1. Lecturer, School of Civil Engineering Surveying and Construction, Univ. of KwaZulu-Natal, Durban 4041, South Africa (corresponding author).
2. Emeritus Fellow, Dept. of WRD&M, Indian Institute of Technology, Roorkee 247667, India.
3. Scientist F, National Institute of Hydrology, Roorkee 247667, India.
4. Professor, Dept. of WRD&M, Indian Institute of Technology, Roorkee 247667, India.