One Dimensional Shallow Water Equation Streamflow Modeling using WASH123D Model

Abstract

Reservoir inflow forecasting assists dam operator in reservoir operation by providing advance information on lake level. This paper discusses on the application of the physical-based numerical model to simulate one-dimensional channel network using WASH123D Model. The model was developed to simulate streamflow at two locations namely Sg Kejar and Sg Tiang, located in the Temengor catchment. The WASH123D model performed channel routing using shallow water equation. The model input data includes rainfall from 5 rainfall stations, river cross sections and simulated runoff data using SCS Method. Due to unavailable observed data, results comparisons were performed using streamflow results obtained using InfoWorks RS Platform. The peak flow from simulation results at Sg Kejar & Sg Tiang Station is 152.6m3/s and 36.6m3/s. The analysis shows good agreement for both simulations with Nash-Sutcliffe Efficiency of 0.68 for Sg Kejar and 0.99 for Sg Tiang. It is suggested that model recalibration shall be made once there is enough water level data to enable more accurate representation of spatial heterogeneity in the catchment processes.

RETRACTED: Hydrological and climate impacts on river characteristics of Pahang River Basin, Malaysia

“…The Pahang River mainstream at this level has become stable and under control despite an average Sinuosity Index (SI) that is still unstable, but the comparison between the upstream and middle streams gives the impression that the main flow of the river downstream of Pahang is becoming increasingly volatile. However, this area will normally have a problem with high sedimentation, so creating islands of sediment, braided braids, or anastomosed rivers will create a broad flood plain [ [88] , [89] , [90] ]. Based on the analysis of the evolution of the Pahang River main planform, the Sinuosity Index (SI) assessing the evolution of the river was slowly changed through the different aspects of GIS analysis stages, where the error can be reduced because the Sinuosity Index (SI) analysis is carried out based on the river bank as channel length [ 7 , [90] , [91] , [92] ].…”

Predicting River Embankment Failure Caused by Toe Scour Considering 1D and 2D Hydraulic Models: A Case Study of Da-An River, Taiwan

“…The WASH123D model consists of three basic modules: a 1D river routing module, a 2D overland inundation module, and a 3D subsurface computation module. The model has been successfully employed for various applications, including channel flood routing [23,24], river discharge estimations [25,26], and 2D inundation simulations [27,28]. For 1D river routing, the WASH1D model solves the following continuity and momentum equations:…”