FLOOD-INUNDATION MAPS FOR A 1.6-MILE REACH OF SALT CREEK, WOOD DALE, ILLINOIS By David T. Soong, Elizabeth A. Murphy, and Jennifer B. Sharpe, 2012, U.S. Geological Survey Scientific Investigations Map 3185 ABSTRACT: Digital flood-inundation maps for a 1.6-mile reach of Salt Creek from upstream of the Chicago, Milwaukee, St. Paul & Pacific Railroad to Elizabeth Drive, Wood Dale, Illinois, were created by the U.S. Geological Survey (USGS) in cooperation with the DuPage County Stormwater Management Division. 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 of flooding corresponding to selected water levels (gage heights) at the USGS streamgage on Salt Creek at Wood Dale, Illinois (station number 05531175). Current conditions at the USGS streamgage may be obtained on the Internet at http://waterdata.usgs.gov/usa/nwis/uv?05531175. In this study, flood profiles were computed for the stream reach by means of a one-dimensional unsteady flow Full Equations (FEQ) model. The unsteady flow model was verified by comparing the rating curve output for a September 2008 flood event to discharge measurements collected at the Salt Creek at Wood Dale gage. The hydraulic model was then used to determine 14 water-surface profiles for gage heights at 0.5-ft intervals referenced to the streamgage datum and ranging from less than bankfull to approximately the highest recorded water level at the streamgage. The simulated water-surface profiles were then combined with a Geographic Information System (GIS) Digital Elevation Model (DEM) (derived from Light Detection and Ranging (LiDAR) data) in order to delineate the area flooded at each water level. The areal extent of the inundation was verified with high-water marks from a flood in July 2010 with a peak gage height of 14.08 ft recorded at the Salt Creek at Wood Dale gage. The availability of these maps along with Internet information regarding current gage height from USGS streamgages 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. DISCLAIMERS: 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 information product, for the most part, is in the public domain, it also contains copyrighted materials as noted in the text. Permission to reproduce copyrighted items for other than personal use must be secured from the copyright owner. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the display or utility of the data on any other system, or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and/or contained herein. This data base, identified as SIM 3185, has been approved for release and publication by the Director of the U.S. Geological Survey. Although this database has been subjected to rigorous review and is substantially complete,the U.S. Geological Survey reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the U.S. geological Survey nor the U.S. Government may be held liable for any damages resulting from its authorized or unauthorized use. Although the flood-inundation maps represent the boundaries of inundated areas with a distinct line, some uncertainty is associated with these maps. The flood boundaries shown were estimated based on gage heights (water-surface elevations) and streamflows at a selected USGS streamgage. Water-surface elevations along the stream reaches were estimated by hydraulic modeling, assuming unobstructed flow, and using gage height and hydrologic conditions anticipated at the USGS streamgage. The hydraulic model reflects the land-cover characteristics and any bridge, dam, levee, or other hydraulic structures existing in 2010. Unique meteorological factors (timing and distribution of precipitation) may cause actual streamflows along the modeled reach to vary from those assumed during a flood, which may lead to deviations in the water-surface elevations and inundation boundaries shown. Additional areas may be flooded due to unanticipated conditions such as: changes in the streambed elevation or roughness, backwater into major tributaries along a main stem river, or backwater from localized debris or ice jams. The accuracy of the floodwater extent portrayed on these maps will vary with the accuracy of the digital elevation model used to simulate the land surface. 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. CONTENTS: 00Readme.txt SIM3185_pamphlet.pdf SIM3185.met SIM3185_map_sheets.zip (sheets 1 through 14 in .pdf format) datafiles: This report consists of a pamphlet and 14 map sheets, each sheet has data files, and the single metadata file pertains to all of the maps. SIM3185_Shapefiles.zi--The shapefiles are as follows: Inundation_area_11.shp (.dbf/.prj/.sbn/.sbx/.shx) Inundation_area_11_5.shp (.dbf/.prj/.sbn/.sbx/.shx) Inundation_area_12.shp (.dbf/.prj/.sbn/.sbx/.shx) Inundation_area_12_5.shp (.dbf/.prj/.sbn/.sbx/.shx) Inundation_area_13.shp (.dbf/.prj/.sbn/.sbx/.shx) Inundation_area_13_5.shp (.dbf/.prj/.sbn/.sbx/.shx) Inundation_area_14.shp (.dbf/.prj/.sbn/.sbx/.shx) Inundation_area_14_5.shp (.dbf/.prj/.sbn/.sbx/.shx) Inundation_area_15.shp (.dbf/.prj/.sbn/.sbx/.shx) Inundation_area_15_5.shp (.dbf/.prj/.sbn/.sbx/.shx) Inundation_area_16.shp (.dbf/.prj/.sbn/.sbx/.shx) Inundation_area_16_5.shp (.dbf/.prj/.sbn/.sbx/.shx) Inundation_area_17.shp (.dbf/.prj/.sbn/.sbx/.shx) Inundation_area_17_5.shp (.dbf/.prj/.sbn/.sbx/.shx) grids.zip --The grids are as follows: salt_cr11 salt_cr11_5 salt_cr12 salt_cr12_5 salt_cr13 salt_cr13_5 salt_cr14 salt_cr14_5 salt_cr15 salt_cr15_5 salt_cr16 salt_cr16_5 salt_cr17 salt_cr17_5 SIM3185_kmz_files (folder) SIM3185_kmz.zip VI. INSTRUCTIONS AND DOCUMENTATION FOR U.S. GEOLOGICAL SURVEY SCIENTIFIC INVESTIGATIONS MAP 3185 To access the data: The data files can be downloaded via the web from http://pubs.usgs.gov/sim/3185.The main product is a Portable Document Format (.pdf) map and pamphlet which requires Adobe Acrobat for viewing. Acrobat softwareruns on a variety of systems, and is available for download free of charge from Adobe at http://www.adobe.com. To access the .kmz files in this report, download and install Google Earth free of charge at http://www.google.com/earth/index.htm. Launch Google Earth, click the file menu and choose open. Locate and select the .kmz file on your computer. References to non-U.S. Department of the Interior (DOI) products do not constitute an endorsement by the DOI. By viewing the Google Maps API on this web site the user agrees to these terms(terms found at: http://code.google.com/apis/maps/terms.html) of Service set forth by Google. Software Recommended: Adobe Acrobat (6.x, 7.x, or 8.x), or Adobe Acrobat Pro (6.x, 7.x, or 8.x), or the free Adobe Reader (6.x, 7.x, or 8.x), 8.x is preferred.ArcGIS 9.3 preferred, older versions may also work.