U.S. Geological Survey
201601
U.S. Geological Survey
Reston, Virginia
http://dx.doi.org/10.3133/sir20155190
01350000vector digital dataUS Geological Survey, New York Water Science CenterFlood-Inundation Maps for the Schoharie Creek at Prattsville, New York, 2014documentScientific Investigations Report2015-5190http://dx.doi.org/10.3133/sir20155190201601Nystrom, E.A., 2016, Flood-inundation maps for the Schoharie Creek at Prattsville, New York, 2014: U.S. Geological Survey Scientific Investigations Report 2015-5190, 12 p., 17 sheets, http://dx.doi.org/10.3133/sir20155190.Reston, VirginiaU.S. Geological Surveyhttp://dx.doi.org/10.3133/sir20155190SIR2015-5190http://wimcloud.usgs.gov/apps/FIM/FloodInundationMapper.htmlFlood-Inundation Maps for the Schoharie Creek at Prattsville, New York, 2014
Digital flood-inundation maps for a 2.6-mile reach of the Schoharie Creek in Prattsville, New York, from the confluence of Schoharie Creek and the Batavia Kill to approximately 0.5 mile upstream of Schoharie Reservoir, were created by the U.S. Geological Survey (USGS) in cooperation with the New York Department of Environmental Conservation. The flood-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 on the Schoharie Creek at Prattsville, NY (station number 01350000). Near-real-time stages at this streamgage may be obtained on the Internet from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service at http:/water.weather.gov/ahps/, which also forecasts flood hydrographs at this site.
Flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated by using the current stage-discharge relations at the Schoharie Creek at Prattsville, NY (station number 01350000) streamgage and high-water marks from the flood of August 28, 2011. The hydraulic model was then used to computer 17 water-surface profiles for flood stages at 1-foot (ft) intervals referenced to the streamgage datum and ranging from 9 ft, or action stage, to 25 ft, approximately the highest recorded water level at the streamgage. The simulated water-surface profiles were then combined with a geographic information system digital elevation model (derived from light detection and ranging [lidar] data having a vertical 0.61-ft root mean squared error and 6.6-ft horizontal resolution) to delineate the area flooded at each water level.
Information about the study, floods, and methods used can be found in the USGS Scientific Investigations Report 2015-5190. http://dx.doi.org/10.3133/sir20155190
The availability of these maps, along with Internet information regarding current stage from the USGS streamgage and forecasted high-flow stages from the NWS will 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.
enA hydraulic model and GIS application were used to produce 17 water-surface elevation profiles. The application models the water-surface elevation across the flood-plain perpendicular to the direction of flow. Flood-depth grids were made by subtracting a DEM from the water surface elevation profiles. The inundation areas are available in a GIS shapefile format that provides the 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 (http://www.fema.gov/hazus) to estimate flood damages. For more information on data processing and checking procedures, see the full report at http://dx.doi.org/10.3133/sir20155190
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.
2015
ground condition
None planned
-74.442124
-74.416779
42.333689
42.303102
PrattsvilleNew YorkSchoharie Creeknone
floodriverstreamflood-inundation mapshigh-water marksflooded areageospatial analysisnone
None. This dataset is provided by the U.S. Geological Survey (USGS) as a public service.
mailing and physical address425 Jordan RdTroyNY12180(518) 285-5600US Geological Survey, New York Water Science CenterMicrosoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.1.1.3143UnclassifiedShapefile
Attributes for water-surface elevations were input from the HEC-RAS model output data table. Flow input data for the HEC-RAS model were obtained from the most current stage-discharge relation at the USGS streamgage 01350000 Schoharie Creek at Prattsville, NY.
This dataset is complete, but revisions or updates may be made following the planned replacement of the State Route 23 bridge over the Schoharie Creek.
Used cross-section data points from surveyed data, accurate to the datum of the survey.
Used cross-section data points from surveyed data, accurate to the datum of the survey. Vertical accuracy of the input lidar DEM dataset was 0.61 ft root mean squared error (RMSE).
U.S. Geological Survey, New York Water Science CenterFlood-Inundation Maps for the Schoharie Creek at Prattsville, New York, 2014201X
201410
ground condition
Hydraulic modelNumeric hydraulic modelNumeric 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.
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.
Vector
String
17
SimplePolylineFALSE17FALSEFALSE
NAD 1983 UTM Zone 18N
0.9996
-75.0
0.0
500000.0
0.0
coordinate pair
0.000000002220024164500956
0.000000002220024164500956
meter
D North American 1983
GRS 1980
6378137.0
298.257222101
North American Vertical Datum of 1988feetAttribute values
Flood-inundation polygons for station ID 01350000Feature Class1101350000 flood-inundation areaU.S. Geological Survey
FIDFIDOID400Internal feature number.ESRIShapeShapeGeometry000Feature geometry.ESRICoordinates defining the features.STAGESTAGEFloat19USGS stage height associated with the area, in feet.U.S. Geological Survey11ELEVELEVFloat19NAVD88 elevation that correlates with the stage, in feet.U.S. Geological Survey11USGSIDUSGSIDString50USGS station ID numberU.S. Geological Survey
UNCERTAINTIES AND LIMITATIONS REGARDING USE OF FLOOD-INUNDATION MAPS
The flood boundaries shown were estimated based on water stages/streamflows at the USGS streamflow-gaging station 01350000, Schoharie Creek at Prattsville, 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 in October 2014. 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, 7 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 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 6 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.Each entity corresponds to an estimated flood-extent area for stream stages 9-25 feet at the USGS streamgage 01350000, Schoharie Creek at Prattsville New York. The attributes represent the USGS station ID, USGS stage height associated with the area, and NAVD 88 elevation that correlates with the stage.Nystrom, E.A., 2016, Flood-inundation maps for the Schoharie Creek at Prattsville, New York: U.S. Geological Survey Scientific Investigations Report 2015-5190, 12 p., 17 sheets, http://dx.doi.org/10.3133/sir20155190.
mailing and physical address
425 Jordan Rd
Troy
NY
12180
(518) 285-5600
US Geological Survey, New York Water Science Center
Although these data have been used by the USGS, U.S. Department of the Interior, no warranty expressed or implied is made by the USGS as to the accuracy of the data. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these 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 redistributed 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 01350000 Schoharie Creek at Prattsville, NY, 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 in October 2014. 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, 7 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 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 6 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 .
shapefile
http://water.usgs.gov/osw/flood_inundation/
none
none
Downloadable DataData are supplied in ArcGIS shapefile format. Format compatibility is the user's responsibility.
20150410
mailing address
507 National CenterRestonVirginia20192USA
1-888-275-8747 (1-888-ASK-USGS)Ask USGS - Water Webserver TeamUS Geological Survey
FGDC Content Standards for Digital Geospatial Metadata
FGDC-STD-001-1998
local time
en201601