Evaluation of the risks associated with the use of Rooftop Rainwater Harvesting and Groundwater for Domestic use and Livestock Watering (Volume 2) Chemical Quality of Groundwater for Potable Use and Livestock Watering.

Background Water quality constituents (WQC) may be inorganic and organic chemicals, which occur either as natural features of all water sources, or as a result of non-natural features related to anthropogenic activities. This report deals with the potential risk to consumers associated with the ingestion of inorganic WQC that may either be of natural or non-natural origins. In the event of naturally occurring inorganic chemicals, the ranges and concentrations vary according to the nature of the geological and rainfall circumstances. The sources of non-natural WQC are associated with anthropogenic activities including agriculture and mining, manufacturing industries and the settling of people in towns and cities. The potential health risk to domestic consumers and livestock is determined by a complex interaction of parameters that include the concentrations of WQC, the ingestion rates via the water intake (WI) rates and the biological susceptibility of domestic consumers and livestock to a particular inorganic chemical WQC. Risks increase by increasing concentrations and/or WI rates, according to the fate of ingested WQC in the body and consumers’ biological characteristics. This research assesses the quality of water as a potential health risk in terms of inorganic WQC in rooftop harvested rainwater (RRWH), groundwater (GW), river water (RW) and municipal water (MW) sources to people and livestock due to an intake of WQC exceeding water quality guideline (WQG) values. The research is intended to propose changes to the WQG values on GW for domestic use and livestock watering. It is anticipated that the proposed study will generate new knowledge that will inform society of the potential risks associated with the use of these waters resources. In addition, the outcomes of such a study will promote the safe use and appropriate applications of these water resources. The knowledge will enable the relevant national, provincial and local government departments to develop effective intervention strategies and establish appropriate guidelines and regulations. Aims and objectives The overall aim of the project was to evaluate potential health risks associated with the use of rooftop harvested rainwater for domestic use and groundwater for domestic use and livestock watering.