sfpc_6_0

Raster Dataset

Tags
South Fork Peachtree Creek, DeKalb County, Clarkston, high-water marks, flooded area, flood, Georgia, geospatial analysis, river/stream, flood-inundation maps


Summary

This dataset was created to support the development of flood-peak inundation maps for South Fork Peachtree Creek in DeKalb County, Georgia

Description

Digital flood-inundation maps for a 5.3-mile reach of South Fork Peachtree Creek from the Brockett Road bridge to the Willivee Driver bridge, DeKalb County, Georgia, were created by the USGS in cooperation with the cities of DeKalb County, Georiga. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage South Fork Peachtree at Casa Drive, near Clarkston, Georgia (02336152). Current conditions at the USGS streamgage may be obtained on the Internet. In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http:/water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often collocated at USGS streamgages. The forecasted peak-stage information, also available on the Internet, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated using the most current stage-discharge relations at the South Fork Peachtree at Casa Drive, near Clarkston (02336152) streamgage and documented high-water marks from recent floods. The hydraulic model was then used to determine 13 water-surface profiles for flood stages at 0.5-foot intervals referenced to the streamgage datum and ranging from bankfull (6.0 feet) to approximately 3.21 feet above the highest recorded water level at the streamgage. The flood-peak inundation area was modeled in a GIS by combining steady-state hydraulic modeling and available lidar digital elevation model (DEM) data. Information about the study, floods, and methods used can be found in the USGS Scientific Investigations Map 3347. https://dx.doi.org/10.3133/sim3347

Credits

Use limitations

Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of this data, software, or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. The flood boundaries shown were estimated based on water stages/streamflows at the USGS streamflow-gaging station South Fork Peachtree at Casa Drive, near Clarkston, Georgia (02336152), steady-state hydraulic modeling (assuming unobstructed flow), and a digital elevation model. The hydraulic model reflects the land-cover characteristics and any bridge, dam, levee, or other hydraulic structures existing on July, 2015. Unique meteorological factors (timing and distribution of storm) could cause actual streamflows along the modeled reach to vary from those assumed during a flood, which may lead to deviations from the water surface elevations and inundation boundaries shown here. Additional areas may be flooded due to unanticipated backwater from major tributaries along the main stem or from localized debris- or ice-jams. Inundated areas shown should not be used for navigation, regulatory, permitting, or other legal purposes. Although USGS intends to make this server available 24 hours a day, seven days a week, timely delivery of data and products from this server through the Internet is not guaranteed. The USGS provides these maps "as-is" for a quick reference, emergency planning tool but assumes no legal liability, or responsibility resulting from the use of this information. If this series of flood inundation maps will be used in conjunction with National Weather Service (NWS) river forecasts, the user should be aware of additional uncertainties which may be inherent or factored into NWS forecast procedures. The NWS uses river forecast models to estimate the quantity and timing of water flowing through selected river reaches in the United States. These forecast models (1) estimate the amount of runoff generated by a precipitation event, (2) compute how the water will move downstream, and (3) predict the flow and stage (water surface elevation) for the river at a given location (AHPS forecast point) throughout the forecast period (every six hours and 3 to 5 days out in many locations). For more information on AHPS forecasts, please see: http://water.weather.gov/ahps/pcpn_and_river_forecasting.pdf .

Extent

West -84.303037   East -84.231334
North 33.825489   South 33.802414

Scale Range
Maximum (zoomed in) 1:5,000
Minimum (zoomed out) 1:150,000,000

ArcGIS Metadata 

Topics and Keywords 

Themes or categories of the resource  elevation, environment, inlandWaters


*Content type  Downloadable Data
Export to FGDC CSDGM XML format as Resource Description No

Place keywords  South Fork Peachtree Creek, DeKalb County, Clarkston, Georgia

Theme keywords  high-water marks, flooded area, flood, geospatial analysis, river/stream, flood-inundation maps

Citation 

*Title sfpc_6_0
Publication date 2015-07-30 00:00:00


Presentation formats  digital map


Series
Name SIM
Issue 3347

Collection title Flood-Inundation Maps for South Fork Peachtree Creek from the Brockett Road Bridge to the Willivee Drive Bridge, DeKalb County, Georgia


Citation Contacts 

Responsible party
Organization's name U.S. Geological Survey, South Atlantic Water Science Center
Contact's role  originator


Responsible party
Organization's name U.S. Geological Survey
Contact's role  publisher


Contact information
Address
Delivery point Reston, Virginia



Resource Details 

Dataset languages  English (UNITED STATES)
Dataset character set  utf8 - 8 bit UCS Transfer Format


Status  completed
Spatial representation type* grid


Supplemental information
A GIS application was used to produce a plane representing the flood-peak water surface. The application duplicates the water-surface-elevation data from cross-section points across the flood plain perpendicular to the direction of the flood flow. Elevations between water-surface points on the cross-sections are proportional interpolations of the water-surface-elevation data and were positioned to generate a flood surface sloping with the water flow. A raster surface was created with the data points using a spline interpolation method, forming the estimated flood surface. A flood-depth grid was made by subtracting the DEM from the flood surface. The flood-peak inundation areas are available in a GIS format, polyline shapefile, that provides extent of the flood peak for each stage level. This format allows the GIS data to be overlain on maps and aerial photographs, and to be used for various GIS applications, such as FEMA's Hazards U.S. Multi-Hazards (HAZUS-MH) program (Federal Emergency Management Agency, 2010b) to estimate flood damages. For more information on data processing and checking procedures, see the full report at https://dx.doi.org/10.3133/sim3347 Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this Federal Geographic Data Committee-compliant metadata file is intended to document the dataset in nonproprietary form, as well as in ArcGIS format, this metadata file may include some ArcGIS-specific terminology.

*Processing environment Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.2.2.3552


ArcGIS item properties
*Name sfpc_6_0
*Location file://E:\SFPeachtree\publish\depth_grids\sfpc_6_0
*Access protocol Local Area Network

Extents 

Extent
Description
ground condition

Geographic extent
Bounding rectangle
Extent type  Extent used for searching
*West longitude -84.303037
*East longitude -84.231334
*North latitude 33.825489
*South latitude 33.802414
*Extent contains the resource Yes

Temporal extent
Date and time 2015-10-01 00:00:00

Extent in the item's coordinate system
*West longitude 2255169.500000
*East longitude 2276939.500000
*South latitude 1383192.500000
*North latitude 1391567.500000
*Extent contains the resource Yes

Resource Points of Contact 

Point of contact
Organization's name US Geological Survey, South Atlantic Water Science Center
Contact's role  point of contact


Contact information
Phone
Voice 678-924-6700

Address
Type both
Delivery point 1770 Corporate Drive, Suite 500
City Norcross
Administrative area Georgia
Postal code 30093
Country US



Resource Maintenance 

Resource maintenance
Update frequency  not planned


Resource Constraints 

Legal constraints
Limitations of use
Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of this data, software, or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. This coverage may be reistributed if it is not edited and is properly referenced. The flood boundaries shown were estimated based on water stages/streamflows at the USGS streamflow-gaging station South Fork Peachtree at Casa Drive, near Clarkston, Georgia (02336152), steady-state hydraulic modeling (assuming unobstructed flow), and a digital elevation model. The hydraulic model reflects the land-cover characteristics and any bridge, dam, levee, or other hydraulic structures existing on July 2015. Unique meteorological factors (timing and distribution of storm) could cause actual streamflows along the modeled reach to vary from those assumed during a flood, which may lead to deviations from the water surface elevations and inundation boundaries shown here. Additional areas may be flooded due to unanticipated backwater from major tributaries along the main stem or from localized debris- or ice-jams. Inundated areas shown should not be used for navigation, regulatory, permitting, or other legal purposes. Although USGS intends to make this server available 24 hours a day, seven days a week, timely delivery of data and products from this server through the Internet is not guaranteed. The USGS provides these maps "as-is" for a quick reference, emergency planning tool but assumes no legal liability, or responsibility resulting from the use of this information. If this series of flood inundation maps will be used in conjunction with National Weather Service (NWS) river forecasts, the user should be aware of additional uncertainties which may be inherent or factored into NWS forecast procedures. The NWS uses river forecast models to estimate the quantity and timing of water flowing through selected river reaches in the United States. These forecast models (1) estimate the amount of runoff generated by a precipitation event, (2) compute how the water will move downstream, and (3) predict the flow and stage (water surface elevation) for the river at a given location (AHPS forecast point) throughout the forecast period (every six hours and 3 to 5 days out in many locations). For more information on AHPS forecasts, please see: http://water.weather.gov/ahps/pcpn_and_river_forecasting.pdf .

Other constraints
None. This dataset is provided by USGS as a public service.

Constraints
Limitations of use

Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of this data, software, or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. The flood boundaries shown were estimated based on water stages/streamflows at the USGS streamflow-gaging station South Fork Peachtree at Casa Drive, near Clarkston, Georgia (02336152), steady-state hydraulic modeling (assuming unobstructed flow), and a digital elevation model. The hydraulic model reflects the land-cover characteristics and any bridge, dam, levee, or other hydraulic structures existing on July, 2015. Unique meteorological factors (timing and distribution of storm) could cause actual streamflows along the modeled reach to vary from those assumed during a flood, which may lead to deviations from the water surface elevations and inundation boundaries shown here. Additional areas may be flooded due to unanticipated backwater from major tributaries along the main stem or from localized debris- or ice-jams. Inundated areas shown should not be used for navigation, regulatory, permitting, or other legal purposes. Although USGS intends to make this server available 24 hours a day, seven days a week, timely delivery of data and products from this server through the Internet is not guaranteed. The USGS provides these maps "as-is" for a quick reference, emergency planning tool but assumes no legal liability, or responsibility resulting from the use of this information. If this series of flood inundation maps will be used in conjunction with National Weather Service (NWS) river forecasts, the user should be aware of additional uncertainties which may be inherent or factored into NWS forecast procedures. The NWS uses river forecast models to estimate the quantity and timing of water flowing through selected river reaches in the United States. These forecast models (1) estimate the amount of runoff generated by a precipitation event, (2) compute how the water will move downstream, and (3) predict the flow and stage (water surface elevation) for the river at a given location (AHPS forecast point) throughout the forecast period (every six hours and 3 to 5 days out in many locations). For more information on AHPS forecasts, please see: http://water.weather.gov/ahps/pcpn_and_river_forecasting.pdf .


Spatial Reference 

ArcGIS coordinate system
*Type Projected
*Geographic coordinate reference GCS_North_American_1983
*Projection NAD_1983_StatePlane_Georgia_West_FIPS_1002_Feet
*Coordinate reference details
Projected coordinate system
Well-known identifier 102667
X origin -16150100
Y origin -43703500
XY scale 137255279.03396165
Z origin -100000
Z scale 10000
M origin -100000
M scale 10000
XY tolerance 0.0032808333333333331
Z tolerance 0.001
M tolerance 0.001
High precision true
Latest well-known identifier 2240
Well-known text PROJCS["NAD_1983_StatePlane_Georgia_West_FIPS_1002_Feet",GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",2296583.333333333],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",-84.16666666666667],PARAMETER["Scale_Factor",0.9999],PARAMETER["Latitude_Of_Origin",30.0],UNIT["Foot_US",0.3048006096012192],AUTHORITY["EPSG",2240]]

Reference system identifier
*Value 2240
*Codespace EPSG
*Version 8.2.6


Spatial Data Properties 

Georectified Grid
*Number of dimensions 2


Axis dimensions properties
Dimension type  column (x-axis)
*Dimension size 4354
*Resolution  5.000000 Foot_US

Axis dimensions properties
Dimension type  row (y-axis)
*Dimension size 1675
*Resolution  5.000000 Foot_US

*Cell geometry  area
*Point in pixel  center


*Transformation parameters are available Yes


*Check points are available No


Corner points
*Point 2255169.500000 1383192.500000
*Point 2255169.500000 1391567.500000
*Point 2276939.500000 1391567.500000
*Point 2276939.500000 1383192.500000

*Center point 2266054.500000 1387380.000000




ArcGIS Raster Properties
General Information
*Pixel depth 32
*Compression type RLE
*Number of bands 1
*Raster format GRID
*Source type continuous
*Pixel type floating point
*No data value -3.4028235e+038
*Has colormap No
*Has pyramids No




Spatial Data Content 

Image Description
*Type of information  physical measurement
Attribute described by cell values Depth of water


Band information
*Description sfpc_6_0
Sequence identifier
Name 1


*Maximum value 6.600000
*Minimum value 0.000000
Units
Symbol [ft_us]

*Number of bits per value 32


Triangulation has been performed No
Radiometric calibration is available No
Camera calibration is available No
Film distortion information is available No
Lens distortion information is available No


Data Quality 

Scope of quality information


Data quality report - Completeness omission
Measure description
This dataset is complete; there are no planned revisions or updates at this time.





Data quality report - Absolute external positional accuracy
Dimension horizontal


Measure description
Used cross-section data points from surveyed data, accurate to the datum of the survey. Flood inundation extent was manually checked by sampling the digital elevation model (DEM) adjacent to high water marks. This check was done to verify that DEM elevations greater than the high-water mark were not in the flood inundation polygon and elevations less than the high water mark were within the flood inundation polygon.



Evaluation method
n/a





Data quality report - Absolute external positional accuracy
Dimension vertical


Measure description
Used cross-section data points from surveyed data, accurate to the datum of the survey. Flood inundation extent was manually checked by sampling the digital elevation model (DEM) adjacent to high water marks. This check was done to verify that DEM elevations greater than the high-water mark were not in the flood inundation polygon and elevations less than the high water mark were within the flood inundation polygon.Vertical accuracy to the input Lidar DEM dataset.



Evaluation method
n/a





Lineage 

Process step
When the process occurred 2015-07-30 00:00:00
Description
A GIS application was used to produce a plane representing the flood-peak water surface. The application duplicates the water-surface-elevation data from cross-section points of the hydraulic model across the flood plain perpendicular to the direction of the flood flow. Elevations between water-surface points on the cross-sections are proportional interpolations of the water-surface-elevation data and were positioned to generate a flood surface sloping with the water flow. A raster surface was created with the data points using a spline interpolation method, forming the estimated flood surface. A flood-depth grid was made by subtracting the DEM from the flood surface raster.





Source data
Description
Numeric hydraulic model was used to compute water surface profiles at selected elevations along mapped reach. The water surface profiles were then used to generate the inundation map boundaries.



Resolution of the source data
Scale denominator 1

Extent of the source data
Description
ground condition



Geoprocessing history 

Process
Process name
Date 2015-08-28 09:59:04
Tool location d:\arcgis\desktop10.2\ArcToolbox\Toolboxes\Spatial Analyst Tools.tbx\ExtractByMask
Command issued
ExtractByMask sfpc_6_0 E:\SFPeachtree\publish\inundation_layers\sfpc_6_0.shp E:\SFPeachtree\publish\depth_grids\sfpc_6_0
Include in lineage when exporting metadata No


Distribution 

Distributor
Contact information
Organization's name US Geological Survey, South Atlantic Water Science Center
Contact's role  distributor


Contact information
Phone
Voice 678-924-6700

Address
Type both
Delivery point 1770 Corporate Drive
City Norcross
Administrative area GA
Postal code 30093
Country US



Available format
Name Arc GRID file
Version 1
Technical prerequisites Data are supplied in ArcINFO format. Format compatibility is the user's responsibility.


Ordering process
Terms and fees none
Instructions
none


Transfer options
Online source
Locationhttp://water.usgs.gov/osw/flood_inundation/

Transfer options
Medium of distribution
Medium name  CD-ROM


How data is written  iso9660 (CD-ROM)




Distribution format
*Name Raster Dataset


Transfer options
Online source
Locationhttps://dx.doi.org/10.3133/sim3347

Fields 

Details for object  01391500
 
Type Feature Class
Row count 11
Definition
depth of flood inundation

Definition source
U.S. Geological Survey



Overview Description
Entity and Attribute Overview
Each entity corresponds to an estimated flood extent area for stream stages 6.0-12.0 feet at the USGS streamgage 02336152. South Fork Peachtree Creek at Casa Drive, near Clarkston, Georgia. [The attributes represent the depth range that correlates with the stage.]



Entity and Attribute Detail Citation
Musser, J.W., 2015, Flood-inundation maps for South Fork Peachtree Creek from the Brockett Road bridge to the Willivee Drive bridge, DeKalb County, Georgia: U.S. Geological Survey Scientific Investigations Map 3347, 10-p. pamphlet, 13 sheets, https://dx.doi.org/10.3133/sim3347.





References 

Aggregate Information
Association type  larger work citation


Aggregate resource name
Title Flood-inundation maps for South Fork Peachtree Creek from the Brockett Road bridge to the Willivee Drive bridge, DeKalb County, Georgia
Publication date 2015-07-30 00:00:00


Presentation formats  digital document
FGDC geospatial presentation format  document


Series
Name Scientific Investigations Map
Issue 3347

Other citation details
Musser, J.W., 2015, Flood-inundation maps for South Fork Peachtree Creek from the Brockett Road bridge to the Willivee Drive bridge, DeKalb County, Georgia: U.S. Geological Survey Scientific Investigations Map 3347, 10-p. pamphlet, 13 sheets, https://dx.doi.org/10.3133/sim3347.



Responsible party
Organization's name US Geological Survey, South Atlantic Water Science Center
Contact's role  originator


Resource location online
Locationhttps://dx.doi.org/10.3133/sim3347



Metadata Details 

Metadata language English (UNITED STATES)
Metadata character set  utf8 - 8 bit UCS Transfer Format


Scope of the data described by the metadata  dataset
Scope name* dataset


*Last update 2015-10-13


ArcGIS metadata properties
Metadata format ArcGIS 1.0
Metadata style FGDC CSDGM Metadata
Standard or profile used to edit metadata FGDC


Created in ArcGIS for the item 2015-08-28 09:59:04
Last modified in ArcGIS for the item 2015-10-13 16:59:32


Automatic updates
Have been performed Yes
Last update 2015-10-13 16:59:32


Metadata Contacts 

Metadata contact
Organization's name US Geological Survey
Contact's position Ask USGS - Water Webserver Team
Contact's role  point of contact


Contact information
Phone
Voice 1-888-275-8747 (1-888-ASK-USGS)

Address
Type postal
Delivery point 507 National Center
City Reston
Administrative area Virginia
Postal code 20192
Country US



Metadata Maintenance 

Maintenance
Update frequency  not planned


Other maintenance requirements
Last metadata review date: 2015-08-07



FGDC Metadata (read-only) 

Entities and Attributes