A 2D Hydraulic model (HEC-RAS) for below Tuttle Creek Reservoir at the confluence of the Kansas River and the Big Blue River near Manhattan, KS is presented. Model geometry is based on United States Geological Survey (USGS) 3DEP data (2015), with underwater bathymetry “burned†in using cross-sections sampled in the field in April of 2023. The model was calibrated based on water surface measured during data collection. The hydraulic simulations correspond to streamflows during which fish monitoring data were collected by researchers at Kansas State University (L. Rowley and K. Gido, to be published). Results from the hydraulic model, coupled with a sediment transport model, will be used to study fish and macroinvertabrate ecological response to streamflow., The following is a summary of data utilized for developing a bathymetric terrain for 2D hydraulic modeling using HEC-RAS. Data used for model calibration and validation is also discussed. Available Data Cross-section elevation data were collected by the United States Army Corps of Engineers (USACE) Kansas City District at approximately 200-foot to 1000-foot increments at the confluence of the Big Blue River and the Kansas River near Manhattan, Kansas. The following equipment was used by two complete surveying teams: • Ohmex SonarMite single beam echo sounder SFX @ 200khz, • Ohmex SonarMite single beam echo sounder DFX @ 28kHz & 200kHZ, • Trimble R12i 0096 & 0098, • Trimble R8 1984 & 6282  The cross-section elevation data were collected by boat and supplemented by hand-carried, pole-mounted Trimbles on April 10 to 14, 2023. The USGS gage on the Big Blue River near Manhattan, KS (06887000) had an average discharge of 425 cfs during the field collection time period (Figure ..., , # Hydraulic model (HEC-RAS) of downstream of Tuttle Creek Reservoir at the confluence of the Big Blue River and the Kansas River near Manhattan, KS

https://doi.org/10.5061/dryad.k3j9kd5gr

Description of the data and file structure

Many of the files are specific to HEC-RAS and may be opened with HEC-RAS 6.3.1 or later version. HDF (Hierarchical data format) are datasets that can be opened with an alternative software such as that provided by https://support.hdfgroup.org/products/java/hdfview/

(Enclosed files listed alphabetically)

• Backup.p01: HEC-RAS-generated backup of the Plan file. This associates inputs with simulation options in HEC-RAS
• LandcoverB_122223.hdf: Contains the landcover used for the simulation.
• LandcoverB_122223.tiff: Landcover for the simulation in a raster format.
• Terrain_121123.hdf: Contains the terrain used for the simulation, bathymetry was "burned" in a...

This model is a two-dimensional (2D) hydraulic model created in the Hydraulic Engineering Center’s River Analysis System (HEC-RAS). The model was created for a segment of the San Saba River between Harkeyville and San Saba, TX, USA. The model’s geometry is based on United States Geological Survey 3D Elevation Program data collected in 2018, and the channel bathymetry was burned in using cross-sectional data collected by Texas State University researchers in 2018. The model was calibrated using water surface elevation and velocity measurements taken during field data collection. Methods Available data: Researchers from Texas State University collected depth, flow velocity, and wetted width data at 200 cross-sections spaced approximately 350 ft apart using the equipment listed in Table 1. Table 1. Equipment used and their accuracy for Texas State University data collection. Table from Harris et al. (2023).

Parameter

Equipment

Unit Accuracy

Location

GPSMap 64 Handheld GPS

10-50 feet

Velocity

Hach Velocity Meter (Model FH950.1)

0.1 feet/second

Depth

An adjustable “ruler” stick with feet as units

0.1 feet

Wetted Width

Laser Technology Inc. TruPulse 360r

3 feet to nonideal (natural) target

Data was collected between June 4th and June 27th, 2018. During this time period, USGS gage 08146000 (San Saba, TX) recorded discharges ranging from 11.9 to 396 cfs, with an average discharge of 20 cfs. USGS 3DEP 1 m resolution data collected between February 14th and April 22nd, 2018, was used to create the HEC-RAS terrain (Merrick-Surdex 2018). Discharge at USGS gage 08146000 ranged from 40.5 to 966 cfs during this time period. For much of the time period, the discharge was approximately 60 cfs. Bathymetric areas: The 3DEP data was imported as a terrain in HEC-RAS v.6.2, and field-collected cross sections were burned into the channel following methods from Harris et al. (2023). The 95 most upstream sites in the segment were associated with a single depth measurement in the center of the channel, whereas the remaining 105 cross sections were associated with three depth measurements collected in the center of the channel and on the left and right, although the position of measurements were not recorded. For cross sections that had three depth measurements, if the standard deviation of the depth exceeded 0.25 ft, all three measurements were used to delineate the cross section in HEC-RAS. For all other cross sections, a single depth was used to delineate the cross section (either the single available depth measurement or the average depth based on three measurements; Harris et al., 2023). A final bathymetric/topographic surface was generated following Harris et al. (2023) using inverse distance weighted interpolation with the field-collected cross sections to estimate channel bathymetry. Landcover was delineated using aerial photography (USDA 2018) and associated Manning’s N roughness values were determined following Chow (1959) and Harris et al. (2023) (Table 2). Table 2. Selected Manning’s N roughness values based on delineated landcover. Adapted from Harris et al. (2023).

Landcover Description

Chow 1959 Description, which has minimum/normal/maximum ranges (Manning's n Values (orst.edu))

Selected Roughness

Channel

(Main channel or Mountain Streams)

Channel

Sluggish reaches, weedy, deep pools (normal)

0.07

Channel2

clean, winding, some pools and shoals, some weeds and more stones (maximum)

0.05

Channel3

Clean, straight, full stage, no rifts or deep pools (minimum)

0.025

Cobbly3

No vegetation in channel, banks usually steep, trees and brush along banks submerged at high stages, bottom: gravel, cobbles, and few boulders (minimum)

0.03

Ineffective Sec2

Sluggish reaches, weedy, deep pools (maximum)

0.08

Ineffective Sec3

Very weedy reaches, deep pools, or floodways with heavy stand of timber and underbrush (normal)

0.1

Ineffective Sec4

Very weedy reaches, deep pools, or floodways with heavy stand of timber and underbrush (maximum)

0.15

Intermediate Zone

(Floodplains)

Grassy Floodway

Scattered brush/heavy weeds (maximum) or light brush and trees in summer (between normal and maximum)

0.07

Floodplain

(Floodplains)

Dense Woody

Dense willows, summer straight (minimum) or heavy stand of timber, downed trees, little undergrowth (normal)

0.1

Dense Woody2

Dense willows, summer straight (normal)

0.2

Sparse Shrub

Light to dense brush (Various definitions, ranges from minimum to maximum)

0.08

NoData

Scattered brush, heavy weeds (between normal and maximum)

0.06

A 2-D HECRAS mesh was created following Harris et al. (2023) with a mesh size of 40 square feet and a breakline with cell size of 20 feet located in the center of the channel. A 12 cfs unsteady flow simulation was run as a “hot-start” to fill the modeled channel and subsequently used as the initial conditions for additional flows simulated for the segment. Because the discharge recorded at USGS gage 08146000 varied during the field sampling period, different sections of the segment were calibrated to different discharges to match field conditions at the time of data collection (Table 3). Table 3. Discharges used to calibrate 2-D HEC-RAS model based on discharges recorded at USGS gage 08146000 during field collection dates in 2018.

Calibration discharge (cfs)

Average field discharge (cfs)

Range of field discharges (cfs)

Dates (2018)

Cross section

12

12.5

9.7-15.6

6/25; 6/27

29370-20044; 8279-467

16

15.9

13.5-17.4

6/21; 6/26

19597-8667

20

20

16.8-22.4

6/13-6/14; 6/20

49011-29699

26

26.5

21.1-30.3

6/12

56420-49340

34

33.8

30.3-36.5

6/11

63009-56840

40

40.3

20.6-114

6/4

72209-63766

Calibration was conducted in accordance with methods from Harris et al. (2023), with an initial channel roughness of 0.07 adjusted on a case-by-case basis throughout the segment based on comparisons of field-measured and modeled depth and velocity at cross sections. In addition, modeled channel widths were compared to aerial imagery for select discharges, and floodplain roughness was adjusted as needed in an attempt to match channel width from imagery (USDA, 2004-2018; Table 4). Table 4. Average discharge recorded at USGS gage 08146000 on select dates when aerial imagery from the National Agricultural Inventory Program (NAIP) was available (USDA, 2004-2018), used for comparison of imagery channel width with modeled channel width.

Discharge (cfs)

Imagery

Imagery date

12.5

NAIP

August 16th, 2006

22

NAIP

July 12th, 2014

54

NAIP

July 31st, 2010

86

NAIP

August 3rd, 2016

241

NAIP

December 12th, 2004

1600

NAIP

October 26th, 2018

The final overall root mean-squared error of the model after calibration was 0.31 ft s-1 for velocity and 0.34 ft for depth. Error at individual cross sections was also recorded for reference purposes. Summary of assumptions: This HEC-RAS model has assumptions matching those of Harris et al. (2023). Discharge data from 2018 at USGS gage 08146000 (San Saba, TX) have been approved by USGS. Usage notes: HEC-RAS 6.2 is a free hydraulic analysis software available for download from the U.S. Army Corps of Engineers. References: Chow VT. Open-channel hydraulics: New York: McGraw-Hill; 1959. Harris A, Wiest S, Cushway KC, Mitchell ZA, Schwalb AN. Hydraulic model (HEC-RAS) of the Upper San Saba River between For McKavett and Menard, TX [Dataset]. Dryad Data Repository; 2023. https://doi.org/10.5061/dryad.pc866t1tt. Merrick-Surdex. Lidar Mapping Report. 2018. Prepared for United States Geological Survey contract G16PC0029. Mitchell ZA. The role of life history strategies and drying events in shaping mussel communities: a multiscale approach [dissertation]. San Marcos (TX): Texas State University. 2020. Mitchell ZA, Cottenie K, Schwalb AN. Trait-based and multi-scale approach provides insight on responses of freshwater mussels to environmental heterogeneity. Ecosphere. 2023; 14(7):e4533. https://doi.org/10.1002/ecs2.4533. Mitchell ZA, Schwalb AN, Cottenie K. Trait-based and multi-scale approach provides insight on responses of freshwater mussels to environmental heterogeneity [Dataset]. Dryad Data Repository; 2023. https://doi.org/10.5061/dryad.msbcc2g3d. United States Department of Agriculture (USDA). Texas NAIP Imagery, 2018. Web. 2022-03-09.

This is a 2D Hydraulic model (HEC-RAS) for the Upper San Saba River between Fort McKavett and Menard, TX. Model geometry is based on USGS 3DEP data (2018), with underwater bathymetry “burned†in using cross-sections sampled in the field in 2018. The model was calibrated based on water surface and velocities measured during data collection., The following is a summary of available data utilized for developing a bathymetric terrain for 2D hydraulic modeling using HEC-RAS. Data available for model calibration and validation is also discussed. Available Data Cross-section data was collected at approximately 350-foot increments with the following devices: Table 1. Equipment used and their accuracy for field data collection.

Parameter

Equipment

Unit Accuracy

Location

GPSMap 64 Handheld GPS

10-50 feet

Velocity

Hach Velocity Meter (Model FH950.1)

0.1 feet/second

Depth

An adjustable “ruler†stick with feet as units

0.1 feet

Wetted Width

Laser Technology Inc. TruPulse 360r

3 feet to nonideal (natural) target

The data was collected from July 10 to 26, 2018. The USGS Gage on the San Saba River at Menard, TX (08144500) shows discharges varied from 8 to 18 cfs during the time period. USGS 3DEP data was used in the HEC-RAS terrain. These data were collected at a 1-meter resolution over a period..., HEC-RAS 6.2 is a free hydraulic analysis software available from US Army Corps of Engineers., # Hydraulic model (HEC-RAS) of the Upper San Saba River between Fort McKavett and Menard, TX

Description of the data and file structure

Many of the files are specific to HEC-RAS and may be opened with HEC-RAS 6.2 or later version. HDF (Hierarchical data format) are datasets that can be opened with an alternative software such as that provided by https://support.hdfgroup.org/products/java/hdfview/ (Enclosed files listed alphabetically)

• Backup.p01: HEC-RAS-generated backup of the Plan file. This associates inputs with simulation options in HEC-RAS
• IDW_Terrain.hdf: Contains the terrain used for the simulation, bathymetry was "burned" in and computed via Inverse Distance Weighted method described in the attached report.
• IDW_Terrain.Merge_Apr15.tiff: Terrain for the simulation in a raster format.
• IDW_Terrain.vrt: Terrain for the simulation as a GDAL virtual format (vrt) as terrains can sometimes be composed of multiple raster datasets (not in this case).
• Landcover.hdf: Co...

This dataset includes 4 sets of velocity measurements and water-surface elevation measurements collected at the Wallens Bend (WB) reach on the Clinch River near Kyles Ford, Tennessee between April 14, 2021 and September 8, 2021. Velocity data were collected by USGS staff from the Columbia Environmental Research Center at different locations in the study reach using an acoustic Doppler current profiler (ADCP) and Real Time Kinematic Global Navigation Satellite Systems (RTK GNSS) positioning. Data were used to evaluate the calibration performance of a one-dimensional hydraulic model of the WB reach. Velocity data are provided as mean velocity at distances along a stream centerline that corresponds to the one-dimensional hydraulic modeling reach in HEC-RAS. Water-surface elevation data were collected by USGS staff from the Columbia Environmental Research Center using RTK GPS for the length of the study reach. Data were used to calibrate a one-dimensional hydraulic model of the WB reach. Water surface elevations are provided at distances along a stream centerline that corresponds to the one-dimensional hydraulic modeling reach in HEC-RAS.

biota flood-regime floodplain hydrogeomorpholgy hydrology indundation little-gunpowder-falls-at-laurel-brook-maryland-usa patapsco-river-at-woodstock-maryland-usa patuxent-river-at-unity-maryland-usa seneca-creek-at-dawsonville-maryland-usa usgs-5b91250ce4b0702d0e8085bf

Terrain models representing river channel and terrestrial surface elevations were developed for use in 2D hydraulic modeling with HEC-RAS software. Channel bed elevations were determined from cross-sectional field surveys (Seneca Creek and Patapsco River) or manual corrections of the LIDAR data (Patuxent River and Little Gunpowder Falls) and integrated with the terrestrial LIDAR data.

This dataset includes 5 sets of velocity measurements and water-surface elevation measurements collected at the Lazy Day (LD) reach on the Big Piney River near St. Robert, Missouri between November 19, 2020 and August 25, 2021. Velocity data were collected by USGS staff from the Columbia Environmental Research Center at different locations in the study reach using an acoustic Doppler current profiler (ADCP) and Real Time Kinematic Global Navigation Satellite Systems (RTK GNSS) positioning. Data were used to evaluate the calibration performance of a one-dimensional hydraulic model of the LD reach. Velocity data are provided as mean velocity at distances along a stream centerline that corresponds to the one-dimensional hydraulic modeling reach in HEC-RAS. Water-surface elevation data were collected by USGS staff from the Columbia Environmental Research Center using RTK GPS for the length of the study reach. Data were used to calibrate a one-dimensional hydraulic model of the LD rea ...

Terrain models representing river channel and terrestrial surface elevations were developed for use in 2D hydraulic modeling with HEC-RAS software. Channel bed elevations were determined from cross-sectional field surveys (Seneca Creek and Patapsco River) or manual corrections of the LIDAR data (Patuxent River and Little Gunpowder Falls) and integrated with the terrestrial LIDAR data.

This U.S. Geological Survey data release consists of a polygon geospatial dataset representing estimated flood-inundation areas in Grapevine Canyon near Scotty's Castle, Death Valley National Park, and the data acquired and processed to support the delineation of those areas. Supporting datasets include topographic survey data collected by global navigation satellite system (GNSS) and terrestrial laser scanner (TLS) in Grapevine Canyon from July 12-14, 2016; derivatives of those data; pebble count data collected in Grapevine Canyon; and an archive of the one-dimensional hydraulic model used to generate the flood-inundation area polygons. Specifically: 1)a point dataset of four static reference locations (StaticGNSS_x) collected by single-baseline Online Positioning User Service – Static (OPUS-S) GNSS surveys; 2)a point dataset of 38 TLS survey scan locations (ScanOrigins_x) collected by real-time kinematic (RTK) GNSS surveys; 3)a zip file of 42 point cloud files (GrapevineCanyon_LAZ.zip) collected at 38 scan locations by TLS surveys; 4)a point dataset of 769 ground control points (GroundControlPts_x) collected by RTK GNSS surveys; 5)a point dataset of filtered ground observations (TLS_FilteredGroundObs_x) from the TLS surveys; 6)a polygon dataset of the areas used to filter the ground observations (TLS_Filter_p); 7)a digital terrain model (GrapevineCanyon_TIN.zip) derived from the filtered ground observations as a triangulated irregular network (TIN) in North American Vertical Datum of 1988; 8)a comma-separated values (CSV) table of the locations and results of five Wohlman-style pebble counts (Wolman, 1954), collected at five sites within the study area (GrapevineCanyon_PebbleCounts.csv); 9)a zip file containing all relevant files to document and run the Hydrological Engineering Center-River Analysis System (HEC-RAS) one dimensional hydraulic model used to generate the flood-inundation area polygons (SWmodel_Archive.zip); 10)a polygon dataset of the estimated flood-inundation areas (GrapevineCanyonInundationAreas_p).

The basis for these features is U.S. Geological Survey Scientific Investigation Report 2017-5024 Flood Inundation Mapping Data for Johnson Creek near Sycamore, Oregon. The domain of the HEC-RAS hydraulic model is a 12.9 mile reach of Johnson Creek from just upstream of SE 174th Avenue in Portland, Oregon to its confluence with the Willamette River. Some of the hydraulics used in the model were taken from Federal Emergency Management Agency, 2010, Flood Insurance Study, City of Portland, Oregon, Multnomah, Clackamas and Washington Counties, Volume 1 of 3, November 26, 2010. The Digital Elevation Model (DEM) utilized for the project was developed from LiDAR data flown in 2015 and provided by the Oregon Department of Geology and Mineral Industries. Bridge decks are generally removed from DEMs as standard practice. Therefore, these features may be shown as inundated when they are not. Judgement should be used when estimating the usefulness of a bridge during flood flow. Comparing the bridge to the surrounding ground can be more informative in this respect than simply looking at the bridge itself. Two model plans were used in the creation of the flood layers. The first is a stable model plan using unsteady flow in which the maximum streamflow is held in place for a long period of time (a number of days) in order to replicate a steady model using an unsteady plan. The stable model plan produced the areas of uncertainty contained in the sycor_breach.shp shapefile. The second is an unstable model plan that uses unsteady flow in which the full hydrograph (rising and falling limb) is represented based on the hydrograph shape of the December 2015 peak annual flood. The unstable model plan produced the flood extent polygons contained in the sycor.shp shapefile and the depth rasters and represents the best estimate of flood inundation for the given streamflow at U.S. Geological Survey streamgage 14211500.

The shapefiles depict the valley bottom areas over which HEC-RAS model results were summarized. Valley bottoms were manually delineated in ArcMap by visually interpreting LIDAR terrain models and aerial imagery. Substantial changes in elevation, curvature, and slope were interpreted within the context of their position within the study reach to be channel banks and valley walls. Such areas were excluded from the valley bottom delineation.

The U.S. Geological Survey (USGS), in cooperation with the Fond du Lac Band of Lake Superior Chippewa (FDLB), Minnesota, analyzed the hydrologic and hydraulic conditions within the Stoney Brook watershed. The Stoney Brook watershed covers an area of 100.8 square miles in Carlton and St. Louis counties with most of the watershed within the Fond du Lac Reservation. Wild rice, which is harvested by the FDLB, naturally grows in the lakes on the Fond du Lac Reservation and is susceptible to damage from increased water-levels after substantial rainfall events. Channel modifications and frequency rainfall events were simulated to assess lake level conditions that could mitigate potential damages to the wild rice yields. The channel modifications were also used to evaluate options for improving conveyance and floodplain storage in the watershed. The study area consists of 77.9 square miles of the watershed with the downstream boundary located 2.4 miles downstream from the USGS streamgage Stoney Brook at Pine Drive near Brookston, Minn. (USGS station 04021520; U.S. Geological Survey, 2023). A hydrologic model was used to simulate precipitation runoff and outflow hydrographs from delineated subwatersheds in the Stoney Brook watershed. A two-dimensional hydraulic model was used to simulate streamflows, volume accumulation, lake water-levels, and inundation duration and depths. The hydrologic model was developed using Hydrologic Engineering Center–Hydrologic Modeling System (HEC–HMS) computer program (version 4.3; U.S. Army Corps of Engineers, 2022) for the simulation of single rainfall events. A total of 14 subwatersheds were used in the HEC–HMS model to represent the 77.9 square mile study area within the Stoney Brook watershed. The HEC–HMS model was calibrated using streamflow time series from the USGS streamgage Stoney Brook at Pine Drive near Brookston, Minn. (USGS station 04021520; U.S. Geological Survey, 2023) to two high-flow events: April 21–30, 2008, and June 19–July 1, 2012. The calibrated HEC–HMS model used 24-hour duration design rainfall events consisting of precipitation frequencies of 1-, 2-, 5-, and 10-year recurrence intervals (100-, 50-, 20-, and 10-percent annual exceedance probabilities) for the simulation of channel modification alternatives in the hydraulic model. The hydraulic model was developed using Hydrologic Engineering Center–River Analysis System (HEC–RAS) computer program (version 6.4.1; U.S. Army Corps of Engineers, 2023). The HEC–RAS model was calibrated using streamflow time series from the USGS streamgage Stoney Brook at Pine Drive near Brookston, Minn. (USGS station 04021520; U.S. Geological Survey, 2023) to two high-flow events: April 21–30, 2008, and June 19–July 1, 2012. Channel modification alternatives were developed in the HEC–RAS model as terrain modifications and were intended to improve flow conveyances and storage and wetland coverage within the floodplain. These terrain modifications include breaches in the bank spoils, reconnecting the original channel to Stoney Brook, and clearing the original channel of soil deposition and debris. The HEC–HMS with HEC–RAS scenarios were simulated using flows from 1-, 2-, 5-, and 10-year recurrence interval (100-, 50-, 20-, and 10-percent annual exceedance probabilities) precipitation events distributed over a 24-hour duration. The HEC–RAS model was used to determine differences in hydraulic characteristics such as: peak water-surface elevations in the lakes, peak flows, volume accumulation, and inundation durations and depths. This data release contains a zip file that includes the HEC–HMS and HEC–RAS model run files, model performance and calibration metrics, and model outputs used in this study. References Cited: U.S. Army Corps of Engineers, 2018, Hydrologic Engineering Center Hydrologic Modeling System HEC–HMS 4.3. User’s Manual: U.S. Army Corps of Engineers software release, accessed October 10, 2022, at https://www.hec.usace.army.mil/software/hec-hms/downloads.aspx. U.S. Army Corps of Engineers, 2023, HEC–RAS—River analysis system version 6.4: U.S. Army Corps of Engineers software release, accessed October 2, 2023, at https://www.hec.usace.army.mil/software/hec-ras/download.aspx. U.S. Geological Survey, 2023, USGS surface-water data for the Nation, in USGS water data for the Nation: U.S. Geological Survey National Water Information System database, accessed October 2, 2023, at https://doi.org/10.5066/F7P55KJN. [Surface-water data directly accessible at https://waterdata.usgs.gov/nwis/sw.]

Within large-river ecosystems, floodplains serve a variety of important ecological functions. A recent survey of 80 managers of floodplain conservation lands along the Upper and Middle Mississippi and Lower Missouri Rivers in the central United States found that the most critical information needed to improve floodplain management centered on metrics for characterizing depth, extent, frequency, duration, and timing of inundation. These metrics can be delivered to managers efficiently through cloud-based interactive maps. To calculate these metrics, we interpolated an existing one-dimensional HEC-RAS hydraulic model for the Middle Mississippi River, which simulated water surface elevations at cross sections spaced (<1 kilometer) to sufficiently characterize water surface profiles along an approximately 800 kilometer stretch upstream from the confluence with the Mississippi River over an 80-year record at a daily time step. To translate these water surface elevations to inundation depths, we subtracted a merged terrain model consisting of floodplain LIDAR and bathymetric surveys of the river channel. We completed these calculations for an 800 kilometer stretch of the Missouri River, spanning from Rulo, Nebraska to the river's confluence with the Mississippi River. Analyzed areas include the entirety of the Mississippi River floodplain, with the exception of the St. Louis metropolitan area in which analysis was constrained to currently unleveed areas only. This approach resulted in a 29,000+ day time series of inundation depths across the floodplain using grid cells with 30 meter spatial resolution. This dataset presents 14 metrics for each of two scenarios, one using a baseline timeseries of stages from the HEC-RAS simulation and one using a timeseries of stages adjusted to account for removal of existing levees from the floodplain. These metrics are calculated on a per pixel basis and encompass a variety of temporal criteria generally relevant to flora and fauna of interest to floodplain managers, including, for example, the average number of days inundated per year within a growing season. We also include the base elevation layer that we generated to calculate depth of inundation from interpolated water-surface elevations.