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Seventeen streamflow-gaging stations, operated by the U.S. Geological Survey and distributed across the Ouachita Mountains of Arkansas and Oklahoma were selected for analysis. Bed material sampling was conducted to obtain information on the particle-size distributions of the streambed materials and to determine the shapes of the individual particles comprising the streambeds. Information on stream-bed particle-size distribution was used to compute the potential rate of bed-load transport and is a parameter used in the Rosgen (Rosgen, 1996) stream reach classification system. Streambed-material particle sizes were measured using two methods. The first method was Wolman pebble counts conducted across the riffles...
This data set includes WRTDS nutrient flux trend results and the values of daily streamflow trend results displayed in the Quantile-Kendall plots. For 1995-2015 nutrient trends, the method of generalized flow normalization (FNG) was used which explicitly addresses non-stationary streamflow conditions. For 2005-2015 nutrient trends, the WRTDS trend analyses used the method of stationary flow normalization (FNS) because streamflow nonstationarity is difficult to assess over this shorter duration time frame. The 1995-2015 annual nutrient trends were determined for all five nutrient parameters (TP, SRP, TN, NO23, TKN), and monthly trends were evaluated only for SRP. The 2005-2015 annual nutrient trends were determined...
DC Resitivity Methodology Direct current (DC) resistivity transects were surveyed using an IRIS Syscal Pro Switch 96 instrument (IRIS Instruments, Inc., Orléans, France). Steel electrodes were hammered into the ground at a fixed distance along the profile. These were connected to the instrument using copper wires and junction boxes. The number of electrodes on each profile and their spacing is shown below: Line 1: 180 electrodes, 5 meter spacing Line 2: 48 electrodes, 2 meter spacing Line 3: 48 electrodes, 2 meter spacing Line 4: 24 electrodes, 2 meter spacing Line 5: 36 electrodes, 2 meter spacing On Line 1, the roll-along method was used to extend the line to its full extent. In this method, 48 electrodes...
Categories: Data
FDEM Methodology For this project frequency domain electromagnetic (FDEM) data were collected with a GEM-2, a broadband, multifrequency, fixed-coil electromagnetic induction unit (Geophex, 2015). Both in-phase and quadrature data were collected on 15 channels from a frequency of 810 Hz to 66,090 Hz. This system was carried along profiles that followed the axis of the dam and along tie lines that were perpendicular to the axis of the dam. Each data point was located using a backpack mounted GPS. To correct the drift of the instrument, a base station was established on the east side of the dam. Each survey started and ended with an occupation of the base station. These occupations occur as even line numbers...
Categories: Data
Reelfoot Lake, in northwestern Tennessee and southwestern Kentucky, is home to a Federal wildlife refuge, a State wildlife-management area, and to a tourism industry that is based on hunting, fishing, birding, and the area’s unique cultural history. In 2012, the U.S. Geological Survey, in cooperation with the Tennessee Wildlife Resources Agency, began a series of hydrologic investigations to support the U.S. Fish and Wildlife Service in managing lake level. The objective was to develop operational models that preserved the historic patterns of variability that had characterized the lake for the past 60 years while meeting seasonal water-level targets (Heal and others, 2022). Preliminary models for gate operations...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Fulton County,
Lake County, Tennessee,
Obion County,
Reelfoot Lake, Tennessee,
Tennessee,
Nutrient and phytoplankton data indicate poor environmental health in four oxbow lakes in central Louisiana suggesting that long-term agriculture practices and increases in shoreline development have accelerated eutrophication. Surface-water quality and phytoplankton indicators of eutrophication were examined at Lake Bruin, Lake St. John, Lake St. Joseph, and False River Lake along an eutrophication gradient. These oxbow lakes are cut-off meanders of the Mississippi River that do not receive overbank flow from the river due to the levee system built in the early twentieth century. Oxbows have formed at various times in the last few hundred years as the Mississippi River carves a more efficient hydrologic route to...
Human alteration of waterways has impacted the minimum and maximum streamflow in more than 86% of monitored streams nationally and may be the primary cause for ecological impairment in river and stream ecosystems. Restoration of freshwater inflows can positively affect shellfish, fisheries, habitat, and water quality in streams, rivers, and estuaries. Increasingly, state and local decision makers and Federal agencies are turning their attention to the restoration of flows as part of a holistic approach to restoring water quality and habitat and protecting and replenishing living coastal and marine resources and the livelihoods that depend on them. In 2017, the U.S. Geological Survey (USGS) Lower Mississippi-Gulf...
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Alabama,
Florida,
Gulf Coast,
Gulf Coast,
Gulf of Mexico,
Note: this data release has been superseded by version 2.0, available here: https://doi.org/10.5066/P9G2MFRX. Salinity and variability of salinity in shallow waters shape living resources and habitat within Gulf of Mexico estuaries. The salinity gradient is widely recognized as foundational in maintaining biological diversity and productivity of estuaries. A clear understanding of the factors controlling salinity and variability of salinity in estuarine surface waters is essential for proper stewardship and for sustaining ecological structure and function. Salinity data are collected by numerous Federal, State, and local agencies and universities as part of routine data collection programs. We used online databases...
A bathymetric survey of Blue Mountain Lake, Arkansas, was conducted in May 2017 by the Lower Mississippi-Gulf Water Science Center of the U.S. Geological Survey (USGS) using methodologies for sonar surveys similar to those described by Wilson and Richards (2006). Point data from the bathymetric survey were merged with point data from an aerial LiDAR survey conducted in December 2010 for the U.S. Army Corps of Engineers (USACE), Little Rock District. From the combined point data, a terrain dataset (a type of triangulated irregular network, or TIN model) was created in Esri ArcGIS for the lakebed within the extent of pool elevation 420 feet above the North American Vertical Datum of 1988 (NAVD88). Products included...
Nutrient and phytoplankton data indicate poor environmental health in four oxbow lakes in central Louisiana suggesting that long-term agriculture practices and increases in shoreline development have accelerated eutrophication. Surface-water quality and phytoplankton indicators of eutrophication were examined at Lake Bruin, Lake St. John, Lake St. Joseph, and False River Lake along an eutrophication gradient. These oxbow lakes are cut-off meanders of the Mississippi River that do not receive overbank flow from the river due to the levee system built in the early twentieth century. Oxbows have formed at various times in the last few hundred years as the Mississippi River carves a more efficient hydrologic route to...
This data release presents tabular data and water-level drawdown model files for 32 Mississippi River Valley alluvial aquifer monitoring wells and 4 Memphis aquifer observation wells from an aquifer test conducted in October 2017 at the Tennessee Valley Authority Allen power plants in Memphis, Shelby County, Tennessee. The dataset contains the water-level model files used to estimate drawdown in the monitoring and observation wells during the aquifer test, created using the SeriesSEE Excel add-in program (Halford and others, 2012). The SeriesSEE Excel add-in also is included so that water-level models can be reactivated. Reference Cited: Halford, K.J., Garcia, C.A., Fenlon, J.M., and Mirus, B.B., 2012, Advanced...
In 2015-2016, physicochemical properties and chemical characteristics of stream water, bed sediment, groundwater, and soil were determined in watersheds located outside of, but in proximity to, the Peason Ridge Training Area and Main Post at the Joint Readiness Training Center and Fort Polk boundaries to document background trace element concentrations. Water samples were analyzed for physicochemical properties, major inorganic ions, selected trace elements, and dissolved organic carbon. Selected trace elements included antimony, arsenic, cadmium, copper, iron, lead, manganese, mercury, and zinc. Stream bed-sediment and soil samples were analyzed for major inorganic ions, selected trace elements, and grain size...
In 2015-2016, physicochemical properties and chemical characteristics of stream water, bed sediment, groundwater, and soil were determined in watersheds located outside of, but in proximity to, the Peason Ridge Training Area and Main Post at the Joint Readiness Training Center and Fort Polk boundaries to document background trace element concentrations. Water samples were analyzed for physicochemical properties, major inorganic ions, selected trace elements, and dissolved organic carbon. Selected trace elements included antimony, arsenic, cadmium, copper, iron, lead, manganese, mercury, and zinc. Stream bed-sediment and soil samples were analyzed for major inorganic ions, selected trace elements, and grain size...
GNSS Method A benchmark monument was set at each end of the earthen dam in accordance with (U.S. Army Corps of Engineers, 2002). A level II survey (Rydlund & Densmore 2012) was conducted on each monument to establish control. Two 4-hour observations were conducted with a staggered approach for each monument, with one 4-hour session in the morning of the first day and one 4-hour session in the afternoon of the second day. Once elevational control was established, a Real Time Kinematic (RTK) system was set up with base on the monument that had the best observations. Using this system, a point cloud survey was conducted along the top and face of the dam using both a monopod and an All-Terrain Vehicle. A Global...
Categories: Data
FDEM Processing The frequency domain electromagnetic (FDEM) data were downloaded from the GEM-2 instrument and aggregated into a single data file. The data were manually despiked and smoothed to remove negative values and the effects of metallic objects. A drift correction was applied by finding the average in-phase and average quadrature values for each frequency transmitted each time the base station was occupied. This average value was then used to calculate a linear trend of the data in time and the linear trend was subtracted from the data set. After the data were drift corrected, the data was leveled by calculating the arithmetic mean of the survey data subtracting that value from the dataset to level...
Categories: Data
Two methods of calculating hydrologic alteration were applied to modeled daily streamflow data for 9,201 12-digit hydrologic unit code (HUC12) pour points draining to the Gulf of Mexico (Robinson and others, 2020). The first method is a new modified method of calculating ecosurplus and ecodeficit called hydro change. For this project, ecosurplus and ecodeficit have been combined to assess overall hydrologic regime change. The second method is the confidence interval hypothesis test (Kroll and others, 2015). The first method is a means of quantifying hydrologic alteration while the second is a hypothesis test to simply determine if statistically significant alteration has occurred. Both methods are employed to determine...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Alabama,
Florida,
Gulf Coast,
Louisiana,
Mississippi,
A simple water budget includes precipitation, streamflow, change in storage, evapotranspiration, and residuals: P=Q + ET + ΔS + e. It is essential to include the managed component (i.e., the “human” component) to close the water budget and reduce the magnitude of the residuals from “natural” water budgets. Some of the largest components of managed water withdraws are public supply, irrigation, and thermoelectric. The modified water budget is: P=Q + ET + ΔS + (PS + Irr + TE) + e, where PS is public supply, Irr is irrigation, and TE is thermoelectric water use. This data release contains both the natural and managed components of the water budget for a region within the Apalachicola-Chattahoochee-Flint (ACF) River...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Apalachicola River,
Chattahoochee River,
Flint River,
Georgia,
Gulf Coast,
The dataset is a digital elevation model (DEM), in GeoTiff format, of the bathymetry of Dierks Lake, Howard and Sevier Counties, Arkansas. The extent of the DEM represents the area encompassing the extent of the aerial Light Detection And Ranging (LiDAR) data used in the project. Horizontal and vertical units are expressed in meters. The DEM was derived from an LAS dataset (an industry-standard binary format for storing aerial LiDAR data) created from point datasets stored in “Dierks2018_gdb”. The point datasets include aerial LiDAR data from a survey conducted in 2016 by the National Resources Conservation Service (U.S. Geological Survey, 2017), point data from digitized historical topographic maps, and bathymetric...
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: ADCP,
AR,
ASCII,
Acoustic,
Arkansas,
Nonstationary streamflow due to environmental and human-induced causes can affect water quality over time, yet these effects are poorly accounted for in water-quality trend models. This data release provides instream water-quality trends and estimates of two components of change, for sites across the Nation previously presented in Oelsner et al. (2017). We used previously calibrated Weighted Regressions on Time, Discharge, and Season (WRTDS) models published in De Cicco et al. (2017) to estimate instream water-quality trends and associated uncertainties with the generalized flow normalization procedure available in EGRET version 3.0 (Hirsch et al., 2018a) and EGRETci version 2.0 (Hirsch et al., 2018b). The procedure...
Categories: Data;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Contiguous United States and Puerto Rico,
USGS Science Data Catalog (SDC),
United States,
biota,
carbon,
FDEM Methodology For this project frequency domain electromagnetic (FDEM) data were collected with a GEM-2, a broadband, multifrequency, fixed-coil electromagnetic induction unit (Geophex, 2015). Both in-phase and quadrature data were collected on 15 channels from a frequency of 810 Hz to 66,090 Hz. This system was carried along profiles that followed the axis of the dam and along tie lines that were perpendicular to the axis of the dam. Each data point was located using a backpack mounted GPS. To correct the drift of the instrument, a base station was established on the east side of the dam. Each survey started and ended with an occupation of the base station. These occupations occur as even line numbers...
Categories: Data
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