摘要
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.
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.
