An investigation of rainwater harvesting in augmenting piped water supply in healthcare facilities within Kampala.
Abstract
Research has shown the need to integrate piped water supply with other water supply types
including rainwater harvesting which has been found to be a promising supplementary source of
water during rainy seasons and periods of intermittency of piped water supply due to increased
water demand following a population increase and other causes. Healthcare Facilities have similar
constraints when it comes to water supply but further challenged by high water bill charges for
piped water supplied the National Water and Sewerage Corporation which is the case for Uganda
and in particular Kampala metropolitan region. The climate of Kampala is well suited for rainwater
harvesting because of the two rainy seasons per year. The quality of rainwater varies from place
to place and depends on environmental conditions, material of the rainwater harvesting system and
management. Since water quality is relative, depending on its usage, there will be variations in
how safety with regards to acquiring water borne and related diseases.
A cross sectional study was conducted in seven healthcare facilities to collect relevant data on the
research with the objective of finding out the types of water supply used, the uses of rainwater for
those carrying out rainwater harvesting and its quality. The methods employed to obtain he
required data and identify possible possibilities of contamination in the collected rainwater
included carrying out site inspections, conducting key informant interviews, questionnaires,
sanitary surveys, physicochemical and bacteriological tests. Rainwater was collected from eight
water tanks and tested for its physical, chemical and bacteriological characteristics in purposively
selected healthcare facilities in both dry and wet seasons for a period of two months.
Findings showed that piped water is the most used type of water supply, followed by rainwater
harvesting which showed the relevance of rainwater; and then water delivered by tanker trucks.
Currently, rainwater was found to be majorly used for non-potable uses however, it was reported
that it can possibly be used for both potable and non-potable uses, taking necessary precautions.
The results from the water quality analysis were compared with the Uganda Standard, US EAS
12: 2014 for natural potable water. Results from the water quality analysis showed that majority
of the physical and chemical parameters were within acceptable drinking water standards.
However, heavy metals like lead and chromium and microbiological parameters exceeded Uganda
standards for natural potable water due to environmental conditions. Therefore, from the results,
the water was not safe for potable uses. This formed a basis for recommending treatment of
rainwater using effective methods which included filtration and disinfection by means of
chlorination. A slow sand filtration system was designed for one of the healthcare guided by the
water design manual from the ministry of Water and Environment.