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At least 1,333 records · Page 74Linked to original sources
USGS2004

Geochemistry of mine waste and mill tailings, meadow deposits, streambed sediments, and the general hydrology and water quality for the Frohner Meadows area, upper Lump Gulch, Jefferson County, Montana

Frohner Meadows, an area of low-topographic gradient subalpine ponds and wetlands in glaciated terrane near the headwaters of Lump Gulch (a tributary of Prickly Pear Creek), is located about 15 miles west of the town of Clancy, Montana, in the Helena National Forest. Mining and ore treatment of lead-zinc-silver veins in granitic rocks of the Boulder batholith over the last 120 years from two sites (Frohner mine and the Nellie Grant mine) has resulted in accumulations of mine waste and mill tailings that have been distributed downslope and downstream by anthropogenic and natural processes. This report presents the results of an investigation of the geochemistry of the wetlands, streams, and unconsolidated-sediment deposits and the hydrology, hydrogeology, and water quality of the area affected by these sources of ore-related metals. Ground water sampled from most shallow wells in the meadow system contained high concentrations of arsenic, exceeding the Montana numeric water-quality standard for human health. Transport of cadmium and zinc in ground water is indicated at one site near Nellie Grant Creek based on water-quality data from one well near the creek. Mill tailings deposited in upper Frohner Meadow contribute large arsenic loads to Frohner Meadows Creek; Nellie Grant Creek contributes large arsenic, cadmium, and zinc loads to upper Frohner Meadows. Concentrations of total-recoverable cadmium, copper, lead, and zinc in most surface-water sites downstream from the Nellie Grant mine area exceeded Montana aquatic-life standards. Nearly all samples of surface water and ground water had neutral to slightly alkaline pH values. Concentrations of arsenic, cadmium, lead, and zinc in streambed sediment in the entire meadow below the mine waste and mill tailings accumulations are highly enriched relative to regional watershed-background concentrations and exceed consensus-based, probable-effects concentrations for streambed sediment at most sites. Cadmium, copper, and zinc typically are adsorbed to the surface coatings of streambed-sediment grains. Mine waste and mill tailings contain high concentrations of arsenic, cadmium, copper, lead, and zinc in a quartz-rich matrix. Most of the waste sites that were sampled had low acid-generating capacity, although one site (fine-grained mill tailings from the Nellie Grant mine deposited in the upper part of lower Frohner Meadows) had extremely high acid-generating potential because of abundant fine-grained pyrite. Two distinct sites were identified as metal sources based on streambed-sediment samples, cores in the meadow substrate, and mine and mill-tailings samples. The Frohner mine and mill site contribute material rich in arsenic and lead; similar material from the Nellie Grant mine and mill site is rich in cadmium and zinc.

Montana↗
USGS2004

Hydrologic data summary for the St. Lucie River Estuary, Martin and St. Lucie Counties, Florida, 1998-2001

A hydrologic analysis was made at three canal sites and four tidal sites along the St. Lucie River Estuary in southeastern Florida from 1998 to 2001. The data included for analysis are stage, 15-minute flow, salinity, water temperature, turbidity, and suspended-solids concentration. During the period of record, the estuary experienced a drought, major storm events, and high-water discharge from Lake Okeechobee. Flow mainly occurred through the South Fork of the St. Lucie River; however, when flow increased through control structures along the C-23 and C-24 Canals, the North Fork was a larger than usual contributor of total freshwater inflow to the estuary. At one tidal site (Steele Point), the majority of flow was southward toward the St. Lucie Inlet; at a second tidal site (Indian River Bridge), the majority of flow was northward into the Indian River Lagoon. Large-volume stormwater discharge events greatly affected the St. Lucie River Estuary. Increased discharge typically was accompanied by salinity decreases that resulted in water becoming and remaining fresh throughout the estuary until the discharge events ended. Salinity in the estuary usually returned to prestorm levels within a few days after the events. Turbidity decreased and salinity began to increase almost immediately when the gates at the control structures closed. Salinity ranged from less than 1 to greater than 35 parts per thousand during the period of record (1998-2001), and typically varied by several parts per thousand during a tidal cycle. Suspended-solids concentrations were observed at one canal site (S-80) and two tidal sites (Speedy Point and Steele Point) during a discharge event in April and May 2000. Results suggest that most deposition of suspended-solids concentration occurs between S-80 and Speedy Point. The turbidity data collected also support this interpretation. The ratio of inorganic to organic suspended-solids concentration observed at S-80, Speedy Point, and Steele Point during the discharge event indicates that most flocculation of suspended-solids concentration occurs between Speedy Point and Steele Point.

Open-File Report↗
USGS2004

Stratton Sagebrush Hydrology Study Area: An annotated bibliography of research conducted 1968-1990

This annotated bibliography provides an overview of research projects conducted on the Stratton Sagebrush Hydrology Study Area (Stratton) since its designation as such in 1967. Sources include the Rocky Mountain Forest and Range Experiment Station records storage room, Laramie, Wyoming, the USGS and USFS online reference libraries, and scientific journal databases at the University of Wyoming and Colorado State University. This annotated bibliography summarizes publications from research conducted at Stratton during the prime of its tenure as a research lab from 1968 to 1990. In addition, an appendix is included that catalogues all data on file at the Rocky Mountain Forest and Range Experiment Station in Laramie, Wyoming. Each file folder was searched and its contents recorded here for the researcher seeking original data sets, charts, photographs and records.

Open-File Report↗
USGS2005

Historical development of the U.S. Geological Survey hydrologic monitoring and investigative programs at the Idaho National Engineering and Environmental Laboratory, Idaho, 1949 to 2001

This report is a summary of the historical development, from 1949 to 2001, of the U.S. Geological Survey's (USGS) hydrologic monitoring and investigative programs at the Idaho National Engineering and Environmental Laboratory. The report covers the USGS's water-level monitoring program, water-quality sampling program, geophysical program, geologic framework program, drilling program, modeling program, surface-water program, and unsaturated-zone program. The report provides physical information about the wells and information about the frequencies of sampling and measurement. Summaries of USGS published reports with U.S. Department of Energy (DOE) report numbers also are provided in an appendix. This report was prepared by the USGS in cooperation with the DOE.

Open-File Report↗
USGS2006

Hydrology, description of computer models, and evaluation of selected water-management alternatives in the San Bernardino area, California

The San Bernardino area of southern California has complex water-management issues. As an aid to local water managers, this report provides an integrated analysis of the surface-water and ground-water systems, documents ground-water flow and constrained optimization models, and provides seven examples using the models to better understand and manage water resources of the area. As an aid to investigators and water managers in other areas, this report provides an expanded description of constrained optimization techniques and how to use them to better understand the local hydrogeology and to evaluate inter-related water-management problems. In this report, the hydrology of the San Bernardino area, defined as the Bunker Hill and Lytle Creek basins, is described and quantified for calendar years 1945-98. The major components of the surface-water system are identified, and a routing diagram of flow through these components is provided. Annual surface-water inflow and outflow for the area are tabulated using gaged measurements and estimated values derived from linear-regression equations. Average inflow for the 54-year period (1945-98) was 146,452 acre-feet per year; average outflow was 67,931 acre-feet per year. The probability of exceedance for annual surface-water inflow is calculated using a Log Pearson Type III analysis. Cumulative surface-water inflow and outflow and ground-water-level measurements indicate that the relation between the surface-water system and the ground-water system changed in about 1951, in about 1979, and again in about 1992. Higher ground-water levels prior to 1951 and between 1979 and 1992 induced ground-water discharge to Warm Creek. This discharge was quantified using streamflow measurements and can be estimated for other time periods using ground-water levels from a monitoring well (1S/4W-3Q1) and a logarithmic-regression equation. Annual wastewater discharge from the area is tabulated for the major sewage and power-plant facilities. More...

Open-File Report↗
USGS2006

Geology, hydrology, and water quality of the glacial drift aquifer in the vicinity of the Nelson landfill near Yorkville, Illinois

The geologic and hydrologic characteristics of the sand-and-gravel deposits that compose the glacial drift aquifer in the vicinity of the Nelson Landfill site in Yorkville, Illinois indicate that the aquifer could be developed as a source of public water supply. The geology of these deposits within the Newark Bedrock Valley is complex, however, and a detailed investigation of their water bearing and transmitting properties will be required to successfully locate high-capacity wells. Volatile organic compounds, pesticides, and cyanide were not detected in ground water during this investigation. Metals and nitrogen compounds were not detected at concentrations above their Maximum Contaminant Level. Iron, manganese, and aluminum were detected at concentrations above their Secondary Maximum Con-taminant Level and various constituents were detected at concentrations above background levels downgradient of the landfill. Nitrate and ammonia, presumably derived from agricultural practices, also were detected in samples from locations hydraulically upgradient of the landfill. Oxidation-reduction conditions in the aquifer become more reducing with depth. This change is reflected by a change in the type of nitrogen compound detected and the concentration of dissolved oxygen and iron in the glacial drift aquifer. Concentrations of some of the major ions and metals may be affected by dissolution of carbonate minerals in the aquifer and perhaps road salts.

Open-File Report↗
USGS2006

Characterization of the hydrology, water chemistry, and aquatic communities of selected springs in the St. Johns River Water Management District, Florida, 2004

The hydrology, water chemistry, and aquatic communities of Silver Springs, De Leon Spring, Gemini Springs, and Green Spring in the St. Johns River Water Management District, Florida, were studied in 2004 to provide a better understanding of each spring and to compile data of potential use in future water-management decisions. Ground water that discharges from these and other north-central Florida springs originates from the Upper Floridan aquifer of the Floridan aquifer system, a karstic limestone aquifer that extends throughout most of the State's peninsula. This report summarizes data about flow, water chemistry, and aquatic communities, including benthic invertebrates, fishes, algae, and aquatic macrophytes collected by the U.S. Geological Survey, the St. Johns River Water Management District, and the Florida Department of Environmental Protection during 2004, as well as some previously collected data. Differences in water chemistry among these springs reflect local differences in water chemistry in the Upper Floridan aquifer. The three major springs sampled at the Silver Springs group (the Main Spring, Blue Grotto, and the Abyss) have similar proportions of cations and anions but vary in nitrate and dissolved oxygen concentrations. Water from Gemini Springs and Green Spring has higher proportions of sodium and chloride than the Silver Springs group. Water from De Leon Spring also has higher proportions of sodium and chloride than the Silver Springs group but lower proportions of calcium and bicarbonate. Nitrate concentrations have increased over the period of record at all of the springs except Green Spring. Compounds commonly found in wastewater were found in all the springs sampled. The most commonly detected compound was the insect repellant N,N'-diethyl-methyl-toluamide (DEET), which was found in all the springs sampled except De Leon Spring. The pesticide atrazine and its degradate 2-chloro-4-isopropylamino-6-amino-s-triazine (CIAT) were detected in water from the Silver Springs group and in both boils at Gemini Springs. No pesticides were detected in water samples from De Leon Spring and Green Spring. Evidence of denitrification was indicated by the presence of excess nitrogen gas in water samples from most of the springs. Aquatic communities varied among the springs. Large floating mats of cyanobacteria (blue-green algae), identified as Lyngbya wollei, were observed in De Leon Spring during all sampling events in 2004. At Gemini Springs, the dominant periphyton was Rhizoclonium sp. Of the three springs sampled for benthic invertebrates, De Leon Spring had the highest overall species richness and most disturbance intolerant species (Florida Index = 4). Green Spring had the lowest species richness of the springs sampled. Based on qualitative comparisons, overall macroinvertebrate species richness seemed to be negatively related to magnesium, potassium, sodium, and specific conductance. Invertebrate abundance was greatest when dissolved oxygen and nitrate were high but phosphorus and potassium concentrations were low. Dipteran abundance seemed to be positively associated with specific conductance and total organic carbon but negatively associated with nitrate-N. Amphipods were the numerically dominant group collected in most (six of nine) collections. Shifts in amphipod abundance of the two species collected (Gammarus sp. and Hyalella azteca) varied by season among the three springs, but there were no trends evident in the variation. Fish populations were relatively species-rich at the Silver Springs group, De Leon Spring, and Gemini Springs, but not at Green Spring. Nonindigenous fish species were observed at all springs except Green Spring.

Open-File Report↗
USGS2007

Marl prairie vegetation response to 20th century hydrologic change

We conducted geochronologic and pollen analyses from sediment cores collected in solution holes within marl prairies of Big Cypress National Preserve to reconstruct vegetation patterns of the last few centuries and evaluate the stability and longevity of marl prairies within the greater Everglades ecosystem. Based on radiocarbon dating and pollen biostratigraphy, these cores contain sediments deposited during the last ~300 years and provide evidence for plant community composition before and after 20th century water management practices altered flow patterns throughout the Everglades. Pollen evidence indicates that pre-20th century vegetation at the sites consisted of sawgrass marshes in a peat-accumulating environment; these assemblages indicate moderate hydroperiods and water depths, comparable to those in modern sawgrass marshes of Everglades National Park. During the 20th century, vegetation changed to grass-dominated marl prairies, and calcitic sediments were deposited, indicating shortening of hydroperiods and occurrence of extended dry periods at the site. These data suggest that the presence of marl prairies at these sites is a 20th century phenomenon, resulting from hydrologic changes associated with water management practices.

Florida↗
USGS2007

Chemical and hydrologic data from the Cement Creek and upper Animas River confluence and mixing zone, Silverton, Colorado, September 1997

Cement Creek, an acidic tributary, discharges into the circum-neutral Animas River (pH>7) in Silverton, Colorado located in the high-elevation San Juan Mountains. Mixing of Animas River water with acidic metal rich Cement Creek water raises water pH and produces metal precipitates. This report presents selected anion, cation, chloride, and sulfate data along with hydrologic data highlighting the mixing of these streams during the low-flow period in late summer 1997.

Colorado↗
USGS2008

Hydrologic data from the study of acidic contamination in the Miami Wash— Pinal Creek Area, Arizona, water years 1997–2004

Since 1984, hydrologic data have been collected as part of a U.S. Geological Survey study of the occurrence and movement of acidic contamination in the aquifer and streams of the Pinal Creek drainage basin near Globe, Arizona. Ground-water data from that study are presented for water years 1997 through 2004 and include location, construction information, site plans, water levels, chemical and physical field measurements, and selected chemical analyses of water samples for 31 project wells. Hydrographs of depth to ground water are also included. Surface-water data for four sites are also presented and include selected chemical analyses of water samples. Monthly precipitation data and long-term precipitation statistics are presented for two sites. Chemical analyses of samples collected from the stream and shallow ground water in the perennial reach of Pinal Creek are also included.

Arizona↗
USGS2010

Neosho madtom and other ictalurid populations in relation to hydrologic characteristics of an impounded Midwestern warmwater stream: Update

The Neosho madtom, Noturus placidus , is a small (less than 75 millimeters in total length) ictalurid that is native to the main stems of the Neosho and Cottonwood Rivers in Kansas and Oklahoma and the Spring River in Kansas and Missouri. The Neosho madtom was federally listed as threatened by the U.S. Fish and Wildlife Service in May 1990. The U.S. Fish and Wildlife Service has been monitoring Neosho madtoms since 1991, and questioned whether or not Neosho madtom densities were affected by other catfish species, reservoirs, and hydrologic characteristics. Using the first 8 years of U.S. Fish and Wildlife Service monitoring data, Wildhaber and others (2000) analyzed whether or not Neosho madtom densities were related to these environmental characteristics. The goal of this report is to update these results with data from 1999 to 2008. The trends of Neosho madtom densities in respect to John Redmond Reservoir and other catfish species remains consistent with the previous report. In both the Neosho and Spring Rivers, Neosho madtoms had a significant positive association with all catfish species. Of those species tested, only in the population of Neosho madtoms were significantly different in density above verses below the John Redmond Reservoir after accounting for the yearly variation. The average density of Neosho madtoms at the streamgage immediately below the reservoir had the second lowest density compared to the other streamgages. The positive associations with Neosho madtoms that remained consistent from the previous report included the 1-, 3-, and 7-day minima discharges and the annual minimum discharge from the previous water year (water year prior to when the fish were sampled) and the 1-, 3-, 7-, and 30-day minima discharges from the current water year (same water year fish were sampled).

Kansas, Missouri, Oklahoma↗
USGS2011

Summary of hydrologic testing of the Floridan aquifer system at Fort Stewart, Georgia

Two test wells were completed at Fort Stewart, GA, in January and February 2010 to investigate the potential of using the Lower Floridan aquifer as a source of water to satisfy anticipated increases in water use. One well was completed in the Lower Floridan aquifer at a depth of 1,255 feet below land surface; the other well was completed in the Upper Floridan aquifer at a depth of 560 feet below land surface. The U.S. Geological Survey conducted hydrologic testing at the well site including flowmeter surveys, slug tests within packer-isolated intervals of the Lower Floridan confining unit, and aquifer tests of the Upper and Lower Floridan aquifers. Flowmeter surveys at the study site indicate several permeable zones within the Floridan aquifer system. The Upper Floridan aquifer is composed of two water-bearing zones-the upper zone and the lower zone. The upper zone extends from 520 to 650 feet below land surface, contributes 96 percent of the total flow, and is more permeable than the lower zone, which extends from 650 to 705 feet below land surface and contributes the remaining 4 percent of the flow. The Lower Floridan aquifer consists of three zones at depths of 912-947, 1,090-1,139, and 1,211-1,250 feet below land surface that are inter-layered with three less-permeable zones. The Lower Floridan confining unit includes a permeable zone that extends from 793 to 822 feet below land surface. Horizontal hydraulic conductivity values of the Lower Floridan confining unit derived from slug tests within four packer-isolated intervals were from 2 to 20 feet per day, with a high value of 70 feet per day obtained for one of the intervals. Aquifer testing, using analytical techniques and model simulation, indicated the Upper Floridan aquifer had a transmissivity of about 100,000 feet squared per day, and the Lower Floridan aquifer had a transmissivity of 7,000 feet squared per day. Flowmeter surveys, slug tests within packer-isolated intervals, and parameter-estimation results indicate that the hydraulic properties of the Lower Floridan confining unit are similar to those of the Lower Floridan aquifer. Water-level data, for each aquifer test, were filtered for external influences such as barometric pressure, earth-tide effects, and long-term trends to enable detection of small water-level responses to aquifer-test pumping of less than 1 foot. During a 72-hour aquifer test of the Lower Floridan aquifer, a drawdown response of 0.3 to 0.4 foot was observed in two Upper Floridan aquifer wells, one of which was more than 1 mile away from the pumped well.

Georgia↗
USGS2012

Thermal and hydrological observations near Twelvemile Lake in discontinuous permafrost, Yukon Flats, interior Alaska, September 2010-August 2011

A series of ground-based observations were made between September 2010 and August 2011 near Twelvemile Lake, 19 kilometers southwest of Fort Yukon, Alaska, for use in ongoing hydrological analyses of watersheds in this region of discontinuous permafrost. Measurements include depth to ground ice, depth to water table, soil texture, soil moisture, soil temperature, and water pressure above the permafrost table. In the drained basin of subsiding Twelvemile Lake, we generally find an absence of newly formed permafrost and an undetectable slope of the water table; however, a sloping water table was observed in the low-lying channels extending into and away from the lake watershed. Datasets for these observations are summarized in this report and can be accessed by clicking on the links in each section or from the Downloads folder of the report Web page.

Alaska↗
USGS2012

Hydrologic data for an investigation of the Smith River Watershed through water year 2010

Hydrologic data collected through water year 2010 and compiled as part of a U.S. Geological Survey study of the water resources of the Smith River watershed in west-central Montana are presented in this report. Tabulated data presented in this report were collected at 173 wells and 65 surface-water sites. Figures include location maps of data-collection sites and hydrographs of streamflow. Digital data files used to construct the figures, hydrographs, and data tables are included in the report. Data collected by the USGS are also stored in the USGS National Water Information System database and are available through the USGS National Water Information System Water Data for Montana Web page at http://waterdata.usgs.gov/mt/nwis/ .

Montana↗
USGS2012

Independent technical review and analysis of hydraulic modeling and hydrology under low-flow conditions of the Des Plaines River near Riverside, Illinois

The U.S. Geological Survey (USGS) has operated a streamgage and published daily flows for the Des Plaines River at Riverside since Oct. 1, 1943. A HEC-RAS model has been developed to estimate the effect of the removal of Hofmann Dam near the gage on low-flow elevations in the reach approximately 3 miles upstream from the dam. The Village of Riverside, the Illinois Department of Natural Resources-Office of Water Resources (IDNR-OWR), and the U. S. Army Corps of Engineers-Chicago District (USACE-Chicago) are interested in verifying the performance of the HEC-RAS model for specific low-flow conditions, and obtaining an estimate of selected daily flow quantiles and other low-flow statistics for a selected period of record that best represents current hydrologic conditions. Because the USGS publishes streamflow records for the Des Plaines River system and provides unbiased analyses of flows and stream hydraulic characteristics, the USGS served as an Independent Technical Reviewer (ITR) for this study.

Illinois↗
USGS2012

Hydrological information products for the Off-Project Water Program of the Klamath Basin Restoration Agreement

The Klamath Basin Restoration Agreement (KBRA) was developed by a diverse group of stakeholders, Federal and State resource management agencies, Tribal representatives, and interest groups to provide a comprehensive solution to ecological and water-supply issues in the Klamath Basin. The Off-Project Water Program (OPWP), one component of the KBRA, has as one of its purposes to permanently provide an additional 30,000 acre-feet of water per year on an average annual basis to Upper Klamath Lake through "voluntary retirement of water rights or water uses or other means as agreed to by the Klamath Tribes, to improve fisheries habitat and also provide for stability of irrigation water deliveries." The geographic area where the water rights could be retired encompasses approximately 1,900 square miles. The OPWP area is defined as including the Sprague River drainage, the Sycan River drainage downstream of Sycan Marsh, the Wood River drainage, and the Williamson River drainage from Kirk Reef at the southern end of Klamath Marsh downstream to the confluence with the Sprague River. Extensive, broad, flat, poorly drained uplands, valleys, and wetlands characterize much of the study area. Irrigation is almost entirely used for pasture. To assist parties involved with decisionmaking and implementation of the OPWP, the U.S. Geological Survey (USGS), in cooperation with the Klamath Tribes and other stakeholders, created five hydrological information products. These products include GIS digital maps and datasets containing spatial information on evapotranspiration, subirrigation indicators, water rights, subbasin streamflow statistics, and return-flow indicators. The evapotranspiration (ET) datasets were created under contract for this study by Evapotranspiration, Plus, LLC, of Twin Falls, Idaho. A high-resolution remote sensing technique known as Mapping Evapotranspiration at High Resolution and Internalized Calibration (METRIC) was used to create estimates of the spatial distribution of ET. The METRIC technique uses thermal infrared Landsat imagery to quantify actual evapotranspiration at a 30-meter resolution that can be related to individual irrigated fields. Because evaporation uses heat energy, ground surfaces with large ET rates are left cooler as a result of ET than ground surfaces that have less ET. As a consequence, irrigated fields appear in the Landsat images as cooler than nonirrigated fields. Products produced from this study include total seasonal and total monthly (April-October) actual evapotranspiration maps for 2004 (a dry year) and 2006 (a wet year). Maps showing indicators of natural subirrigation were also provided by this study. "Subirrigation" as used here is the evapotranspiration of shallow groundwater by plants with roots that penetrate to or near the water table. Subirrigation often occurs at locations where the water table is at or above the plant rooting depth. Natural consumptive use by plants diminishes the benefit of retiring water rights in subirrigated areas. Some agricultural production may be possible, however, on subirrigated lands for which water rights are retired. Because of the difficulty in precisely mapping and quantifying subirrigation, this study presents several sources of spatially mapped data that can be used as indicators of higher subirrigation probability. These include the floodplain boundaries defined by stream geomorphology, water-table depth defined in Natural Resources Conservation Service (NRCS) soil surveys, and soil rooting depth defined in NRCS soil surveys. The two water-rights mapping products created in the study were "points of diversion" (POD) and "place of use" (POU) for surface-water irrigation rights. To create these maps, all surface-water rights data, decrees, certificates, permits, and unadjudicated claims within the entire 1,900 square mile study area were aggregated into a common GIS geodatabase. Surface-water irrigation rights within a 5-mile buffer of the study area were then selected and identified. The POU area was then totaled by water right for primary and supplemental water rights. The maximum annual volume (acre-feet) allowed under each water right also was calculated using the POU area and duty (allowable annual irrigation application in feet). In cases where a water right has more than one designated POD, the total volume for the water right was equally distributed to each POD listed for the water right. Because of this, mapped distribution of diversion rates for some rights may differ from actual practice. Water-right information in the map products was from digital datasets obtained from the Oregon Water Resources Department and was, at the time acquired, the best available compilation of water-right information available. Because the completeness and accuracy of the water-right data could not be verified, users are encouraged to check directly with the Oregon Water Resources Department where specific information on individual rights or locations is essential. A dataset containing streamflow statistics for 72 subbasins in the study area was created for the study area. The statistics include annual flow durations (5-, 10-, 25-, 50-, and 95-percent exceedances) and 7-day, 10-year (7Q10) and 7-day, 2-year (7Q2) low flows, and were computed using regional regression equations based on measured streamflow records in the region. Daily streamflow records used were adjusted as needed for crop consumptive use; therefore the statistics represent streamflow under more natural conditions as though irrigation diversions did not exist. Statistics are provided for flow rates resulting from streamflow originating from within the entire drainage area upstream of the subbasin pour point (referring to the outlet of the contributing drainage basin). The statistics were computed for the purpose of providing decision makers with the ability to estimate streamflow that would be expected after water conservation techniques have been implemented or a water right has been retired. A final product from the study are datasets of indicators of the potential for subsurface return flow of irrigation water from agricultural areas to nearby streams. The datasets contain information on factors such as proximity to surface-water features, geomorphic floodplain characteristics, and depth to water. The digital data, metadata, and example illustrations for the datasets described in this report are available on-line from the USGS Water Resources National Spatial Data Infrastructure (NSDI) Node Website http://water.usgs.gov/lookup/getgislist or from the U.S. Government website DATA.gov at http://www.data.gov with links provided in a Microsoft® Excel® workbook in appendix A.

California;Oregon↗
USGS2013

Hydrologic conditions in New Hampshire and Vermont, water year 2011

Record-high hydrologic conditions in New Hampshire and Vermont occurred during water year 2011, according to data from 125 streamgages and lake gaging stations, 27 creststage gages, and 41 groundwater wells. Annual runoff for the 2011 water year was the sixth highest on record for New Hampshire and the highest on record for Vermont on the basis of a 111-year reference period (water years 1901–2011). Groundwater levels for the 2011 water year were generally normal in New Hampshire and normal to above normal in Vermont. Record flooding occurred in April, May, and August of water year 2011. Peak-of-record streamflows were recorded at 38 streamgages, 25 of which had more than 10 years of record. Flooding in April 2011 was widespread in parts of northern New Hampshire and Vermont; peak-of-record streamflows were recorded at nine streamgages. Flash flooding in May 2011 was isolated to central and northeastern Vermont; peakof- record streamflows were recorded at five streamgages. Devastating flooding in August 2011 occurred throughout most of Vermont and in parts of New Hampshire as a result of the heavy rains associated with Tropical Storm Irene. Peak-ofrecord streamflows were recorded at 24 streamgages.

New Hampshire;Vermont↗
USGS2014

Hydrologic monitoring of a landslide-prone hillslope in the Elliott State Forest, Southern Coast Range, Oregon, 2009-2012

The Oregon Coast Range is dissected by numerous unchanneled headwater basins, which can generate shallow landslides and debris flows during heavy or prolonged rainfall. An automated monitoring system was installed in an unchanneled headwater basin to measure rainfall, volumetric water content, groundwater temperature, and pore pressures at 15-minute intervals. The purpose of this report is to describe and present the methods used for the monitoring as well as the preliminary data collected during the period from 2009 to 2012. Observations show a pronounced seasonal variation in volumetric water content and pore pressures. Increases in pore pressures and volumetric water content from dry-season values begin with the onset of the rainy season in the fall (typically early to mid October). High water contents and pore pressures tend to persist throughout the rainy season, which typically ends in May. Heavy or prolonged rainfall during the wet season that falls on already moist soils often generates positive pore pressures that are observed in the deeper instruments. These data provide a record of the basin’s hydrologic response to rainfall and provide a foundation for understanding the conditions that lead to landslide and debris-flow occurrence.

Oregon↗