaimed wastewater. The operational model adds an embedded reservoir operations framework to the simulation of the historical model that allows specified operational rules to simulate reservoir releases and changes in reservoir storage. The operational model assumes current reservoir operations and constant land use, which differs from historical conditions. Thus, the operational model is a hypothetical baseline model that can be used by local water managers to evaluate and quantify potential benefits of water supply projects. Together, the geologic framework, watershed, historical, and operational models form a tool that can be used to simulate irrigated agriculture and associated reservoir operations of the integrated hydrologic system of the Salinas Valley.

California↗
USGS2015

U.S. Geological Survey groundwater toolbox, a graphical and mapping interface for analysis of hydrologic data (version 1.0): user guide for estimation of base flow, runoff, and groundwater recharge from streamflow data

This report is a user guide for the streamflow-hydrograph analysis methods provided with version 1.0 of the U.S. Geological Survey (USGS) Groundwater Toolbox computer program. These include six hydrograph-separation methods to determine the groundwater-discharge (base-flow) and surface-runoff components of streamflow—the Base-Flow Index (BFI; Standard and Modified), HYSEP (Fixed Interval, Sliding Interval, and Local Minimum), and PART methods—and the RORA recession-curve displacement method and associated RECESS program to estimate groundwater recharge from streamflow data. The Groundwater Toolbox is a customized interface built on the nonproprietary, open source MapWindow geographic information system software. The program provides graphing, mapping, and analysis capabilities in a Microsoft Windows computing environment. In addition to the four hydrograph-analysis methods, the Groundwater Toolbox allows for the retrieval of hydrologic time-series data (streamflow, groundwater levels, and precipitation) from the USGS National Water Information System, downloading of a suite of preprocessed geographic information system coverages and meteorological data from the National Oceanic and Atmospheric Administration National Climatic Data Center, and analysis of data with several preprocessing and postprocessing utilities. With its data retrieval and analysis tools, the Groundwater Toolbox provides methods to estimate many of the components of the water budget for a hydrologic basin, including precipitation; streamflow; base flow; runoff; groundwater recharge; and total, groundwater, and near-surface evapotranspiration.

Techniques and Methods↗
USGS2014

HydroClimATe: hydrologic and climatic analysis toolkit

The potential consequences of climate variability and climate change have been identified as major issues for the sustainability and availability of the worldwide water resources. Unlike global climate change, climate variability represents deviations from the long-term state of the climate over periods of a few years to several decades. Currently, rich hydrologic time-series data are available, but the combination of data preparation and statistical methods developed by the U.S. Geological Survey as part of the Groundwater Resources Program is relatively unavailable to hydrologists and engineers who could benefit from estimates of climate variability and its effects on periodic recharge and water-resource availability. This report documents HydroClimATe, a computer program for assessing the relations between variable climatic and hydrologic time-series data. HydroClimATe was developed for a Windows operating system. The software includes statistical tools for (1) time-series preprocessing, (2) spectral analysis, (3) spatial and temporal analysis, (4) correlation analysis, and (5) projections. The time-series preprocessing tools include spline fitting, standardization using a normal or gamma distribution, and transformation by a cumulative departure. The spectral analysis tools include discrete Fourier transform, maximum entropy method, and singular spectrum analysis. The spatial and temporal analysis tool is empirical orthogonal function analysis. The correlation analysis tools are linear regression and lag correlation. The projection tools include autoregressive time-series modeling and generation of many realizations. These tools are demonstrated in four examples that use stream-flow discharge data, groundwater-level records, gridded time series of precipitation data, and the Multivariate ENSO Index.

Techniques and Methods↗
USGS1968

Some statistical tools in hydrology

This chapter of 'Techniques of Water-Resources Investigations' provides background material needed for understanding the statistical procedures most useful in hydrology; it furnishes detailed procedures, with examples, of regression analyses; it describes analysis of variance and covariance and discusses the characteristics of hydrologic data.

Techniques of Water-Resources Investigations↗
USGS2000

Hydrology, water quality, and nutrient loads to Lake Catherine and Channel Lake, near Antioch, Lake County, Illinois

From April 21, 1998, through April 30, 1999, the U.S. Geological Survey, in cooperation with the Fox Waterway Agency, conducted an investigation designed to characterize the hydrology, water quality, hydrologic budget, sediment budget, and nutrient budget of Lake Catherine and Channel Lake, Lake County, Illinois. These lakes are the northernmost lakes of the Fox Chain of Lakes. Lake Catherine and Channel Lake are divided into two basins by a submerged ridge but are continuous at the surface. The lakes are marginally to moderately eutrophic. Lake Catherine and Channel Lake have a combined volume of 7,098 acre-feet at a stage of about 736.5 feet above sea level. Lake Catherine and Channel Lake are subject to thermal stratification. Although most of the water in the lakes is well oxidized, nearly anoxic conditions were present at the bottom of Lake Catherine and Channel Lake during part of the summer in 1998. Water enters Lake Catherine and Channel Lake as inflow from surface water in the watershed (61.9 percent), inflow through the State Highway 173 bridge openings (20.7 percent), direct precipitation (8.2 percent), inflow from storm drains (7.2 percent), and inflow of ground water (2.0 percent). Water exits Lake Catherine and Channel Lake as outflow through the State Highway 173 bridge openings (87.8 percent), evaporation (7.2 percent), and as outflow to ground water (5.0 percent). About 5,200 pounds of phosphorus and 107,200 pounds of nitrogen compounds were added to the lakes during the period of investigation. Phosphorus compounds were derived from primarily internal regeneration (40.2 percent), inflow from surface water in the watershed (30.9 percent), inflow from storm drains (12.5 percent), and inflow through the State Highway 173 bridge openings (9.8 percent). Inflowing ground water, waterfowl excrement, precipitation, and atmospheric deposition of particulate matter account for 6.6 percent of the phosphorus load. Nitrogen was derived from inflow of surface water from within the watershed (52.9 percent), internal regeneration (19.5 percent), inflow through the State Highway 173 bridge openings (10.7 percent), precipitation (7 percent), and inflow from storm drains (6.5 percent). Inflowing ground water, waterfowl excrement, and atmospheric deposition of particulate matter account for about 3.4 percent of the nitrogen load. About 2,220 pounds of phosphorus and 52,300 pounds of nitrogen compounds are removed from the lakes, primarily through the openings at State Highway 173. Nitrate, nitrite, ammonia, and dissolved phosphorus are utilized by algae and aquatic macrophytes. Uptake of these nutrients by aquatic macrophytes and algae temporarily removes them from the water column but not from the lake basin. Because the amount of nutrients entering the lake greatly exceeds the amount leaving, the nutrients are concentrated in the sediments at the lake bottom, where the nutrients can be used by the rooted aquatic macrophytes (rooted aquatic plant large enough to be visible to the unaided eye) and released to the water column during reducing conditions. The buildup of nitrogen and phosphorus compounds in the lakes has the potential over time to stimulate algal and plant growth to nuisance levels that have the potential to affect the fishery and detract from the aesthetic quality of these lakes.

Water-Resources Investigations Report↗
USGS2002

Hydrologic investigation of Powell Marsh and its relation to Dead Pike Lake, Vilas County, Wisconsin

An analytic element ground-water-flow model was constructed to help understand the ground- and surface-water hydrology in the vicinity of Dead Pike Lake and Powell Marsh, Vilas County, Wisconsin. The model was used to simulate the effect of removing Powell Marsh control structures (ditches and Vista Pond) on the hydrology of Dead Pike Lake. Measurements and model simulation results show that ground water in the vicinity of Powell Marsh moves to the northwest and west. If Powell Marsh structures are removed from the simulation, it does not affect the general direction of ground-water flow nor the total flow to Dead Pike Lake. Without the simulated structures, slightly more ground-water flow enters Dead Pike Lake and slightly less surface-water flows at the Dead Pike Lake inlet than with the simulated structures. Ground-water levels measured in piezometers installed along a flow path indicated that ground-water flow primarily is horizontal in the marsh and moves upward in the vicinity of a ditch where it discharges. Flow from Vista Pond is downward to the ground-water system but eventually also discharges upward to the ditches. Based on analyses of water samples from piezometers, the ditch, and Vista Pond, it was shown that dissolved iron is transported in the ground water. When ground water is discharged, iron and manganese react with dissolved oxygen, then precipitates, and forms the oxyhydroxide floc present in the Powell Marsh ditches. The processes involved in the transport and floc formation are not unique to the ditches, but are an expected outcome where discharging ground water and oxygenated surface water meet. Therefore, although floc formed in the ditches would no longer be available for transport if ditches were removed, it is likely that the floc formation would be redirected to the near-shore areas of Dead Pike Lake where increased groundwater discharge is expected.

Wisconsin↗
USGS2002

Hydrologic trends associated with urban development for selected streams in the Puget Sound basin, western Washington

Annual streamflow statistics from 10 selected streams in the Puget Sound Basin in western Washington were analyzed to identify possible hydrologic trends associated with urban development and to evaluate the effect of record length on errors in trend analysis. The analysis used three common streamflow statistics (annual mean discharge, annual maximum discharge, and 7-day low flow) and introduced an alternative statistic (fraction of year annual mean discharge was exceeded) for assessing the hydrologic effects of urban development. Although trends were identified in each of the four statistics analyzed, trends were not consistent in any of the four statistics for all selected streams. Instead, trends in two statistics ? (1) fraction of year annual mean discharge was exceeded, and (2) annual (instantaneous) maximum discharge ? were evident in streams with the highest levels of urban development over the period of record but not in streams with the lowest levels of urban development. Trends were not consistent for either annual mean discharge or 7-day low flow in urban streams. Trends were sensitive to the period of analysis for all four statistics, but particularly for the 7-day low flow, which showed increasing and decreasing trends for 10 subsets of the period of record in some streams.

Water-Resources Investigations Report↗
USGS2003

Analytical and numerical simulation of the steady-state hydrologic effects of mining aggregate in hypothetical sand-and-gravel and fractured crystalline-rock aquifers

Analytical solutions and numerical models were used to predict the extent of steady-state drawdown caused by mining of aggregate below the water table in hypothetical sand-and-gravel and fractured crystalline-rock aquifers representative of hydrogeologic settings in the Front Range area of Colorado. Analytical solutions were used to predict the extent of drawdown under a wide range of hydrologic and mining conditions that assume aquifer homogeneity, isotropy, and infinite extent. Numerical ground-water flow models were used to estimate the extent of drawdown under conditions that consider heterogeneity, anisotropy, and hydrologic boundaries and to simulate complex or unusual conditions not readily simulated using analytical solutions. Analytical simulations indicated that the drawdown radius (or distance) of influence increased as horizontal hydraulic conductivity of the aquifer, mine penetration of the water table, and mine radius increased; radius of influence decreased as aquifer recharge increased. Sensitivity analysis of analytical simulations under intermediate conditions in sand-and-gravel and fractured crystalline-rock aquifers indicated that the drawdown radius of influence was most sensitive to mine penetration of the water table and least sensitive to mine radius. Radius of influence was equally sensitive to changes in horizontal hydraulic conductivity and recharge. Numerical simulations of pits in sand-and- gravel aquifers indicated that the area of influence in a vertically anisotropic sand-and-gravel aquifer of medium size was nearly identical to that in an isotropic aquifer of the same size. Simulated area of influence increased as aquifer size increased and aquifer boundaries were farther away from the pit, and simulated drawdown was greater near the pit when aquifer boundaries were close to the pit. Pits simulated as lined with slurry walls caused mounding to occur upgradient from the pits and drawdown to occur downgradient from the pits. Pits simulated as refilled with water and undergoing evaporative losses had little hydro- logic effect on the aquifer. Numerical sensitivity analyses for simulations of pits in sand-and-gravel aquifers indicated that simulated head was most sensitive to horizontal hydraulic conductivity and the hydraulic conductance of general-head boundaries in the models. Simulated head was less sensitive to riverbed conductance and recharge and relatively insensitive to vertical hydraulic conductivity. Numerical simulations of quarries in fractured crystalline-rock aquifers indicated that the area of influence in a horizontally anisotropic aquifer was elongated in the direction of higher horizontal hydraulic conductivity and shortened in the direction of lower horizontal hydraulic conductivity compared to area of influence in a homogeneous, isotropic aquifer. Area of influence was larger in an aquifer with ground-water flow in deep, low-permeability fractures than in a homogeneous, isotropic aquifer. Area of influence was larger for a quarry intersected by a hydraulically conductive fault zone and smaller for a quarry intersected by a low-conductivity fault zone. Numerical sensitivity analyses for simulations of quarries in fractured crystalline-rock aquifers indicated simulated head was most sensitive to variations in recharge and horizontal hydraulic conductivity, had little sensitivity to vertical hydraulic conductivity and drain cells used to simulate valleys, and was relatively insensitive to drain cells used to simulate the quarry.

Water-Resources Investigations Report↗
USGS2003

Development, calibration, and analysis of a hydrologic and water-quality model of the Delaware Inland Bays watershed

Excessive nutrients and sediment are among the most significant environmental stressors in the Delaware Inland Bays (Rehoboth, Indian River, and Little Assawoman Bays). Sources of nutrients, sediment, and other contaminants within the Inland Bays watershed include point-source discharges from industries and wastewater-treatment plants, runoff and infiltration to ground water from agricultural fields and poultry operations, effluent from on-site wastewater disposal systems, and atmospheric deposition. To determine the most effective restoration methods for the Inland Bays, it is necessary to understand the relative distribution and contribution of each of the possible sources of nutrients, sediment, and other contaminants. A cooperative study involving the Delaware Department of Natural Resources and Environmental Control, the Delaware Geological Survey, and the U.S. Geological Survey was initiated in 2000 to develop a hydrologic and water-quality model of the Delaware Inland Bays watershed that can be used as a water-resources planning and management tool. The model code Hydrological Simulation Program - FORTRAN (HSPF) was used. The 719-square-kilometer watershed was divided into 45 model segments, and the model was calibrated using streamflow and water-quality data for January 1999 through April 2000 from six U.S. Geological Survey stream-gaging stations within the watershed. Calibration for some parameters was accomplished using PEST, a model-independent parameter estimator. Model parameters were adjusted systematically so that the discrepancies between the simulated values and the corresponding observations were minimized. Modeling results indicate that soil and aquifer permeability, ditching, dominant land-use class, and land-use practices affect the amount of runoff, the mechanism or flow path (surface flow, interflow, or base flow), and the loads of sediment and nutrients. In general, the edge-of-stream total suspended solids yields in the Inland Bays watershed are low in comparison to yields reported for the Eastern Shore from the Chesapeake Bay watershed model. The flatness of the terrain and the low annual surface runoff are important factors in determining the amount of detached sediment from the land that is delivered to streams. The highest total suspended solids yields were found in the southern part of the watershed, associated with high total streamflow and a high surface runoff component, and related to soil and aquifer permeability and land use. Nutrient yields from watershed model segments in the southern part of the Inland Bays watershed were the highest of all calibrated segments, due to high runoff and the substantial amount of available organic fertilizer (animal waste), which results in over-application of organic fertilizer to crops. Time series of simulated hourly total nitrogen concentrations and observed instantaneous values indicate a seasonal pattern, with the lowest values occurring during the summer and the highest during the winter months. Total phosphorus and total suspended solids concentrations are somewhat less seasonal. During storm events, total nitrogen concentrations tend to be diluted and total phosphorus concentrations tend to rise sharply. Nitrogen is transported mainly in the aqueous phase and primarily through ground water, whereas phosphorus is strongly associated with sediment, which washes off during precipitation events.

Water-Resources Investigations Report↗
USGS2003

Hydrologic and Hydraulic Analyses of Selected Streams in Lorain County, Ohio, 2003

Hydrologic and hydraulic analyses were done for selected reaches of nine streams in Lorain County Ohio. To assess the alternatives for flood-damage mitigation, the Lorain County Engineer and the U.S. Geological Survey (USGS) initiated a cooperative study to investigate aspects of the hydrology and hydraulics of the nine streams. Historical streamflow data and regional regression equations were used to estimate instantaneous peak discharges for floods having recurrence intervals of 2, 5, 10, 25, 50, and 100 years. Explanatory variables used in the regression equations were drainage area, main-channel slope, and storage area. Drainage areas of the nine stream reaches studied ranged from 1.80 to 19.3 square miles. The step-backwater model HEC-RAS was used to determine water-surface-elevation profiles for the 10-year-recurrence-interval (10-year) flood along a selected reach of each stream. The water-surface pro-file information was used then to generate digital mapping of flood-plain boundaries. The analyses indicate that at the 10-year flood elevation, road overflow results at numerous hydraulic structures along the nine streams.

Water-Resources Investigations Report↗
USGS2000

Hydrologic treatments affect gaseous carbon loss From organic soils, Twitchell Island, California, October 1995–December 1997

Subsidence of organic soils in the Sacramento-San Joaquin Delta, California, has increased the potential for levee failure and flooding in the region. Because oxidation of the peat soils is a primary cause of subsidence, reversion of affected lands to wetlands has been proposed as a mitigation tool. To test this hypothesis, three 10 x 10 meter enclosures were built on Twitchell Island in the Delta and managed as different wetland habitats. Emissions of carbon dioxide and methane were measured in situ from October 1995 through December 1997, from the systems that developed under the different water-management treatments. Treatments included a seasonal control (SC) under current island management conditions; reverse flooding (RF), where the land is intentionally flooded from early dry season until midsummer; permanent shallow flooding (F); and a more deeply flooded, open-water (OW) treatment. Hydrologic treatments affected microbial processes, plant community and temperature dynamics which, in turn, affected carbon cycling. Water-management treatments with a period of flooding significantly decreased gaseous carbon emissions compared to the seasonal control. Permanent flooding treatments showed significantly higher methane fluxes than treatments with some period of aerobic conditions. Shallow flooding treatments created conditions that support cattail [Typha species (spp.)] marshes, while deep flooding precluded emergent vegetation. Carbon inputs to the permanent shallow flooding treatment tended to be greater than the measured losses. This suggests that permanent shallow flooding has the greatest potential for managing subsidence of these soils by generating organic substrate more rapidly than is lost through decomposition. Carbon input estimates of plant biomass compared to measurements of gaseous carbon losses indicate the potential for mitigation of subsidence through hydrologic management of the organic soils in the area.

California↗
USGS2001

Ground-Water Hydrology of the Upper Deschutes Basin, Oregon

The upper Deschutes Basin is among the fastest growing regions in Oregon. The rapid population growth has been accompanied by increased demand for water. Surface streams, however, have been administratively closed to additional appropriation for many years, and surface water is not generally available to support new development. Consequently, ground water is being relied upon to satisfy the growth in water demand. Oregon water law requires that the potential effects of ground-water development on streamflow be evaluated when considering applications for new ground-water rights. Prior to this study, hydrologic understanding has been insufficient to quantitatively evaluate the connection between ground water and streamflow, and the behavior of the regional ground-water flow system in general. This report describes the results of a hydrologic investigation undertaken to provide that understanding. The investigation encompasses about 4,500 square miles of the upper Deschutes River drainage basin.A large proportion of the precipitation in the upper Deschutes Basin falls in the Cascade Range, making it the principal ground-water recharge area for the basin. Water-balance calculations indicate that the average annual rate of ground- water recharge from precipitation is about 3,500 ft3/s (cubic feet per second). Water-budget calculations indicate that in addition to recharge from precipitation, water enters the ground-water system through interbasin flow. Approximately 800 ft3/s flows into the Metolius River drainage from the west and about 50 ft3/s flows into the southeastern part of the study area from the Fort Rock Basin. East of the Cascade Range, there is little or no ground-water recharge from precipitation, but leaking irrigation canals are a significant source of artificial recharge north of Bend. The average annual rate of canal leakage during 1994 was estimated to be about 490 ft3/s. Ground water flows from the Cascade Range through permeable volcanic rocks eastward out into the basin and then generally northward. About one-half the ground water flowing from the Cascade Range discharges to spring-fed streams along the margins of the range, including the upper Metolius River and its tributaries. The remaining ground water flows through the subsurface, primarily through rocks of the Deschutes Formation, and eventually discharges to streams near the confluence of the Deschutes, Crooked, and Metolius Rivers. Substantial ground-water discharge occurs along the lower 2 miles of Squaw Creek, the Deschutes River between Lower Bridge and Pelton Dam, the lower Crooked River between Osborne Canyon and the mouth, and in Lake Billy Chinook (a reservoir that inundates the confluence of the Deschutes, Crooked, and Metolius Rivers).The large amount of ground-water discharge in the confluence area is primarily caused by geologic factors. North (downstream) of the confluence area, the upper Deschutes Basin is transected by a broad region of low-permeability rock of the John Day Formation. The Deschutes River flows north across the low-permeability region, but the permeable Deschutes Formation, through which most of the regional ground water flows, ends against this rampart of low-permeability rock. The northward-flowing ground water discharges to the streams in this area because the permeable strata through which it flows terminate, forcing the water to discharge to the surface. Virtually all of the regional ground water in the upper Deschutes Basin discharges to surface streams south of the area where the Deschutes River enters this low-permeability terrane, at roughly the location of Pelton Dam.The effects of ground-water withdrawal on streamflow cannot presently be measured because of measurement error and the large amount of natural variability in ground-water discharge. The summer streamflow near Madras, which is made up largely of ground-water discharge, is approximately 4,000 ft3/s. Estimated consumptive ground-water use in the basin i

Water-Resources Investigations Report↗
USGS1976

Summary of some current and possible future environmental problems related to geology and hydrology at Memphis, Tennessee

Memphis, Tennessee, like many other cities in the Nation, has some problems related to local geology and hydrology. The city is in the Coastal Plain physiographic province and is underlain at shallow depths by sand, clay, silt, gravel, and lignite. These post-Midway strata (Wilcox and younger) make up geologic units belonging to the uppermost Paleocene, Eocene, and Pliocene (?) Series of the Tertiary System and to the Pleistocene and Holocene Series of the Quaternary System. Environmental problems of immediate or future concern are associated with six general topics: (1) aggregate resources, (2) foundation materials, (3) earthquake hazards, (4) flood hazards, (5) water resources, and (6) solid waste disposal. Consideration of these topics in one report should provide an overall insight into the close interrelation of the problems and the need for coordinated studies of the geology and hydrology at Memphis.

Tennessee↗
USGS1976

Effects of off-road vehicle use on the hydrology and landscape of arid environments in central and southern California

Two widely separated sites in California used for motorcycle hill-climbing were studied to evaluate the impact on the landscape and hydrology. At Panoche Hills in central California, an area formerly used by motorcycles together with an adjacent unused area were monitored from 1971 to 1975. Observations in both areas included measurements of precipitation, runoff, soil moisture, soil bulk density, plant cover, and erosion surveys. At Dove Spring Canyon in southern California erosion was measured on a site that is currently being used for motorcycle hill-climbing. At the Panoche Hills site, the area used by motorcycles produced about eight times as much runoff as the unused area. Similarly, sediment yield from the used areas was 857 cubic meters/sq km, while the quantity of sediment from the unused area was not measurable by standard methods. At the Dove Spring Canyon site, which is still being used for hill-climbing, erosion surveys show that degradation in trails has been as much as 0.3 m in the period 1973-75. Compaction of soils and reduction of permeability appears to be the most serious hydrologic impact of motorcycle use at Panoche Hills. Increased bulk density of soils reduces depth of moisture penetration which deprives plants of moisture needed for growth. (Woodard-USGS)

California↗
USGS1977

Hydrologic considerations associated with dredging spring ponds in Wisconsin

Spring ponds (small spring-fed bodies of water) are natural features of some glaciated areas and have a continuous flow of ground water entering through their bottoms and exiting through surface outlets. Dredging has been used to restore ponds that have been filled in part or totally by sediment. The purpose of the study was to determine the hydrology of selected spring ponds and the effect that dredging has had on the ponds. Three ponds, Maxwell, Sunshine, and Krause Ponds, in northeastern Wisconsin were studied. Sediments were dredged from Sunshine and Krause Ponds. Maxwell Pond, which was not dredged, was a hydrologic control to aid in distinguishing changes produced by dredging from those that were natural. Ground water from glacial deposits is the source of most of the water flowing in spring ponds and streams in the study area. Average annual ground-water recharge in the study area is about 13 inches. Ground-water discharge contributed 97 percent of the total flow in the Red River, a typical stream in the study area, during the 1973 water year. Ground water and surface water in the study area are of a calcium magnesium bicarbonate type. Dissolved-solids concentration ranges from 170 to 250 milligrams per liter. Temperature of ground water discharging into the spring ponds in the study ranged from 6 to 7 Celsius.

Wisconsin↗
USGS1977

Hydrology of the Creeping Swamp Watershed, North Carolina with reference to potential effects of stream channelization

Hydrologic data were collected for four years at six sites in the Creeping Swamp watershed in eastern North Carolina in a preliminary effort to study the effects of stream channelization on the hydrology of a small watershed. A water-budget evaluation for pre-channelized conditions showed that runoff accounts for about 17 percent of the total rainfall, base runoff about 20 percent, ground-water outflow about 2 percent, and evapotranspiration about 61 percent. Channelization would have caused the greatest decline in ground-water levels nearest the stream, with the decline diminishing with increased distance from the stream. Channelization would also have resulted in a decrease in overland runoff and an increase in the amount of water reaching Creeping Swamp through the ground-water system, although the total volume of runoff would not change significantly. The water-quality characteristics of Creeping Swamp indicate that the stream is relatively free of pollution, although it is likely that channelization would increase (1) suspended-sediment loads, (2) stream temperatures, and (3) concentrations of dissolved solids, especially during low flows.

North Carolina↗
USGS1978

Impact of potential phosphate mining on the hydrology of Osceola National Forest, Florida

Potentially exploitable phosphate deposits underlie part of Osceola National Forest, Fla. Hydrologic conditions in the forest are comparable with those in nearby Hamilton County, where phosphate mining and processing have been ongoing since 1965. Given similarity of operations, hydroloigc effects of mining in the forest are predicted. Flow of stream receiving phosphate industry effluent would increase somewhat during mining, but stream quality would not be greatly affected. Local changes in the configuration of the water table and the quality of water in the surficial aquifer will occur. Lowering of the potentiometric surface of the Floridan aquifer because of proposed pumpage would be less than five feet at nearby communities. Flordian aquifer water quality would be appreciably changed only if industrial effluent were discharged into streams which recharge the Flordian through sinkholes. The most significant hydrologic effects would occur at the time of active mining: long-term effects would be less significant.

Florida↗