Geospatial and model dataset for flood-Inundation maps in a 10-mile reach of the Sabinal River and a 7-mile reach of the West Sabinal River near Utopia, Texas, 2021

This data release documents the digital data used to produce flood-inundation maps for a range of gage heights (stages) for the Sabinal River near Utopia, Tex. The simulated flood-inundation maps correspond to a range in stage from 11 to 28 feet (ft) at U.S. Geological Survey (USGS) streamgage 08197970 Sabinal River at Utopia, Tex. at intervals of 0.5-ft. The maps were created for a 10-mile reach of the Sabinal River extending from USGS streamgage 08197936 Sabinal River below Mill Creek near Vanderpool, Tex. to USGS streamgage 08197970 Sabinal River at Utopia, Tex. (hereinafter referred to as the “Utopia gage”) and 7-mile reach of the West Sabinal River were created by the USGS in cooperation with the Bandera County River Authority and Groundwater District and with the Texas Water Development Board. Stage data are collected every 5 minutes and used for estimating areas of inundation near the Utopia gage; the stage data are available from the USGS National Water Information System (NWIS) online database at https://dx.doi.org/10.5066/F7P55KJN (gage information are also directly accessible at https://waterdata.usgs.gov/nwis/). The companion interpretive report (larger work citation) accompanying these digital data is Choi, N., 2023, 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 (ver 2.0, September 2023): U.S. Geological Survey Scientific Investigations Report 2023-5001, 18 p., https://doi.org/10.3133/sir20235001.
Flood profiles were computed for the stream reach by means of a two-dimensional unsteady state diffusion wave model, Hydrologic Engineering Center's River Analysis System (HEC–RAS; Davidian, 1984; U.S. Army Corps of Engineers, 2016a, b, c). The model results were validated using a synthetic stage-discharge relation at the Utopia gage; the synthetic rating curve was developed based on a regional regression equation by Asquith and others (2013). Detailed information about the methods and data used for this analysis are provided in the companion interpretive report. The flood-inundation maps can be accessed through the Interagency Flood Risk Management Flood Decision Support Toolbox website at https://webapps.usgs.gov/infrm/fdst/.

本数据集发布内容涵盖了用于生成美国得克萨斯州尤托皮亚（Utopia）附近萨宾纳尔河（Sabinal River）各水位对应的洪水淹没地图的数字数据。所模拟的洪水淹没地图对应美国地质调查局（U.S. Geological Survey，简称USGS）编号08197970的尤托皮亚萨宾纳尔河水位站11至28英尺（ft）的水位区间，步长为0.5英尺。本次制作的淹没地图覆盖两段河道：一段为萨宾纳尔河10英里河段，范围从得克萨斯州范德普尔附近米尔克里克下游的USGS编号08197936水位站至前述的尤托皮亚USGS编号08197970水位站（以下简称“尤托皮亚水位站”）；另一段为西萨宾纳尔河7英里河段。本数据集由美国地质调查局联合班德拉县河流管理局与地下水管理区、得克萨斯州水资源开发委员会共同编制。尤托皮亚水位站的水位数据每5分钟采集一次，用于估算该站附近的淹没区域；此类水位数据可通过美国地质调查局国家水信息系统（National Water Information System，简称NWIS）在线数据库获取，链接为https://dx.doi.org/10.5066/F7P55KJN（水位站信息也可直接通过https://waterdata.usgs.gov/nwis/访问）。随本数字数据集附带的配套解读报告（完整文献引用信息）为：Choi, N.，2023年，《基于综合水位流量关系曲线生成的得克萨斯州尤托皮亚附近萨宾纳尔河10英里河段与西萨宾纳尔河7英里河段洪水淹没地图（2021版，2.0版，2023年9月）》：美国地质调查局科学调查报告2023-5001，共18页，链接为https://doi.org/10.3133/sir20235001。研究河段的洪水演进剖面通过二维非恒定扩散波模型——水文工程中心河流分析系统（Hydrologic Engineering Center's River Analysis System，简称HEC-RAS；Davidian，1984；美国陆军工程兵团，2016a、b、c）——计算得到。模型结果通过尤托皮亚水位站的综合水位流量关系进行了验证；该综合水位流量关系曲线是基于Asquith等人（2013）提出的区域回归方程构建的。本次分析所采用的方法与数据的详细信息已在配套解读报告中予以说明。用户可通过跨机构洪水风险管理洪水决策支持工具箱网站（https://webapps.usgs.gov/infrm/fdst/）获取本次发布的洪水淹没地图。