Flood-inundation maps created using a synthetic rating curve for a 10-mile reach of the Sabinal River and a 7-mile reach of the West Sabinal River near Utopia, Texas, 2021

First posted February 28, 2023 For additional information, contact: Director, Oklahoma-Texas Water Science CenterU.S. Geological Survey1505 Ferguson LaneAustin, TX 78754–4501Contact Pubs Warehouse In 2021, the U.S. Survey (USGS), in cooperation with Bandera County River Authority and Groundwater District Texas Development Board, studied floods to produce a library of flood-inundation maps for Sabinal near Utopia, Texas. Digital were created 10-mile reach from USGS streamgage 08197936 below Mill Creek Vanderpool, Tex., at upstream boundary study reach, 08197970 Tex. (hereinafter referred as “Utopia gage”), downstream 7-mile West River. The depict estimates areal extent depth flooding corresponding selected gage heights (the water-surface elevation streamgage, commonly “stage”) Utopia gage. Water-surface elevations computed stream by means two-dimensional unsteady-state diffusion wave model Army Corps Engineers Hydrologic Engineering Center Analysis System program. A synthetic stage-discharge rating curve was developed using regional regression equation construct condition inputs, upper bound relation matched major flood event July 2002. hydraulic used compute 35 stages 0.5-foot (ft) increments referenced datum ranging 7 ft (near bankfull) 24 (estimated peak stage during 2002 event). These maps, conjunction real-time data gage, are intended help guide public taking individual safety precautions provide emergency management personnel tool efficiently manage operations postflood recovery efforts.