Assessing Feasibility of Water Resource Protection Practice at Catchment Level: A Case of the Blesbokspruit River Catchment, South Africa

Abstract

The operationalization of water resource protection initiatives for surface water resource quality and equitable water quality allocation is critical for sustainable socio-economic development. This paper assessed Blesbokspruit River Catchment’s water quality status, using the South African Water Quality standards and Water Quality Index (WQI). Protection levels for quality, and waste discharge for point sources were set and evaluated using the total maximum daily loads (TMDLs) and chemical mass balance (CMB) techniques, respectively. The study found that the water quality results for the analysed physico-chemical parameters (Na+, Ca2+, Mg2+, Cl−, F−, pH, EC, SO42−) of the data collected from 2015 to 2022 were within the limits of the water quality standards, except for NO3− and PO42−. The water quality from the study area was categorized as acceptable for drinking purposes with the WQI of 54.80. The application of the TMDL approach resulted in the 77.96 mS/m for electrical conductivity (EC), 9.92 mg/L for phosphate (PO42−), and 15.16 mg/L for nitrate NO3− being set as the protection levels for the catchment. The CMB was found to be a useful tool for the evaluation of point source discharges into water resources. The study recommends the application of TMDL and CMB techniques in water resource protection practice.

Evaluation of River and Groundwater Quality in the Mzimvubu to Tsitsikamma Water Management Area (WMA7)

“…The mean value of SO 4 was high at the following monitoring stations: N2636 (265.01 mg/L), N3242 (362.53) and ZQMKWD1 (966.90) compared to the target water quality range of 250 mg/L. According to Makanda et al [28], SO 4 is an indicator of general mining impacts. Results for NO 3 + NO 2 value varied from 1.98 mg/L to 2.13 mg/L at the stations N2636 and ZQMADO1, respectively.…”

“…Therefore, the parameter does not pose serious risk but would make the water unsuitable for direct domestic use. EC is an indicator of salinity [28], it fluctuated significantly over the years in the study area. pH values ranged from a minimum of 4.5 to a maximum of 8.2 with a mean value of 7.1.…”

“…pH values ranged from a minimum of 4.5 to a maximum of 8.2 with a mean value of 7.1. According to Makanda et al [28] pH is one of the water quality parameters used to determine the alkalinity (pH > 7), acidity (pH < 7) and neutrality (pH = 7) of water. Therefore, the results of the study showed neutral conditions in the Gamtoos catchment.…”