Journal of Water Resource and Protection, 2019, 11, 896-935 http://www.scirp.org/journal/jwarp ISSN Online: 1945-3108 ISSN Print: 1945-3094 DOI: 10.4236/jwarp.2019.117055 Jul. 31, 2019 896 Journal of Water Resource and Protection The Implication of Unreliable Urban Water Supply Service: The Case of Vendor Water Cost in Langata Sub County, Nairobi City, Kenya E. A. Ochungo 1* , G. O. Ouma 2 , J. P. O. Obiero 3 , N. A. Odero 4 1 Institute for Climate Change and Adaptation (ICCA), University of Nairobi, Nairobi, Kenya 2 Department of Meteorology, University of Nairobi, Nairobi, Kenya 3 Environmental and Biosystems Engineering, School of Engineering, University of Nairobi, Nairobi, Kenya 4 Department of Electrical and Electronics Engineering, Machakos University, Machakos, Kenya Abstract Studies on urban water supply service improvements continue to draw inter- est across the world. The pressure on freshwater resources is increasing in every region in the face of an increasing demand and climate change dynam- ics. Langata sub County in Nairobi city, Kenya faces drought induced water shortage and households rely on water vending and bottled water purchases to augment the inadequate municipal water supplies. Little to our knowledge has been done to assess the cost implication of such a practice here. So the study used household survey method to collect monthly households’ water bills comprising; utility company, water tanker delivery and bottled water purchase from a randomly sampled 382 households spread within the five wards; Karen, South C, Mugumoini, Nairobi West and Nyayo Highrise. The gated communities identified are 57. Simple stochastic analysis of the data was done after data cleaning using MS Excel. It was found that the municipal water serves up to 91.15% of the total average household monthly water de- mand with a cost share of 27.91%. Water tanker delivery meets 8.61% of the household water demand with a cost share of 50.74%. The bottled water pur- chases serve 0.24% of a typical household water demand with a total cost share of 21.35%. The water supply deficit which is a mere 8.85% met by tank- er deliveries and bottled water purchases has a total average cost share of 72.09%. The computed cost burden is 258%. This means that the households pay more than two and a half times extra above the utility bill per month. The study recommends a new water policy that will incorporate the role of water vendors operated on a cooperative model by the gated communities using standard guidelines. How to cite this paper: Ochungo, E.A., Ouma, G.O., Obiero, J.P.O. and Odero, N.A. (2019) The Implication of Unreliable Urban Water Supply Service: The Case of Vendor Water Cost in Langata Sub County, Nairobi City, Kenya. Journal of Water Resource and Protection, 11, 896-935. https://doi.org/10.4236/jwarp.2019.117055 Received: June 13, 2019 Accepted: July 28, 2019 Published: July 31, 2019 Copyright © 2019 by author(s) and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access