Towards a large-scale locally relevant flood inundation modeling framework using SWAT and LISFLOOD-FP

JOURNAL OF HYDROLOGY

卷:581

Article

Rajib, Adnan¹  Liu, Zhu²  Merwade, Venkatesh³  Tavakoly, Ahmad A.^4,5  Follum, Michael L.⁵ 

[1] Texas A&M Univ, Dept Environm Engn, Kingsville, TX USA

[2] Univ Calif Davis, Dept Land Air & Water Resource, Davis, CA 95616 USA

[3] Purdue Univ, Lyles Sch Civil Engn, W Lafayette, IN 47907 USA

[4] Univ Maryland, Earth Syst Sci Interdisciplinary Ctr, College Pk, MD 20742 USA

[5] US Army Engn Res & Dev Ctr, Coastal & Hydraul Lab, Vicksburg, MS USA

关键词: Flood mapping;    Floodplain;    Global flood hazards, hydrologic modeling;    Hydrodynamic modeling;    Ohio River Basin;   

DOI  :  10.1016/j.jhydrol.2019.124406

来源: Elsevier

【 摘 要 】

Lack of geospecificity or local relevance is a major limitation in contemporary large-scale flood modeling frameworks. There is a little practical value for configuring a large-scale model if the model produces streamflow and/or inundation maps only along the large rivers while numerous lower order streams remain overlooked. This study fills the gap through a new flood prediction framework based on the loose coupling of a hydrologic model Soil and Water Assessment Tool (SWAT) and a 1D/2D hydrodynamic model LISFLOOD-FP (hence, SWATLISFP). The prototype SWAT-LISFP framework was configured with similar to 26,000 stream reaches across the similar to 500,000 km(2) Ohio River Basin, United States. After being calibrated against 50 gauge stations across the basin, SWAT simulated streamflow outputs were fed as upstream boundary conditions in LISFLOOD-FP. The resultant flood inundation extents consistently captured 70-80% of the remotely sensed inundation, irrespective of the flood events or locations within the basin. This was also confirmed via cross-validation with an existing flood modeling framework AutoRAPID (Follum et al., 2017). Additional modeling experiments were conducted to facilitate two critical discussions - how simulated inundation extent is affected by the uncertainty in streamflow prediction and the density of streamflow boundary conditions. Taking into account the uncertainties in SWAT streamflow, LISFLOOD-FP showed a remarkable improvement with more than 95% of remotely sensed inundation captured within the simulated extent. While this approach produces a variable-area flood map (i.e., a range of areas likely to be inundated at a particular point of time), inundation in the lower order streams can still remain undetected. A solution to this problem was demonstrated by setting up streamflow boundary conditions across further lower order streams, which subsequently justified the need for high-resolution stream network, and hence, the essence of locally relevant flood inundation modeling. The new contributions of his study, particularly through introducing SWAT as a functional hydrologic alternative to supplement a hydrodynamic model such as LISFLOOD-FP and the series of experiments to draw insights on addressing lack of accuracy and local relevance, will enhance the global flood modeling initiatives.

【 授权许可】

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