Physicochemical properties of wastewater effluent from two selected wastewater treatment plants (Cape Town) for water quality improvement

Abstract

Effluent from wastewater treatment plants (WWTPs) is one of the main sources of pollution that seriously affect the physicochemical parameters in water bodies. This occurs particularly when partially treated or untreated effluent is released to various aquatic ecosystems. This constitutes a potential danger to the general environment. To safeguard the lives of human, aquatic and other living organisms, regular monitoring of wastewater effluent to ascertain their compliance with both national and international regulatory limits for water quality improvement is very crucial. This research work was carried out using standard methods to evaluate ten physicochemical parameters from the effluent of two WWTPs in Cape Town, South Africa. Our findings were: temperatures (16.90-25.33 °C), pH (5.85-7.85), EC (923.00-1294.17 µS/cm), TDS (590.72-828.27 mg/L), DO (1.30-5.50 mg/L), SO 4 2− (3.23-163.18 mg/L), COD (23.70-898.58 mg/L), BOD (9.17-252.44 mg/L), Cl − (48.17-378.48 mg/L) and PO 43− (0.10-11.32 mg/L). Temperature, pH and SO 4 2− levels in the two WWTPs were within the recommended limit for wastewater discharge by the Department of Water Affairs and Forestry (DWAF), South Africa and the United State Environmental Protection Agency (USEPA). However, other parameters did not comply fully with both DWAF and USEPA standards. The result showed that effluents from these WWTPs are possible sources of pollution to the receiving water bodies and calls for enhancement of the WWTPs operations to ensure safe effluent discharge.

The use of zebrafish to assess water quality and remediation efforts.

“…Apart from the above-mentioned parameters, pH and total alkalinity indices reported for wastewater SWFE (pH = 9.02 ± 0.16 and 46 0 mg/L total alkalinity) and JB (pH = 5.65 ± 0.02 and 0 mg/L total alkalinity), did not conform to the permissible range. Similar values have been reported for wastewater effluents released into water resources in a number of countries across the world (Santos et al,2008;Singh et al,2012;Ribeiro et al,2020;Butu et al,2022) including developing countries, specifically, SA (Agoro et al,2018;Olabode et al,2020;Phungela et al,2022), suggesting the inefficiency of the treatment works at producing effluents within the water quality guidelines. These observations signalled lack of safety and poor quality of wastewater SWFE and JB for aquatic life.…”

Composites hybridized with Ca(OH)2 and LaMnO3 synergistically improve phosphate adsorption properties

“…When the Ca 0.4 -LMO dosage was 0.05 g L À1 , the phosphate concentration in the pond water decreased to 0.105 mg L À1 , which meets the phosphate discharge standard (0.5 mg L À1 ), 27 and that in the effluent of sanitary wastewater decreased to 0.037 mg L À1 , which meets the U.S. EPA standard (0.05 mg L À1 ). 28 When the Ca 0.4 -LMO dosage was increased to 0.1 g L À1 , the phosphate concentration in the pond water decreased to 0.005 mg L À1 , which meets the U.S. EPA standard (0.05 mg L À1 ). When the Ca 0.4 -LMO dosage reached 0.2 g L À1 , the phosphate concentration in both water bodies was below the detection limit.…”

Nontargeted Screening of Contaminants of Emerging Concern in the Glen Valley Wastewater Treatment Plant, Botswana

“…Antiretrovirals are members of a relatively new class of CECs, which are potentially of key importance in the African continent because more than 19 million people are on treatments for HIV/AIDS (Zitha et al, 2022). Despite this high prevalence, monitoring of ARVs in environmental waters is fairly recent and remains limited to Kenya (K'oreje et al, 2012, 2020; Ngumba et al, 2016), South Africa (Mosekiemang et al, 2019; Olabode, 2021; Wooding et al, 2017), and Zambia (Ngumba et al, 2020). No such study has been conducted in Botswana, despite having an estimated 318 000 people on ARV treatment in 2018 (Adeola & Forbes, 2022).…”