Funding for this research was provided by:
Water Research Commission of South Africa (2014-2017, [K5/2278/4])
Text and Data Mining valid from 2020-03-05
Received: 24 October 2019
Revised: 22 January 2020
Accepted: 19 February 2020
First Online: 5 March 2020
: There are no potential competing interests in relation to the work presented in this paper.