Data

It is convenient to measure or estimate variation in samples or distributions in units of standard deviations. There are alternative methods of estimation of standard deviation aside from the conventional and well-known definition. Estimation of standard deviation for very small samples (as small as two), whereas not always ideal, might be useful in certain practical circumstances. A...

Statistical predictions that are based on multiple machine learning (MML) methods (from including differing training regimes) produce differing predictions. When the predictions are combined to a final estimate, then there are residuals of the predictions spread around the final estimate. It is common to assume normality or near-normality of the residuals (errors), but the assumption of...

Groundwater from the Mississippi River Valley alluvial aquifer (MRVA), coincident with the Mississippi Alluvial Plain (MAP), is a vital resource for agriculture and drinking-water supplies in the central United States. Water availability can be limited in some areas of the aquifer by high concentrations of salinity, measured as specific conductance. Boosted regression trees (BRT), a type...

Data in this release were collected and computed to evaluate the occurrence of pesticides in shallow groundwater in the state of Alabama. Additionally, these data support interpretation in Gill (2023) for a cooperative project between the U.S. Geological Survey and the Alabama Department of Agriculture and Industries. During 2009-2020, samples were collected from twenty-four wells...

The U.S. Geological Survey (USGS) works closely with the Mississippi Department of Transportation (MDOT) to provide information to be used by the MDOT for design of highway-drainage structures. MDOT spends millions of dollars annually for highway construction. Streamflow records, hydrologic analyses of basins, and hydraulic analyses of flooding potential at proposed highway crossings...

These datasets provide the locations of and groundwater-level altitudes from 273 wells that were used to construct a 2015 potentiometric contour surface of the Sparta-Memphis aquifer. Measurements were made from January through June 2015 and represent synoptic conditions. All wells were cased completely in and screened in the Sparta-Memphis aquifer. Groundwater-level data are also...

The RESTORE/covESTUSAL software repository contains R language source code useful for the construction of input tables of daily salinity and specific conductance (response variables) from multi-agency monitoring stations and potential predictor variables (covariates) intended for reuse in statistical model construction in coastal regions of the Gulf of Mexico, United States. The source...

Fern Cave in Jackson County, Alabama is the longest and deepest cave in Alabama with over 15 miles of cave passages and 536 feet of depth. The cave is cooperatively managed by the U.S. Fish and Wildlife Service and the Southeastern Cave Conservancy. At least three different streams flow through the cave including the Surprise, Lower North, and Bottom Cave streams. Two of these streams...

Dye tracing investigations were conducted in Cades Cove and Tuckaleechee Cove, two carbonate fensters in the western Great Smoky Mountains. These investigations were conducted as part of a two-year study examining the karst hydrology in the carbonate fensters. Main objectives of the dye tracing investigations were to determine resurgences for cave systems, delineate recharge areas for...

During the spring and summer of 2020, the U.S. Geological Survey, Lower Mississippi – Gulf Water Science Center, conducted single well slug tests on selected wells within the Mississippi Alluvial Plain in Arkansas and Mississippi to estimate hydraulic conductivity (K) and transmissivity (T) values for the aquifers in which the wells are screened. A total of 324 tests were conducted on 48...

This data release contains input and output data from hydrologic simulations of streamflow conditions in the Red River Basin (RRB) using the Precipitation-Runoff Modeling System (PRMS). The RRB PRMS model predicts components of the water balance at 3065 hydrologic response units (HRU) and streamflow for 1614 stream segments within the model domain for the simulation period 1981 to 2016...

This USGS data release includes a shapefile of outlet point locations for 12-digit hydrologic units (HU12s) from the Watershed Boundary Dataset (WBD), dated August 13, 2020 (U.S. Geological Survey and others, 2020), draining to the Gulf of Mexico in the south-central and southeastern United States. The outlet locations were derived by combining the WBD boundaries with flow direction...