Filters: Types: OGC WMS Layer (X) > partyWithName: Kristina G Hopkins (X) > Categories: Data (X)
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This dataset contains the daily average base flow, as determined by hydrograph separation, for 14 watersheds in Gwinnett County, Georgia for October 2001 through September 2020. Hydrograph separations were done using the Web-based Hydrograph Analysis Tool (WHAT) using the simple local minimum method on the daily average streamflows, which are also provided in this dataset. Base flow along with the calculated base-flow index (the proportion of base flow to total flow) were used to characterize groundwater recharge and the relative degree of storm runoff in the watersheds. Base flow was also used as predictor variable in models for estimating streamwater constituent loads for 12 water-quality constituents at 13 of...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Gwinnett County,
State of Georgia,
datasets,
inlandWaters,
streamflow,
This dataset contains a list of outlier sample concentrations identified for 17 water quality constituents from streamwater sample collected at 15 study watersheds in Gwinnett County, Georgia for water years 2003 to 2020. The 17 water quality constituents are: biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), suspended sediment concentration (SSC), total nitrogen (TN), total nitrate plus nitrite (NO3NO2), total ammonia plus organic nitrogen (TKN), dissolved ammonia (NH3), total phosphorus (TP), dissolved phosphorus (DP), total organic carbon (TOC), total calcium (Ca), total magnesium (Mg), total copper (TCu), total lead (TPb), total zinc (TZn), and total dissolved solids...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Gwinnett County,
State of Georgia,
inlandWaters,
surface water quality
Montgomery County, Maryland Department of Environmental Protection has collected datasets to assess the health of streams since the early 1990s. Datasets include geomorphic stream cross-sectional surveys, fish and benthic macroinvertebrate counts and taxa abundance, and water chemistry data collected at the time of benthic and fish sampling (dissolved oxygen, pH, specific conductance, air temperature, and water temperature). Data span years 1992 to 2020 at five watersheds within the Clarksburg study area. Watersheds include a forested reference site (Soper), an urban site with centralized stormwater management (Crystal Rock), and three treatment watersheds (TR104, TR109, and Cabin Branch) within the Clarksburg Special...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Clarksburg,
Maryland,
Montgomery County,
Montgomery County,
USGS Science Data Catalog (SDC),
As part of a collaborative study with the City of Raleigh, North Carolina, the U.S. Geological Survey is assessing streambank erosion potential in selected stream reaches throughout the Greater Raleigh metropolitan area. Rapid field measurement techniques were used to assess streambank stability at 124 stream segments between January and March 2022. Field data were collected using the Bank Erosion Hazard Index (BEHI) and Near Bank Stress (NBS) assessment methods (Rosgen, 2001; Rosgen and others, 2008) as well as the Rapid Geomorphic Assessment (RGA) method (Simon and others, 2007). This Data Release contains a dataset with all stream site information, field measurements, and streambank stability assessment results;...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service,
Shapefile;
Tags: Geomorphology,
Geomorphology,
Hydrology,
Land Use Change,
Raleigh, North Carolina,
As part of a collaborative study with the City of Raleigh, North Carolina, the U.S. Geological Survey developed a drainage network for the Greater Raleigh Area, North Carolina using the most recent available lidar data, representing the years 2015 and 2022. This dataset includes the delineated drainage network (drainage_network.zip) and rasters representing the breached and filled digital elevation model (raleigh_dem_fil.tif), the flow accumulation raster (raleigh_d8_fac.tif), and the flow direction raster (raleigh_d8_fdr.tif). Raster files are available as Cloud Optimized GeoTIFFs, meaning they are formatted to work on the cloud or can be directly downloaded. The drainage network was delineated for all locations...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Geomorphology,
Hydrology,
North Carolina,
Raleigh,
Remote Sensing,
The dataset contains model coefficients and statistics for the 488 regression models used to estimate streamwater constituent loads for 13 watersheds in Gwinnett County, Georgia for two calibration periods, water years 2003-2010 and 2010-2020. Model terms were selected from an 11-parameter equation, which was a function of discharge, base flow, season, turbidity, and time (trend), using a forward stepwise ordinary least squares regression approach. Model coefficients were fit using U.S. Geological Survey (USGS) LOADEST load estimation software. Models were fit both with and without turbidity explanatory variables for 12 water-quality constituents: total suspended solids, suspended sediment concentration, total nitrogen,...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Gwinnett County,
State of Georgia,
inlandWaters,
mathematical modeling,
streamflow,
This dataset contains the percentage of 14 National Land Cover Database (NLCD) land cover classes within the drainage areas of 15 watersheds in Gwinnett County, Georgia from 2001 to 2019. The dataset includes scenes from eight years, 2001, 2004, 2006, 2008, 2011, 2013, 2016, and 2019, which were analyzed using a consistent approach so that they could be used to assess land cover changes. The NLCD dataset is derived from Landsat imagery and has a grid size of 30 meters. The fourteen land cover classes were categorized into eight land cover groups to simplify the presentation of watershed land cover characteristics (1. developed, low intensity; 2. developed, medium intensity; 3. developed, high intensity; 4. developed,...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Gwinnett County,
State of Georgia,
environment,
imageryBaseMapsEarthCover,
inlandWaters,
10: Laboratory standard reference samples for the Gwinnett County, Georgia study for years 2014-2020
This dataset contains laboratory standard reference sample concentrations analyzed by RTI Laboratories, the analytical laboratory used by the Gwinnett County, Georgia study. These water-quality-control samples are part of the U.S. Geological Survey (USGS) Standard Reference Samples (SRS) Project inter-laboratory comparison study. RTI Laboratories sample concentrations along with the included inter-laboratory result statistics (for most probable value and standard error) can be used to assess the laboratory’s analytical precision and bias. Sample concentrations are reported for 12 constituents for 13 round-robin sample rounds, in which prepared samples are sent to participating laboratories twice per year, and were...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Gwinnett County,
State of Georgia,
inlandWaters,
laboratory quality control,
materials standards,
The dataset contains annual and model calibration period streamwater constituent load and yield estimates for 13 watersheds in Gwinnett County, Georgia for the water years 2003 to 2020. Loads and yields were estimated for 12 water-quality constituents: total suspended solids, suspended sediment concentration, total nitrogen, total nitrate plus nitrite, total phosphorus, dissolved phosphorus, total organic carbon, total calcium, total magnesium, total lead, total zinc, and total dissolved solids. The USGS LOADEST load estimation software, which employs a regression-model estimation approach, was used for constituents that had at least a minimal relation with the model explanatory variables, as indicated by concentration...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Gwinnett County,
State of Georgia,
inlandWaters,
mathematical modeling,
streamflow,
This table contains estimates for upland sediment erosion and delivery to the stream estimated using a modified Revised Universal Soil Loss Equation 2 (RUSLE2) approach (USDA-ARS, 2013). Upland erosion (Eu) was calculated as the sum of the product of the erosivity factor (Rm) estimated for each month, the soil erodibility factor (K), the length-slope factor (LS), C-factor (Cm) for each month, farming support practices (P) assumed to be 1, and the area of each land cover grouping in acres. Rasters with 10-m resolution were created for these five variables in the modified RUSLE2 equation to create an upland erosion (Eu) raster for the study area. Data were calculated for each National Hydrography (NHD) Dataset Version...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Difficult Run,
Fairfax County,
South Fork Little Difficult Run,
Virginia,
erosion,
This dataset contains quality assurance sample concentrations for 19 constituents for the 15 monitored watersheds in Gwinnett County, Georgia, from 2000 to 2020. Samples include 431 replicate pairs and 335 field blanks. Replicate sampling allows for comparison of water quality to assess the combined variability in sample representativeness and laboratory precision and can also be used to identify possible sample contamination. Field blanks, samples of deionized “blank” water collected using the same sampling equipment and similar methodology as routine samples, were used to identify any possible contamination from field collection equipment and methodology.
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Gwinnett County,
State of Georgia,
inlandWaters,
surface water quality,
water quality,
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Clarksburg,
Land Change Science,
Land Use Change,
Maryland,
Montgomery County,
This dataset contains population densities of 15 study watersheds in Gwinnett County, Georgia from 2000 to 2020. Population densities were determined for 2000, 2010, and 2020 from the decadal U.S. Census and for 2012 and 2017 from the American Community Survey 5-year estimates of 2010-14 and 2015¬-19 block group data, respectively. Population density within each watershed was determined by clipping the census block group data by the watershed boundaries and area-weighting the block group population density data within each watershed. Census block group data is the smallest geographic unit for which the census provides data.
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Gwinnett County,
State of Georgia,
population (human),
society,
watershed
This dataset contains the estimation data that was used in combination with the regression models to estimate streamwater constituent loads for 12 water-quality constituents for 13 watersheds in Gwinnett County, Georgia for the water years 2003 to 2020. Load were estimated using the U.S. Geological Survey (USGS) LOADEST load estimation software. Variables in the estimation dataset include a storm condition indicator variable, streamflow, streamflow during base-flow conditions, base flow, turbidity, and turbidity during stormflow conditions. Variants of the streamflow variable were used depending on whether the regression models were fit with turbidity explanatory variables. The time-step of the estimation datasets...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Gwinnett County,
State of Georgia,
inlandWaters,
mathematical modeling,
streamflow,
The dataset contains the sample constituent concentrations and explanatory variable values used for fitting the load regression models that were then used to estimate streamwater constituent loads for 13 watersheds in Gwinnett County, Georgia for water years 2003 to 2020. Load regression models were fit using U.S. Geological Survey (USGS) LOADEST load estimation software. Models were fit for 12 water-quality constituents: total suspended solids, suspended sediment concentration, total nitrogen, total nitrate plus nitrite, total phosphorus, dissolved phosphorus, total organic carbon, total calcium, total magnesium, total lead, total zinc, and total dissolved solids. Explanatory variables include a storm condition...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Gwinnett County,
State of Georgia,
inlandWaters,
mathematical modeling,
streamflow,
This dataset describes streamflow and precipitation event statistics for four watersheds located in Clarksburg, Maryland, USA. Streamflow and precipitation events were identified from fourteen years of sub-daily (5- and 15-minute) monitoring data from October 1, 2004 through September 30, 2018. A 6-hour inter-event window was used to define discrete streamflow and precipitation events. The following streamflow metrics were calculated for each event area normalized peak streamflow, runoff yield, runoff ratio, streamflow duration, time to peak, and rise rate. Precipitation event metrics include total precipitation depth and precipitation event duration.
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Clarksburg,
Germantown,
Hydrology,
Land Change Science,
Land Use Change,
This dataset contains the number of buildings and their construction dates within the 15 study watersheds in Gwinnett County, Georgia. Dataset reflects existing buildings as of October 2021 and construction dates range from 1810 to 2021. The dataset was created by matching parcel boundaries obtained from Gwinnett County with building construction dates from the Gwinnett County Cadastral database. Building densities were calculated for each watershed and year to estimate temporal changes in watershed building densities.
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Gwinnett County,
State of Georgia,
buildings,
imageryBaseMapsEarthCover,
land use and land cover,
This dataset contains the percentages of impervious areas within the drainage areas of 15 watersheds in Gwinnett County, Georgia from 2000 to 2020. The dataset includes data from 16 years, 2000, 2005, 2006, and annually from 2008 to 2020. The dataset was derived from impervious area coverages provided from the Gwinnett County Department of Public Utilities. These coverages were determined from 1:1,200-scale aerial photography with a 1-meter square grid size created by digitizing polygons of impervious surfaces. Watershed imperviousness was determined for various land cover types that were provided with the impervious area coverages. These included transportation and buildings land cover types for all impervious...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Gwinnett County,
State of Georgia,
imageryBaseMapsEarthCover,
impervious area,
inlandWaters,
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