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The diversion of freshwater from the Mississippi River is intended to mitigate saltwater intrusion from the Gulf of Mexico and to lessen the concomitant loss of wetland areas. Though effective, freshwater diversion can affect wildlife and habitat; therefore, prediversion and postdiversion data collections are necessary to identify effects. The Davis Pond freshwater diversion area is located between the Mississippi River and Bayou Lafourche and extends to Barataria Bay Basin, Louisiana. Results and interpretations from the prediversion biomonitoring done in 2001 - which included data on fish, eagles, and bivalves - are presented in the U.S. Geological Survey (USGS) Scientific Investigations Report 2008-5067, "Davis...
A generalized least squares (GLS) technique was used with at-site n-day low-flow time series and frequencies, from SWToolbox (Kiang and others, 2018), and 14 basin characteristics (basin perimeter, drainage area, maximum basin elevation, mean total annual reference evapotranspiration, groundwater head, length of longest flow path, minimum basin elevation, runoff-curve number, relief, ruggedness, slope ratio, percentage of hydrologic soil type B, available water capacity, and total length of streams in a basin) for 28 selected streamflow gaging stations in Puerto Rico to calculate regional n-day low-flow frequency regression equations for ungaged stream locations. The GLS approach assigns weights based on uncertainty...
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These data identify the time (0-1 min, 1-2 min,or 2-3 min) and distance (≤50 meters, >50 meters) category when birds were first detected during 3-minutes point counts at stop locations associated with North American Breeding Bird Survey routes or route equivalents that were surveyed on dates between 2009 and 2016 and provide point location coordinates of stop locations along North American Breeding Bird Survey routes or route equivalents within (or within 60 miles) the Gulf Coastal Plains & Ozarks Landscape Conservation Cooperative boundary.
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Regional regression equations were calculated in Puerto Rico with generalized least squares techniques to estimate flood frequency statistics at ungaged locations using drainage area as the only explanatory variable. The island was divided into 2 regions to minimize residuals. The region division that resulted in lower and more balanced residuals runs primarily north-south near the center of the island, mostly along an 8-digit hydrologic unit code (HUC8) boundary. The division line runs through a HUC8 polygon on the southern end of the island, but care was taken to include entire watersheds and consideration was given where hydrologic and physiographic properties differed. This data release includes geographic information...
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This data product consists of a database of population change and abundance estimates for North American birds, estimated from North American Breeding Bird Survey (BBS) data. Data are presented for 548 species of birds in 4 spreadsheets containing trend estimates and annual indices for 2 time periods. Estimates are derived for each species using the 1 of 4 alternative models, and a cross-validation model selection procedure was used to select the best model for each species.
This community serves to document data and analysis collected by researchers within the Upper Midwest Water Science Center whose mission is to collect high-quality hydrologic data and conduct unbiased, scientifically sound studies of water resources within the Great Lakes and Upper Mississippi Basins. We strive to meet the changing needs of those who use our information—from the distribution, availability, and quality of our water resources to topic-oriented research that addresses current hydrological issues.
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This part of the Data Release contains the raster representation of the water-level altitude and water-level change maps developed every 5 years from 1980-2015 for the upper Rio Grande Focus Area Study. The input point data used to generate the water-level altitude maps can be found in the "Groundwater level measurement data used to develop water-level altitude maps in the upper Rio Grande Alluvial Basins" child item of this data release. These digital data accompany Houston, N.A., Thomas, J.V., Foster, L.K., Pedraza, D.E., and Welborn, T.L., 2020, Hydrogeologic framework, groundwater-level altitudes, groundwater-level changes, and groundwater-storage changes in selected alluvial basins of the upper Rio Grande...
Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: Abiquiu Reservoir, Ahumada, Alamosa, Alamosa County, Alamosa Creek, All tags...
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The U.S. Geological Survey's (USGS) SPAtially Referenced Regression On Watershed attributes (SPARROW) model was used to aid in the interpretation of monitoring data and simulate streamflow and water-quality conditions in streams across the Pacific Region of the Unites States. SPARROW is a hybrid empirical/process-based mass balance model that can be used to estimate the major sources and environmental factors that affect the long-term supply, transport, and fate of contaminants in streams. The spatially explicit model structure is defined by a river reach network coupled with contributing catchments. The model is calibrated by statistically relating watershed sources and transport-related properties to monitoring-based...
This file (wymt_ffa_2018D_WATSTORE.txt) contains peak flow data for peak-flow frequency analyses for selected streamgages in and near the Milk River Basin, Montana, based on data through water year 2018. The file is in a text format called WATSTORE (National Water Data Storage and Retrieval System) available from NWISWeb (http://nwis.waterdata.usgs.gov/usa/nwis/peak).
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This data release contains daily time series estimates of natural streamflow at 5,439 GAGES-II non-reference streamgages in 19 study regions across the conterminous United States from October 1, 1980 through September 30, 2017, using five statistical techniques: nearest-neighbor drainage area ratio (NNDAR), map-correlation drainage area ratio (MCDAR), nearest-neighbor nonlinear spatial interpolation using flow duration curves (NNQPPQ), map-correlation nonlinear spatial interpolation using flow duration curves (MCQPPQ), and ordinary kriging of the logarithms of discharge per unit area (OKDAR). NNDAR, MCDAR, NNQPPQ, and MCQPPQ estimates were computed following methods described in Farmer and others (2014), with...
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This dataset contains all of the supporting materials to accompany Helsel, D.R., Hirsch, R.M., Ryberg, K.R., Archfield, S.A., and Gilroy, E.J., 2020, Statistical methods in water resources: U.S. Geological Survey Techniques and Methods, book 4, chapter A3, 454 p., https://doi.org/10.3133/tm4a3. [Supersedes USGS Techniques of Water-Resources Investigations, book 4, chapter A3, version 1.1.]. Supplemental material (SM) for each chapter are available to re-create all examples and figures, and to solve the exercises at the end of each chapter, with relevant datasets provided in an electronic format readable by R. The SM provide (1) datasets as .Rdata files for immediate input into R, (2) datasets as .csv files for input...
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The Massachusetts Office of Coastal Zone Management launched the Shoreline Change Project in 1989 to identify erosion-prone areas of the coast. The shoreline position and change rate are used to inform management decisions regarding the erosion of coastal resources. In 2001, a 1994 shoreline was added to calculate both long- and short-term shoreline change rates at 40-meter intervals along ocean-facing sections of the Massachusetts coast. In 2013 two oceanfront shorelines for Massachusetts were added using 2008-2009 color aerial orthoimagery and 2007 topographic lidar datasets obtained from NOAA's Ocean Service, Coastal Services Center. This 2018 update includes two new mean high water (MHW) shorelines for the Massachusetts...
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The diversion of freshwater from the Mississippi River is intended to mitigate saltwater intrusion from the Gulf of Mexico and to lessen the concomitant loss of wetland areas. Though effective, freshwater diversion can affect wildlife and habitat; therefore, prediversion and postdiversion data collections are necessary to identify effects. The Davis Pond freshwater diversion area is located between the Mississippi River and Bayou Lafourche and extends to Barataria Bay Basin, Louisiana. Results and interpretations from the prediversion biomonitoring done in 2001 - which included data on fish, eagles, and bivalves - are presented in the U.S. Geological Survey (USGS) Scientific Investigations Report 2008-5067, "Davis...
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This report documents the spatial and temporal variability of nutrients and related water quality parameters at high spatial resolution in the North Delta in the Sacramento-San Joaquin River Delta of California, USA. The data set includes nitrate, ammonium, phosphate, dissolved organic carbon, temperature, conductivity, dissolved oxygen, turbidity, and chlorophyll. Data-collection were conducted over one day in July 2017 when continuous monitoring stations detected elevated chlorophyll concentration and decreasing nitrate concentrations.
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The data release contains data for the spatial and temporal variability of nutrients and related water quality parameters at high spatial resolution in the North Delta in the Sacramento-San Joaquin River Delta of California, USA. The data set includes nitrate, ammonium, phosphate, dissolved organic carbon, temperature, conductivity, dissolved oxygen, turbidity, and chlorophyll. Data-collection cruises were conducted over two days in March 2017 during a high flow event when Sacramento Valley flood waters inundate the Yolo Bypass.
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This release contains borehole geophysical electrical log data (elogs), total dissolved solids sample data (TDS), and geostatistical program files used to estimate the salinity distribution in groundwater above and in the vicinity of the Montebello Oil Field, located near Los Angeles, California, USA. Original data are drawn from a variety of publicly available sources and are combined here for use in geostatistical simulation and estimation. The extent of the estimation area is a 3-mile buffer zone surrounding the Montebello Oil Field administrative boundary, and the subsurface aquifer region lying above locally mapped oil-bearing units. The data compilation and analysis were done as part of the California State...
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This dataset contains taxonomy, density (cells/mL), and biovolume (μm3/mL) data for phytoplankton sampled across the Sacramento San Joaquin River Delta and San Francisco Bay (Bay-Delta) beginning in 2016. Whole water phytoplankton samples were collected intermittently during special projects and during routine visits to service continuous monitoring stations. Samples were preserved with Lugol’s iodine solution (2-5 %) immediately after collection and stored in a cool, dark environment until analysis. Preserved whole water samples are sent to BSA Environmental Services (BSA) in Beachwood, Ohio for microscopic identification and enumeration. A Leica DMLB compound microscope is used for enumerating filtered phytoplankton...
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This data release contains the standard statistical suite (version 1.0) daily streamflow performance benchmark results for the National Water Model Retrospective (v2.1) at streamflow benchmark locations defined by Foks and others (2022). Modeled hourly timesteps were converted to mean daily timesteps. Model error was determined by evaluating predicted daily mean streamflow versus observed daily mean streamflow using various statistics; the Nash-Sutcliffe efficiency (NSE), the Kling-Gupta efficiency (KGE), the logNSE, the Pearson correlation coefficient, the Spearman correlation coefficient, the ratio of the standard deviation, the percent bias, the percent bias in flow duration curve midsegment slope, the percent...