The contamination of groundwater sources by pathogenic bacteria poses a public health concern to communities who depend totally on this water supply. In the present study, potentially low-cost filter materials coated with silver nanoparticles were developed for the disinfection of groundwater. Silver nanoparticles were deposited on zeolite, sand, fibreglass, anion and cation resin substrates in various concentrations (0.01 mM, 0.03 mM, 0.05 mM and 0.1 mM) of AgNO₃. These substrates were characterised by SEM, EDS, TEM, particle size distribution and XRD analyses. In the first phase, the five substrates coated with various concentrations of AgNO₃ were tested against E. coli spiked in synthetic water to determine the best loading concentration that could remove pathogenic bacteria completely from test water. The results revealed that all filters were able to decrease the concentration of E. coli from synthetic water, with a higher removal efficiency achieved at 0.1 mM (21–100%) and a lower efficiency at 0.01 mM (7–50%) concentrations. The cation resin-silver nanoparticle filter was found to remove this pathogenic bacterium at the highest rate, namely 100%. In the second phase, only the best performing concentration of 0.1 mM was considered and tested against presumptive E. coli, S. typhimurium, S. dysenteriae and V. cholerae from groundwater. The results revealed the highest bacteria removal efficiency by the Ag/cation resin filter with complete (100%) removal of all targeted bacteria and the lowest by the Ag/zeolite filter with an 8% to 67% removal rate. This study therefore suggests that the filter system with Ag/cation resin substrate can be used as a potential alternative cost-effective filter for the disinfection of groundwater and production of safe drinking water.

The main purpose of this study was to implement cost-effective household water treatment systems in every household of Makwane Village for the reduction of diarrhoeal diseases. These household water treatment systems were constructed with locally available materials and consisted of the biosand zeolite-silver impregnated granular clay filters and the silver-impregnated porous pot filters. During the study period (April 2015 to September 2015), the entire village had 88 households with a population size of 480. Prior to the implementation, a survey was conducted and results revealed that 75% (360/480) of the Makwane residents suffered from diarrhoeal disease and the majority of the cases were reported in children that were less than five years of age. Out of the 480 participants, 372 (77.5%) from 70 households accepted the installation of the systems (intervention group) and 108 (25.5%) from 18 households were reluctant to use the systems (the control group). To date, in the intervention group, only 3.8% (14/372) of participants reported cases of diarrhoea. In the control group, 57.4% (62/108) participants reported cases of diarrhoea and most of the episodes of diarrhoea were reported in children of less than five years old (85%), followed by the group aged ≥56 years (75%). The findings of the current study unequivocally demonstrated that the BSZ-SICG and SIPP filters were able to reduce the incidence of diarrhoea by 96.2%. These findings further demonstrate the importance of household water treatment systems (HWTS) interventions in rural areas to bring about meaningful reductions in diarrhoeal diseases by providing safe potable water.

Wastewater treatment and removal of hazardous metals is imperative for the well-being of living things and the environment. Different methods for the removal of hazardous metals have been proposed and practiced with varying success. In this study, dust slag generated by electric arc furnace is utilized for the removal of aluminium, barium and magnesium from industrial effluent. Slag which is a waste generated during the process of steel production is alkaline by nature. It was able to raise the pH of the acidic effluent to 8.7 removing most of the metals and reducing the amount of commercial alkali required to raise the pH to the target pH of 12.5. EAFDS in conjunction with lime removed 98% of Al, 95.8% of Ba and 99.7% of Mg. The method was simple, efficient and cost-effective since it utilizes a material considered hazardous waste for the treatment.

Pollution of water sources is a global issue that primarily affects rural communities that rely on these water sources for domestic purposes on a daily basis. The study’s goal was to determine if the effluent from the Bushbuckridge Municipality’s Waste Water Treatment Works (WWTWs) contributes to the pollution of the Sand River Catchment. The investigation was conducted at two WWTWs, Dwarsloop and Thulamahashe. A questionnaire was used to collect information from participants. Water samples were collected monthly from the treatment plant and Sand River for the determination of physico-chemical parameters and coliform counts. The study found that the WWTWs were the main sources of the pollution of the Sand River Catchment. The WWTWs are confronting unprecedented mechanical and technical challenges. The WWTWs have experienced numerous system failures due to aging systems and pressure on deteriorating facilities, resulting in raw wastewater discharges into catchments. Furthermore, the study revealed that factors such as population growth, poor operation and maintenance of WWTWs, poor budgeting, and a lack of well-trained personnel contributed to WWTW failure. The effluent quality in both WWTWs met the National Water Act of South Africa’s effluent discharge standards for pH (ranged from 6.90 to 9.30), EC (ranged from 20.80 to 87.50 mS/m), ammonia (ranged from 7.22 to 86.80 mg/L as N), nitrate/nitrite (ranged from 0.10 to 0.73 mg/L as N), and ortho-phosphate (ranged from 0.01 to 6.50 mg/L as P). While COD levels in both WWTWs (ranging from 25.00 to 149.00 mg/L) were over the limit during some months of the study period. The study also discovered that E. coli counts were low upstream but high in both the WWTWs point of discharge and downstream for both catchments. The study, therefore, established a connection between wastewater treatment plants and water quality parameters as well as poor water quality linked to the condition of the WWTWs. The study recommends that effective measures be implemented to address the challenges.