The results of the chemical analyses of the river water samples are
summarized in Fig. 1. The highest river water temperatures were
measured during the months of January to March 2010 and October
2010 to January 2011, with a maximum value of 27.2 °C measured in
February 2010. From April to July 2010 the monthly water
temperatures dropped progressively with the lowest value measured
in June 2010 at 11.4 °C. These temperatures correlated with the
changing seasonal temperatures (see Fig. 1). The pH values fluctuated
within a range of 7.05–8.40 over the 13 months with a maximum of
8.40 in January and May 2010. As the pH of raw water is regarded as
suitable for irrigation within a range of 6.50–8.50 (DWAF, 1996b), the
river water samples met this requirement and are therefore not
expected to cause harm to crops or soil. Fluctuations in river water pH
can be caused by nutrient cycling or industrial effluent discharge
(DWAF, 1996a). As the Baynespruit River is passing by a number of
industrial locations along its course, the observed fluctuation in pH
might be due to such discharge. The monthly rainfall was lowest in
July and August 2010 at 0 mm and peaked in January 2010