Fort Morgan Flood Inundation Mapping Study Completed
In 2017, the U.S. Geological Survey (USGS), in cooperation with the Colorado Water Conservation Board (CWCB), studied floods in the historic record to produce a library of flood-inundation maps for the South Platte River at Fort Morgan, Colorado.
Digital Flood-inundation Maps
Digital flood-inundation maps for a 4.5-mile (7.2-kilometers) reach of the South Platte River at Fort Morgan from Morgan County Road 16 to Morgan County Road 20.5, were created.
The flood-inundation maps depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the U.S. Geological Survey streamgage on the South Platte River at Fort Morgan (streamgage number 06759500).
Water-surface 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.
Water-surface 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 simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from light detection and ranging data having a 0.37-ft [0.11-m] vertical accuracy and 3.28-ft [1.00-m] horizontal resolution) to delineate the area flooded for stages ranging from 12 to 27 ft (3.66 to 8.23 m).
These flood-inundation maps, in conjunction with the real-time stage data from the USGS streamgage on the South Platte River at Fort Morgan, are intended to help guide the general public in taking individual safety precautions and provide emergency management personnel with a tool to efficiently manage emergency flood operations and post flood recovery efforts.
OBJECTIVES:
- Compile historic flood data from the Fort Morgan streamgage
- Collect additional stage data by deploying pressure transducers throughout the study area
- Collect and compile topographic and bathymetric data for selected cross sections and geometric data for structures and bridges along the study area
- Estimate energy-loss factors (roughness coefficients) in the stream channel and flood plain and determination of steady-flow data
- Compute water-surface profiles using the U.S. Army Corps of Engineers Hydrologic Engineering Center River Analysis System computer program
- Produce estimated flood-inundation maps at various stages using the U.S. Army Corps of Engineers Hydrologic Engineering Center GeoRiver Analysis System computer program
- Prepare flood-inundation maps, both as shapefile polygons that depict the areal extent of flood inundation and as depth grids that provide the depth of floodwaters, for display on a USGS flood-inundation mapping application.
Below are other science projects associated with this project.
Flood Database for Colorado
Below are data or web applications associated with this project.
Geospatial Data and Surface-Water Model Archive for a Flood-Inundation Mapping Study of the South Platte River at Fort Morgan, Colorado, 2018
Cross Section Data and Pressure Transducer Location of the South Platter River near Fort Morgan, Colorado, 2017
Below are data or web applications associated with this project.
Flood Inundation Mapper
USGS Flood Inundation Maps, along with Internet information regarding current stage from the USGS streamgage, provide 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.
Flood Database for Colorado
An easy-to-use, Web-based geodatabase of historical flood and paleoflood information which includes links to sources of flood data. The interface makes this collection of information useful to water-resource managers to better understand the historic events for improved flood-frequency estimates of the largest floods in Colorado.
Below are partners associated with this project.
- Overview
In 2017, the U.S. Geological Survey (USGS), in cooperation with the Colorado Water Conservation Board (CWCB), studied floods in the historic record to produce a library of flood-inundation maps for the South Platte River at Fort Morgan, Colorado.
Digital Flood-inundation Maps
Digital flood-inundation maps for a 4.5-mile (7.2-kilometers) reach of the South Platte River at Fort Morgan from Morgan County Road 16 to Morgan County Road 20.5, were created.
The flood-inundation maps depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the U.S. Geological Survey streamgage on the South Platte River at Fort Morgan (streamgage number 06759500).
Water-surface 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.
Water-surface 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 simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from light detection and ranging data having a 0.37-ft [0.11-m] vertical accuracy and 3.28-ft [1.00-m] horizontal resolution) to delineate the area flooded for stages ranging from 12 to 27 ft (3.66 to 8.23 m).
These flood-inundation maps, in conjunction with the real-time stage data from the USGS streamgage on the South Platte River at Fort Morgan, are intended to help guide the general public in taking individual safety precautions and provide emergency management personnel with a tool to efficiently manage emergency flood operations and post flood recovery efforts.
OBJECTIVES:
- Compile historic flood data from the Fort Morgan streamgage
- Collect additional stage data by deploying pressure transducers throughout the study area
- Collect and compile topographic and bathymetric data for selected cross sections and geometric data for structures and bridges along the study area
- Estimate energy-loss factors (roughness coefficients) in the stream channel and flood plain and determination of steady-flow data
- Compute water-surface profiles using the U.S. Army Corps of Engineers Hydrologic Engineering Center River Analysis System computer program
- Produce estimated flood-inundation maps at various stages using the U.S. Army Corps of Engineers Hydrologic Engineering Center GeoRiver Analysis System computer program
- Prepare flood-inundation maps, both as shapefile polygons that depict the areal extent of flood inundation and as depth grids that provide the depth of floodwaters, for display on a USGS flood-inundation mapping application.
- Science
Below are other science projects associated with this project.
Flood Database for Colorado
The U.S. Geological Survey, in cooperation with the Colorado Department of Transportation, created a Web-based geodatabase for information on floods from 1867 through water year 2015 and information on paleofloods occurring in the past 5,000 to 10,000 years. The geodatabase was created using Environmental Systems Research Institute ArcGIS JavaScript Application Programing Interface. Engineers... - Data
Below are data or web applications associated with this project.
Geospatial Data and Surface-Water Model Archive for a Flood-Inundation Mapping Study of the South Platte River at Fort Morgan, Colorado, 2018
The development and the generation of the datasets that are published through this data release, were based on the results and findings of this 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 dataseCross Section Data and Pressure Transducer Location of the South Platter River near Fort Morgan, Colorado, 2017
The USGS Colorado Water Science Center, in cooperation with the Colorado Water Conservation Board, collected hydraulic data for the South Platte River for areas adjacent to Fort Morgan, Colo., based on the USGS streamgage 06759500 South Platte River at Fort Morgan, CO. The hydraulic data include survey point data for 54 cross sections and 10 pressure transducers, which are used to record the river - Web Tools
Below are data or web applications associated with this project.
Flood Inundation Mapper
USGS Flood Inundation Maps, along with Internet information regarding current stage from the USGS streamgage, provide 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.
Flood Database for Colorado
An easy-to-use, Web-based geodatabase of historical flood and paleoflood information which includes links to sources of flood data. The interface makes this collection of information useful to water-resource managers to better understand the historic events for improved flood-frequency estimates of the largest floods in Colorado.
- Partners
Below are partners associated with this project.