1. Ph.D. Candidate, Dept. of Civil and Environmental Engineering, Univ. of Auckland, Auckland 1010, New Zealand (corresponding author). ORCID: .
2. Professor, School of Built Environment, Massey Univ., Private Bag 102904, Albany Campus, Auckland 0745, New Zealand.
3. Professor, Dept. of Environmental Science and Management, Ardhi Univ., P.O. Box 35176, Makongo, Dar es Salaam 14129, Tanzania.
4. Director, Water Resources Division, Ministry of Water, P.O. Box 456, Mtumba, Dodoma 41207, Tanzania.