1. Professor Emeritus, Dept. of Hydrology and Hydraulic Engineering, Vrije Universiteit Brussel, Pleinlaan 2, Brussels 1050, Belgium (corresponding author). ORCID: .
2. Visiting Professor, Dept. of Hydrology and Hydraulic Engineering, Vrije Universiteit Brussel, Pleinlaan 2, Brussels 1050, Belgium.
3. Assistant Professor, Dept. of Civil Engineering, Faculty of Engineering, Minia Univ., Minia 61111, Egypt.