Abstract
M.Sc. (Environmental Science)
The natural condition of the Orange River should be evaluated in order to develop baseline
information so that it can be used for comparison, monitoring and informed decision-making. This
will also allow for further research to take place. Although there is a lot of data available on
the Orange River, little work has been done on the evaluation of the natural conditions that
influence the inorganic water chemistry
Inorganic data, from 1986 to 2006, obtained from the Department of Water Affairs and
Forestry (DWAF) was evaluated for six sample stations along the Orange River
(D1H009Q01, D3H008Q01, D3H012Q01, D3H013Q01, D7H008Q01 and D7H005Q01).
Climate data (1986-2006) was obtained from the South African Weather Service.
The following water quality data was used in the evaluation: pH and the concentrations
of major elements (all in mg/L). The major elements include sodium (Na + ), potassium
(K + ), calcium (Ca ²+ ), magnesium (Mg ²+ ), silica (Si ⁴+ ), fluoride (F - ),
orthophosphate (PO ³- ), chloride (Cl - ), total alkalinity (TAL) assumed to be bicarbonate (HCO -
), sulphate (SO ²- ),
3 4
nitrate (NO - ) (assuming that NO - >>> NO - ) and the total dissolved solids (TDS). Various
3 3
2
geochemical techniques were used to analyse the data...