This U.S. Geological Survey data release consists multiple datasets used to simulate the extents of flood inundation along the Muddy River, near Moapa, Nevada. Flood-inundation extents equal the maximum area of flood inundation and were estimated using a coupled one-dimensional (1D) and two-dimensional (2D) hydraulic model. The modeled extents represent six annual exceedance probabilities simulated for the current (2019) levee location adjacent to the Muddy River and a new levee location associated with a proposed restoration of a selected reach along the Muddy River. The data release includes: 1) a polygon dataset of the flood-inundation extents (MuddyRiver_Flood_Inundation_p.shp); 2) a zip file containing all relevant files to document and run the PeakFQ flood-frequency analysis used as input into the hydraulic model (0941600_Flood_Frequency_Archive.zip); 3) a zip file containing all relevant files to document and run the coupled 1D and 2D Hydrological Engineering Center-River Analysis System (HEC-RAS) hydraulic model used to generate a polygon dataset of flood-inundation extents (SWmodel_Archive.zip); 4) a polygon dataset of the current and proposed levee locations (MuddyRiver_Levee_p.shp); 5) a point dataset of survey points (RTK-TS_survey_x.shp) collected from April 1 to August 9, 2019, using real-time kinematic global navigation satellite system (GNSS) and total station (TS); and 6) a point dataset of seven static reference locations (Static_GNSS_x.shp) collected from March 29 to August 9, 2019, using a single-baseline online positioning user service – static (OPUS-S) GNSS survey.

This model archive contains all relevant files to run and document the Hydrological Engineering Center-River Analysis System (HEC-RAS) coupled one and two-dimensional hydraulic model used to simulate flood-inundation extents for the Muddy River, near Moapa, Nevada. The HEC-RAS model was applied to simulate flood-inundation extents for a current (2019) levee location and for a new location location proposed as part of a river restoration plan. The model archive includes information on: 1) stage-streamflow rating used for model calibration (calibration_targets); 2) the model run and output files (model_files); and 3) the 32-bit executable installation file for HEC-RAS 6.1 used to run the simulations (HEC-RAS_61.Setup.exe); 4) the modeling software version and website (model-software-version.txt); 5) the model bounding box coordinates (modelgeoref.txt); 6) an overview of how to run the model and all the files and folders in SWmodel_Archive.zip (README.txt).

This archive contains all relevant files to run and document the flood-frequency analysis using the PeakFQ 7.3 software for estimating the annual exceedance probability streamflows for U.S. Geological Survey streamgage 09416000 - Muddy River near Moapa, Nevada. The archive includes: 1) the PeakFQ input file (09416000_peak.txt); 2) the PeakFQ output file (09416000_PEAK.PRT); 3) the PeakFQ specifications file (09416000_PEAK.PSF); 4) the PeakFQ input data graph file (09416000_inp.EMF); 5) the PeakFQ Annual exceedance probability plot file (094196000.EMF); 6) the summary table documenting the flood-frequency (09416000_Flood_Frequency.xlsx);

This polygon shapefile represents model simulated flood-inundation extents for the Muddy River, near Moapa Nevada. A flood frequency analysis was performed at USGS streamgage 09416000 - Muddy River near Moapa, Nevada, to estimate the 50, 20, 10, 4, 2, and 1-percent annual exceedance probability (AEP) flood streamflows. The flood-inundation extents for the 50-, 20-, 10-, 4-, 2-, and 1-percent AEP floods were simulated for the current levee location in 2019 and for the new levee location of the proposed restoration. One model simulation represents the levee at its current (existing) location in 2019 on the east bank of the river and referred to as ‘current conditions (2019).’ A second model simulation removes the existing levee and represents the new levee location farther away from the river on the east side of the proposed restoration area. The second model simulation is referred to as the ‘proposed restoration conditions.’ Both model simulations had the same flood-hydrographs, hydraulic structures, and roughness coefficients; however, the topography data used for each model simulation was adjusted to represent differing locations of the existing and proposed levees. Flood-inundation extents were simulated with a coupled 1-D- and 2-D unsteady hydraulic model in the Hydrologic Engineering Center’s River Analysis System (HEC-RAS) computer program. Those locations where the water-surface was higher than the land surface were defined as inundated. The inundation polygons are named by AEP flow (50, 20, 10, 4, 2, 1-percent) and condition (current and proposed restoration).

This polygon shapefile represents model simulated flood-inundation extents for the Muddy River, near Moapa Nevada. A flood frequency analysis was performed at USGS streamgage 09416000 - Muddy River near Moapa, Nevada, to estimate the 50, 20, 10, 4, 2, and 1-percent annual exceedance probability (AEP) flood streamflows. The flood-inundation extents for the 50-, 20-, 10-, 4-, 2-, and 1-percent AEP floods were simulated for the current levee location in 2019 and for the new levee location of the proposed restoration. One model simulation represents the levee at its current (existing) location in 2019 on the east bank of the river and referred to as ‘current conditions (2019).’ A second model simulation removes the existing levee and represents the new levee location farther away from the river on the east side of the proposed restoration area. The second model simulation is referred to as the ‘proposed restoration conditions.’ Both model simulations had the same flood-hydrographs, hydraulic structures, and roughness coefficients; however, the topography data used for each model simulation was adjusted to represent differing locations of the existing and proposed levees. Flood-inundation extents were simulated with a coupled 1-D- and 2-D unsteady hydraulic model in the Hydrologic Engineering Center’s River Analysis System (HEC-RAS) computer program. Those locations where the water-surface was higher than the land surface were defined as inundated. The inundation polygons are named by AEP flow (50, 20, 10, 4, 2, 1-percent) and condition (current and proposed restoration).

This polygon shapefile represents the boundaries of the current (2019) and proposed levee locations used to simulate flood-inundation extents for the at Muddy River, near Moapa, Nevada. The new levee location is proposed as part of a river restoration plan for selected reaches of the Muddy River.

The U.S. Geological Survey (USGS), in cooperation with the city of Harrisonville, Missouri, assessed flooding of Muddy Creek resulting from varying precipitation magnitudes and durations, antecedent soil moisture conditions, and channel conditions. The precipitation scenarios were used to develop a library of flood-inundation maps that included a 3.8-mile reach of Muddy Creek and tributaries within and adjacent to the city. Hydrologic and hydraulic models of the upper Muddy Creek Basin were used to assess streamflow magnitudes associated with simulated precipitation amounts and the resulting flood-inundation conditions. The U.S. Army Corps of Engineers Hydrologic Engineering Center-Hydrologic Modeling System (HEC–HMS; version 4.4.1) was used to simulate the amount of streamflow produced from a range of rainfall events. The Hydrologic Engineering Center-River Analysis System (HEC–RAS; version 5.0.7) was then used to route streamflows and map resulting areas of flood inundation. The hydrologic and hydraulic models were calibrated to the September 28, 2019; May 27, 2021; and June 25, 2021, runoff events representing a range of antecedent moisture conditions and hydrologic responses. The calibrated HEC–HMS model was used to simulate streamflows from design rainfall events of 30-minute to 24-hour durations and ranging from a 100- to 0.1-percent annual exceedance probability. Flood-inundation maps were produced for USGS streamflow stages of 1.0 feet (ft), or near bankfull, to 4.0 ft, or a stage exceeding the 0.1-percent annual exceedance probability interval precipitation, using the HEC–RAS model. The consequence of each precipitation duration-frequency value was represented by a 0.5-ft increment inundation map based on the generated peak streamflow from that rainfall event and the corresponding stage at the Muddy Creek stage reference location. Seven scenarios were developed with the HEC–HMS hydrologic model with resulting streamflows routed in a HEC-RAS hydraulic model and these scenarios varied by antecedent soil-moisture and channel conditions. The same precipitation scenarios were used in each of the seven antecedent moisture and channel conditions and the simulation results were assigned to a flood-inundation map condition based on the generated peak flow and corresponding stage at the Muddy Creek reference location. This data release includes: 1) tables summarizing the model results including the flood-inundation map condition of each model scenario for dry (CNI; Muddy_Creek_summary_table_1_1.csv), normal (CNII; Muddy_Creek_summary_table_1_2.csv), and wet (CNIII; Muddy_Creek_summary_table_1_3.csv) antecedent soil moisture conditions (MuddyCreek_summary_tables.zip); 2) a shapefile dataset of the streamflow inundation extents at Muddy Creek reference location stages of 1.0 to 4.0 feet (MuddyCreek_inundation_extents.zip containing MudHarMO.shp); 3) a raster dataset of the streamflow depths at Muddy Creek reference location stages of 1.0 to 4.0 feet (MuddyCreek_inundation_depths.zip containing MudharMO_X.tif where X = 1,2,3,4,5,6,7 corresponding to inundation map stages of 1.0, 1.5 , 2.0, 2.5, 3.0, 3.5, 4.0 feet)); 4) tables of hydrologic and hydraulic model performance and calibration metrics, locations of continuous pressure transducers (PTs; MuddyCreek_PT_locations.zip) and high-water marks (HWMs; MuddCreek_HWM_locations.zip) used in assessment of model calibration and validation, and time series of pressure transducer data (MuddyCreek_PT_time_series.zip) found in MuddyCreek_model_performance_calibration_metrics.zip; 5) hydrologic and hydraulic model run files used in the simulation of dry hydrologic response conditions (CN_I conditions) and effects of proposed detention storage (MuddyCreek_dry_detention.zip); 6) hydrologic and hydraulic model run files used in the simulation and calibration of dry hydrologic response conditions (CN_I conditions) and current (2019) existing channel conditions

This point shapefile contains positional data for 2,205 locations at the Muddy River, near Moapa, Nevada, April 1 to August 9, 2019. Positional data were collected using either a single-base real-time kinematic (RTK) global navigation satellite system (GNSS) or a total station. The survey data primarily were used to define 105 cross-sections, with a secondary use as vertical precision verification for lidar data.

This point shapefile contains positional data for 2,205 locations at the Muddy River, near Moapa, Nevada, April 1 to August 9, 2019. Positional data were collected using either a single-base real-time kinematic (RTK) global navigation satellite system (GNSS) or a total station. The survey data primarily were used to define 105 cross-sections, with a secondary use as vertical precision verification for lidar data.

The development and generation of the datasets that are published in this data release, were based on the methods and findings of the report: Kohn, M.S. and Patton, T.T., 2018, Flood-Inundation Maps for the South Platte River at Fort Morgan, Colorado, 2018: U.S. Geological Survey Scientific Investigations Report 2018-5114, 14 p., https://doi.org/10.3133/sir20185114. The geospatial datasets contain final versions of the raster and vector geospatial data and related metadata, and the model archive dataset contains all relevant files to document and re-run the surface-water hydraulic model that are discussed in the report. Digital flood-inundation maps for a 4.5-mile reach of the South Platte River at Fort Morgan, Colorado from Morgan County Road 16 to Morgan County 20.5, were created by the U.S. Geological Survey (USGS) in cooperation with the Colorado Water Conservation Board. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science web site (https://water.usgs.gov/osw/flood_inundation/), depict estimates of the areal extent and depth of flooding corresponding to select water levels (stages) at USGS streamgage 06759500, South Platte River at Fort Morgan. Current conditions for estimating near-real-time areas of inundation using USGS streamgage information are available through the National Water Information System web interface or the National Weather Service (NWS) Advanced Hydrologic Prediction Service (http:/water.weather.gov/ahps/). Water-profiles were computed for the stream reach by means of a one-dimensional, step-backwater model. The September 15, 2013 and May 20, 2017 floods were used to calibrate the model, and the June 15, 2015 and May 29, 2017 floods were used to independently validate the model. Nine pressure transducers were deployed to record the stage at nine different locations along the reach and to document the floods of May 20 and 29, 2017 at the South Platte River at Fort Morgan streamgage. The calibrated hydraulic model was then used to determine 16 water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from 12 ft (3.66 m) or below bankfull to 27 ft (8.23 m), which is 1 ft (0.3 m) greater than the highest recorded water level (25.73 ft [7.84 m] on September 15, 2013) at the South Platte River at Fort Morgan streamgage during its period of record and the 2013 flood exceeds the major flood stage of 21.5 ft (6.55 m) by more than 4 ft (1.2 m) as defined by the National Weather Service. The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from light detection and ranging) to delineate the area flooded at stages ranging from 12-ft to 27-ft. The availability of these inundation maps, along with internet information regarding the current stage from the USGS streamgage 06759500, South Platte River at Fort Morgan, Colorado, and forecast river stages from the NWS Advanced Hydrologic Prediction Service, provides emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.