Flood modelling improvement using automatic calibration of two dimensional river software SRH-2D

摘要

River model calibration is essential for reliable model prediction. The manual calibration method is laborious and time-consuming and requires expert knowledge. River engineering software is now equipped with more complex tools that require a high number of parameters as input, rendering the task of model calibration even more difficult. This paper presents the calibration tool O.P.P.S. (Optimisation Program for PEST and SRH-2D) and then uses it in multiple calibration scenarios. O.P.P.S. combines PEST, a calibration software and SRH-2D, a bi-dimensional hydraulic and sediment model for river systems, into an easy-to-use set of forms. O.P.P.S is designed to minimise the user's interaction with the involved program to carry out rapid and functional calibration processes. PEST uses the Gauss-Marquardt-Levenberg algorithm to adjust the model's parameters by minimising an objective function containing the differences between field observation and model-generated values. The tool is used to conduct multiple calibration series of the modelled Ha! Ha! river in Qu,bec, with varying information content in the observation fields. A sensitivity study is also conducted to assess the behaviour of the calibration process in the presence of erroneous or imprecise measurements.