Association of coal fired power plants with river water quality in South Africa

Abstract

The national power utility owns and operates approximately 95% of the coal-fired power plants (CFPPs) in South Africa. It has been hypothesised that power generation activities lead to the acidification and salination of surface water sources in the vicinity of CFPPs, with upwind sites more polluted than downwind sites. For the purpose of this study, three of power utility's CFPPs were selected, namely Kriel, Komati and Camden Power Plants, which will be reaching the end of their operating lifespan during the mid-to-late 2020 s. The main aim of the study was to analyse the raw water quality data upstream and downstream of these three CFPPs. Raw water supply to the CFPPs for power generation was abstracted from the Rietspruit, Koringspruit and Witpuntspruit streams, respectively. To determine whether the particulate and gaseous emissions affected the water quality from 2012 to 2018, multivariate statistical analyses were applied. The water quality data indicated poor water quality both downwind and upwind of the power plants when thirteen out of 20 (65%) selected water quality variables exceeded the resource quality objectives (RQO) limits, which could be attributed to anthropogenic activities such as agriculture, coal burning and coal mining; causing increased acidity and salinity in the various water sources. In conclusion, the study suggested that there is no direct correlation between the emissions from coal burning and the coal-fired power plants receiving streams; an indication that power generation may not be the only anthropogenic factor influencing the water quality of the streams.