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In large river ecosystems, the timing, extent, duration and frequency of floodplain inundation greatly affect the quality of fish and wildlife habitat and the supply of important ecosystem goods and services. Seasonal high flows provide connectivity from the river to the floodplain, and seasonal inundation of the floodplain governs ecosystem structure and function. River regulation and other forms of hydrologic alteration have altered the connectivity of many rivers with their adjacent floodplain – impacting the function of wetlands on the floodplain and in turn, impacting the mainstem river function. Conservation and management of remaining floodplain resources can be improved through a better understanding of...
This dataset features suitable habitat at discharges from 15,000 cfs to 100,000 cfs. The spatial extent for floodplain inundation modeling in the lower Trinity River was from Romayor, Texas, to approximately Moss Bluff, Texas. River sections were modeled using steady flow conditions. For the upper section, discharge and stage were both available for the two gages (Romayor USGS 08066500 and Liberty USGS 08067000). For the lower section, the Moss Bluff gage (USGS 08067100) is tidally-influenced, so gage height didn’t correspond to upstream changes in discharge. Depth rasters were exported from HEC-RAS 5.0.0. Since the lower section had large over- and underestimates, depth values were sampled along the intersection...
This dataset features inundated areas at discharges from 15,000 cfs to 100,000 cfs. The spatial extent for floodplain inundation modeling in the lower Trinity River was from Romayor, Texas, to approximately Moss Bluff, Texas. River sections were modeled using steady flow conditions. For the upper section, discharge and stage were both available for the two gages (Romayor USGS 08066500 and Liberty USGS 08067000). For the lower section, the Moss Bluff gage (USGS 08067100) is tidally-influenced, so gage height didn’t correspond to upstream changes in discharge. To model river stage specific inundation for the upper section, discharge for each Landsat 8 overpass date was entered as the upstream condition and the corresponding...
This dataset features suitable habitat connected to the main channel (based on floodplain inundation) within managed areas at discharges from 15,000 cfs to 100,000 cfs. The spatial extent for floodplain inundation modeling in the lower Trinity River was from Romayor, Texas, to approximately Moss Bluff, Texas. River sections were modeled using steady flow conditions. For the upper section, discharge and stage were both available for the two gages (Romayor USGS 08066500 and Liberty USGS 08067000). For the lower section, the Moss Bluff gage (USGS 08067100) is tidally-influenced, so gage height didn’t correspond to upstream changes in discharge. Depth rasters were exported from HEC-RAS 5.0.0. Since the lower section...
This model archive contains R source code for the Weighted-Multiple Linear Regression Program (WREG), input files, and associated output files needed to recreate regression models that are discussed in the associated report, U.S. Geological Survey Scientific Investigations Report 2023-5079 (https://doi.org/10.3133/sir20235079). More information and instructions for running the model archive are included in the README.txt file. Information regarding the WREG program can be found at: https://water.usgs.gov/software/WREG/.
The dataset includes flood-frequency data and related files for 211 streamgages operated by the U.S. Geological Survey (USGS) in Louisiana and parts of the surrounding states of Arkansas, Mississippi, and Texas as well as assembled explanatory variables (physical, climatic, and land-use characteristics of the basins). The data in this release were used in generalized least-squares (GLS ) regression analyses (Stedinger and Tasker, 1985) to generate equations used to predict annual exceedance probabilities (AEPs) at ungaged locations on streams in the study area (Ensminger and others, 2021). Flood-frequency analyses were conducted using annual peak-flow data from the 1877-2016 water years to estimate streamflows...
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Arkansas,
Hydrology,
Louisiana,
Mississippi,
Ouachita River,
Heavy rainfall occurred across Pennsylvania on September 1 and 2, 2021, as a result of the remnants of Hurricane Ida. Much of eastern and southcentral Pennsylvania received five to ten inches of rain and most of the rainfall occurred in a little more than six hours. Widespread substantial flooding occurred in the area, particularly impacted was the city of Philadelphia and surrounding areas. Flood frequencies were computed for 52 U.S. Geological Survey (USGS) streamgages impacted by the flooding in eastern and southcentral Pennsylvania using peak flow data through 2021. Flood documentation maps showing the extent and depth of flooding from the September 1-2, 2021, event were generated for five communities in southeastern...
This dataset features suitable depth (0.2 m ≤ depth ≤ 2.0 m) at discharges from 15,000 cfs to 100,000 cfs. The spatial extent for floodplain inundation modeling in the lower Trinity River was from Romayor, Texas, to approximately Moss Bluff, Texas. River sections were modeled using steady flow conditions. For the upper section, discharge and stage were both available for the two gages (Romayor USGS 08066500 and Liberty USGS 08067000). For the lower section, the Moss Bluff gage (USGS 08067100) is tidally-influenced, so gage height didn’t correspond to upstream changes in discharge. Depth rasters were exported from HEC-RAS 5.0.0. Since the lower section had large over- and underestimates, depth values were sampled...
The U.S. Geological Survey (USGS) has a long history of working cooperatively with the South Carolina Department of Transportation to develop methods for estimating the magnitude and frequency of floods for rural and urban basins that have minimal to no regulation or tidal influence. As part of those previous investigations, flood-frequency estimates have been generated at selected regulated streamgages. This is the data release for the report which assesses the effects of impoundments on flood-frequency characteristics by comparing annual exceedance probability (AEP) streamflows from pre- and post-regulated (before and after impoundment) periods at 18 USGS long-term streamgages, which is defined as a streamgage...
This dataset features floodplain depth (in meters) at discharges from 15,000 cfs to 100,000 cfs. The spatial extent for floodplain inundation modeling in the lower Trinity River was from Romayor, Texas, to approximately Moss Bluff, Texas. River sections were modeled using steady flow conditions. For the upper section, discharge and stage were both available for the two gages (Romayor USGS 08066500 and Liberty USGS 08067000). For the lower section, the Moss Bluff gage (USGS 08067100) is tidally-influenced, so gage height didn’t correspond to upstream changes in discharge. Depth rasters were exported from HEC-RAS 5.0.0. Since the lower section had large over- and underestimates, depth values were sampled along the...
This model archive contains R source code for the Weighted-Multiple Linear Regression Program (WREG), input files, and associated output files needed to recreate regression models that are discussed in the report: Levin, S.B. and Sanocki, C.A., Methods for estimating flood magnitude and frequency for unregulated streams in Wisconsin, U.S. Geological Survey Scientific Investigations Report 2022-5118 (https://doi.org/10.3133/sir20225118). More information and instructions for running the model archive are included in the README.txt file. Information regarding the WREG program can be found at: https://water.usgs.gov/software/WREG/.
This dataset features suitable habitat connected to the main channel (based on floodplain inundation) at discharges from 15,000 cfs to 100,000 cfs. The spatial extent for floodplain inundation modeling in the lower Trinity River was from Romayor, Texas, to approximately Moss Bluff, Texas. River sections were modeled using steady flow conditions. For the upper section, discharge and stage were both available for the two gages (Romayor USGS 08066500 and Liberty USGS 08067000). For the lower section, the Moss Bluff gage (USGS 08067100) is tidally-influenced, so gage height didn’t correspond to upstream changes in discharge. Depth rasters were exported from HEC-RAS 5.0.0. Since the lower section had large over- and...
The U.S. Geological Survey (USGS), in cooperation with the State of Hawaiʻi Department of Transportation, estimated flood magnitudes for the 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (AEP) for unregulated streamgages in Kauaʻi, Oʻahu, Molokaʻi, Maui, and Hawaiʻi, State of Hawaiʻi, using data through water year 2020. Regression equations which can be used to estimate flood magnitude and associated frequency at ungaged streams were developed.The methods and results of the study are published in a separate report (https://doi.org/10.3133/sir20235014). This data release includes two geographic information system (GIS) shapefiles, one of polygons representing the extents of the...
This dataset contains site information and results of flood-frequency analysis for 139 urban streamflow gaging stations (streamgages) operated by the U.S. Geological Survey (USGS) in Tennessee and parts of Alabama, Georgia, Mississippi, North Carolina, and South Carolina. Developed imperviousness in the basins, based on the 2011 National Land Cover Database, was at least 10 percent (Homer and others, 2015). Drainage areas of the streamgage basins ranged from 0.15 - 161 square miles. Annual peak-flow data from the 1947 - 2022 water years were used in the study (U.S. Geological Survey, 2024). Peak-flow (.pkf), specification (.psf), output (.PRT), and export (.EXP) files from flood-frequency analysis in USGS PeakFQ...
Alligator Gar, Atractosteus spatula, is an iconic species native to lowland floodplain river systems where they play an important role as top predators and by linking landscapes through their movement. Alligator Gar is also an important native fisheries species in the Trinity River. Disruption of river-floodplain connectivity is implicated in declining populations of Alligator Gar across much of its range. Successful management and conservation of Alligator Gar populations will be aided by an understanding of the relationship between flow and recruitment, particularly the availability and suitability of off-channel habitats utilized by this species for reproduction.
Categories: Data,
Project;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2015,
2016,
2017,
2018,
Academics & scientific researchers,
Reliable estimates of the magnitude and frequency of floods are an important part of the framework for hydraulic-structure design and flood-plain management. Annual peak flows measured at U.S. Geological Survey streamgages are used to compute flood-frequency estimates at those streamgages. However, flood-frequency estimates also are needed at ungaged stream locations. A process known as regionalization was used to develop regression equations to estimate the magnitude and frequency of floods at ungaged locations. This dataset contains the supporting tables and updated hydrologic region boundaries used in the 2017 flood-frequency study for Georgia, South Carolina, and North Carolina.
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Alabama,
Florida,
Georgia,
Hydrology,
North Carolina,
The U.S. Geological Survey (USGS), in cooperation with the State of Hawaiʻi Department of Transportation, estimated flood magnitudes for the 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (AEP) for unregulated streamgages in Kauaʻi, Oʻahu, Molokaʻi, Maui, and Hawaiʻi, State of Hawaiʻi, using data through water year 2020. Regression equations which can be used to estimate flood magnitude and associated frequency at ungaged streams were developed. The methods and results of the study are published in a separate report (https://doi.org/10.3133/sir20235014). This data release includes peak-flow, specification, output, and export files from version 7.3 of USGS PeakFQ software (Veilleux...
This dataset features inundated areas connected to the main channel at discharges from 15,000 cfs to 95,000 cfs. The spatial extent for floodplain inundation modeling in the lower Trinity River was from Romayor, Texas, to approximately Moss Bluff, Texas. River sections were modeled using steady flow conditions. For the upper section, discharge and stage were both available for the two gages (Romayor USGS 08066500 and Liberty USGS 08067000). For the lower section, the Moss Bluff gage (USGS 08067100) is tidally-influenced, so gage height didn’t correspond to upstream changes in discharge. To model river stage specific inundation for the upper section, discharge for each Landsat 8 overpass date was entered as the upstream...
Reliable estimates of the magnitude and frequency of floods are an important part of the framework for hydraulic-structure design and flood-plain management in Georgia, South Carolina, and North Carolina (study area). Annual peak flows measured at U.S. Geological Survey streamgages were used to compute at-site flood-frequency estimates at those streamgages in the study area based on annual peak-flows records through 2017. Flood-frequency estimates also are needed at ungaged stream locations. A process known as regionalization was used to develop regression equations to estimate the magnitude and frequency of floods at ungaged locations. This model archive provides the inputs and outputs for (1) the at-site flood-frequency...
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Alabama,
Florida,
Georgia,
Hydrology,
North Carolina,
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