Assessment of Rainwater Harvesting Reticulation Systems to Reduce High Management Costs in Household Buildings

James Shikuku,Teckla Muhoro,Bernard Mugwima,Victor Nyakundi,Andrew Gremley,Muhammad Ali,Gerryshom Munala

doi:10.4236/nr.2020.114010

Abstract

Rainwater harvesting provides an important alternative source of water in household buildings which increases water security in urban areas. However, high energy cost consumption by the rainwater harvesting systems results in higher management costs which may derail the investment viability of these systems in households. This prompted this study to establish ways through which the management cost of rainwater harvesting systems can be minimized in household buildings. A survey of 200 households from Greenspan, Komarock, Utawala, Kileleshwa and Runda in Nairobi County was undertaken as well as data on the type of rainwater harvesting systems, their operation and maintenance cost collected using observation checklists and questionnaires. The findings indicated that rainwater harvesting typologies 1, 2, 4 and 5 had their water pumped from first-level storage to the second-level storage then supplied to usage points by gravity. Whereas, typologies 3 and 6 had their water moved manually and by gravity respectively. On annual operation cost, 100% of households with typology 3 and 6 spent no money whereas, 100%, 75% and 70.6% with typology 4 and 5, 1 and 2 respectively spent Ksh. 1 - 5000. On annual maintenance cost, 100%, 93.7% and 77.8% of households with typology 5 and 6, 3 and 4 respectively spent Ksh. 1 - 5000 while 25% and 22.2% of households with typology 1 and 2 respectively spent Ksh. 5000 - 10,000. Advanced typology 6 with one-level storage point supplies rainwater to all parts of the household by gravity. This eliminates operation costs spent on energy consumption due to pumping of water, thus minimizing overall management cost spent on rainwater harvesting systems in household buildings.

Highlights

Rainwater harvesting has contributed greatly to increasing water security to governments and individuals living in urban and peri-urban areas [1]
The study’s assessment of RWH reticulation systems in household buildings highlighted that the means through which rainwater is moved in the system determines the level of integration of rainwater into household functions and the management cost spent on these systems
In a bid to optimize the functionality of rainwater, households have resulted in a two-level storage point RWH reticulation typologies 1, 2, 4 and 5

Summary

Introduction

Rainwater harvesting has contributed greatly to increasing water security to governments and individuals living in urban and peri-urban areas [1]. It has been identified as an important alternative source of water in household buildings. Rainwater harvesting is an understood technique that collects clean water for domestic functions in households This technology is done using locally available techniques and material and results in water that is socially acceptable [3]. Rainwater used in buildings and building complexes reduces the demand for water supplied by the municipal It saves energy by reducing the energy consumed for pumping municipal water and mitigate flooding in the impervious urban and peri-urban environment [5]. It helps in reducing social pressure on the urban population when used as an alternative source of water in areas affected by water scarcity challenges

Methods

Results

Conclusion