Potential of rainwater harvesting in urban Zambia

doi:10.1016/j.pce.2003.08.016

Physics and Chemistry of the Earth, Parts A/B/C

Volume 28, Issues 20–27, 2003, Pages 893-896

https://doi.org/10.1016/j.pce.2003.08.016 Get rights and content

Abstract

This paper was associated with a WARFSA funded research project “Potential of rainwater harvesting in urban Zambia”. The general objective of the research was to investigate the applicability of rainwater harvesting in urban Zambia. This paper presents the results obtained at the time of writing the paper. Rainwater harvesting was not new to Zambia and there had been installations which were mainly confined to rural areas. Laboratory analysis of water samples from one such system showed that the water was suitable for drinking purposes. Two peri-urban areas of Lusaka were selected mainly based on the water stress in the areas. The socio-cultural survey conducted in the two areas indicated that water ranked among the top two priorities by the Residential Development Committee. Design of the systems was based on the mass curve analysis for storage and rational formula for the gutters. However, a maximum storage of 10 cubic meters was chosen due to budgetary limitation. Construction of five systems was in progress.

Section snippets

Background

According to the “Social sector rehabilitation and development programme, 1993–1996”, only 43% of the urban population of Zambia had access to safe water and sanitation structures. The situation in Lusaka was similar to most other cities and towns in the whole country and about one-fifth of the country’s population lived in the city. Therefore, Lusaka was used as an example of water and sanitation. Estimates by the JICA study team showed that the safe water coverage in Lusaka was 57% in 1995.

Methodology

Investigating rain collection system technology in existence in Zambia was done by conducting interviews and physical visits. Organisations and institutions which were expected to be involved in rainwater harvesting were contacted. These included Ministry of Agriculture, Livingstone Sustainable Food Programme, Africare, Ministry of Local Government and Housing and Rainwater Harvesting Association of Zambia. A visit was made by the Research team to the Southern Province of Zambia.

Pilot stations

Investigating RWH in Zambia

Rainwater harvesting is a technology which is traditional in some parts of Zambia. It is done on an ad hoc, very low tech basis usually by placing buckets under the eaves to catch rain during storms/storing the water in containers such as old 210 l oil drums. Very few RWH systems had been installed, mainly at schools, but this was not widespread. These were roof harvesting systems consisting of a roof catchment, gutters and tank. The water was drawn through a tap from the tank. The water was

Conclusions

Rainwater harvesting was a technology which existed in some parts of Zambia but it was not widespread. Samples from a roofwater system showed that the water can be used for drinking. Although one can not draw conclusions on the water quality based on one sampling, the indication was that the water which would be harvested from the pilot stations could be used for drinking purposes. Construction of the RWH system chosen was possible using local skills, materials and equipment. Most of the

References (4)

Ettrick, T.M., 1990. An introduction to hydrology. Course Textbook CE 463. University of Zambia, pp....
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