An assessment of the quality of effluent discharged from several wastewater treatment plants into the Crocodile River of Mpumalanga, South Africa

Alber, M., (2002) ‘A conceptual model of estuarine freshwater inflow management’, Estuaries, 25, pp. 1246-1261. doi: https://doi.org/10.1007/BF02692222
Amoah, I.D., Kumari, S., and Bux, F. (2020) ‘Coronaviruses in wastewater processes: source, fate, and potential risks’, Environment International, 143, p.105962. doi: https://doi.org/10.1016/j.envint.2020.105962
Azéma, N., Pouet, M.F., Berho, C. and Thomas, O., (2002) ‘Wastewater suspended solids study by optical methods’, Colloids and Surfaces A: Physicochemical and Engineering Aspects, 204 (1-3), pp.131-140. doi: https://doi.org/10.1016/S0927-7757(02)00006-7
Belabed, B.E. et al. (2017) ‘Modeling seasonal and spatial contamination of surface waters and upper sediments with trace metal elements across industrialized urban areas of the Seybouse watershed in North Africa’, Environmental Monitoring and Assessment, 189, pp.1-19. doi: https://doi.org/10.1007/s10661-017-5968-5
Bertanza, G., Boiocchi, R., and Pedrazzani, R. (2022) ‘Improving the quality of wastewater treatment plant monitoring by adopting proper sampling strategies and data processing criteria’, Science of The Total Environment, 806, p.150724. doi: https://doi.org/10.1016/j.scitotenv.2021.150724
Bilotta, G.S., and Brazier, R.E. (2008) ‘Understanding the influence of suspended solids on water quality and aquatic biota. Water re-search’, 42(12), pp. 2849-2861. doi: https://doi.org/10.1016/j.scitotenv.2021.150724
Bréchet, C. et al. (2014) ‘Wastewater treatment plants release large amounts of extended-spectrum β-lactamase–producing Escherichia coli into the environment’, Clinical Infectious Diseases, 58(12), pp.1658-1665. doi: https://doi.org/10.1093/cid/ciu190
Bunce, J.T., et al. (2018) ‘A review of phosphorus removal technologies and their applicability to small-scale domestic wastewater treatment systems’, Frontiers in Environmental Science, 6, p. 8. doi: https://doi.org/10.3389/fenvs.2018.00008
Chinyama, A., et al. (2016) ‘Occurrence of cyanobacteria genera in the Vaal Dam: implications for potable water production,’ Water SA, 42(3), pp.415-420. doi: https://doi.org/10.4314/wsa.v42i3.06
Chokwe, T.B., et al. (2019) ‘Levels, distributions, and ecological risk assessments of polybrominated diphenyl ethers and alternative flame retardants in river sediments from Vaal River, South Africa’, Environmental Science and Pollution Research, 26, pp.7156-7163. doi: https://doi.org/10.1007/s11356-018-04063-4
Cossío, V., and Wilk, J. (2017) ‘A paradigm confronting reality: The river basin approach and local water management spaces in the Pucara Basin, Bolivia’, Water Alternatives, 10(1), pp.181-194. Available at: https://www.water-alternatives.org/index.php/alldoc/articles/vol10/v10issue1/348-a10-1-10/file?auid=913 (accessed: 17 June 2023 ).
Danladi et al. (2017) ‘Predicting impact of climate change on water temperature and dissolved oxygen in tropical rivers,’ Climate, 5(3), p. 58. doi: https://doi.org/10.3390/cli5030058
De Gisi, S. et al. (2015) ‘An integrated approach for monitoring efficiency and investments of activated sludge-based wastewater treatment plants at large spatial scale’, Science of The Total Environment, 523, pp.201-218. doi: https://doi.org/10.1016/j.scitotenv.2015.03.106
de Klerk, I., van Koppen, K., and van Staveren, M. (2021) ‘Climate stress tests as a climate adaptation information tool in Dutch municipali-ties’, Climate Risk Management, 33, p.100318. doi: https://doi.org/10.1016/j.crm.2021.100318
Dong, G. et al. (2020) ‘Spatio-temporal variation of total nitrogen and ammonia nitrogen in the water source of the middle route of the South-to-North Water Diversion Project,’ Water, 12(9), p. 2615. doi: https://doi.org/10.3390/w12092615
Dong, Y. et al. (2019) ‘Removal of ammonia nitrogen from wastewater: a review,’ Transactions of the ASABE, 62(6), pp.1767-1778. doi: https://doi.org/10.13031/trans.13671
DWA (Department of Water Affairs). 1999. Wastewater limit values applicable to discharge of wastewater into a water resource. Available at: http://hwt.co.za/downloads/NWA%20General%20and%20Special%20Authorisations.pdf (Accessed 17 July 2023).
DWAF (Department of Water Affairs and Forestry). 2004. National Water Resource Strategy. Department of Water Affairs and Forestry, Pretoria. Available at: https://cer.org.za/wp-content/uploads/2017/10/NWRS-2004.pdf. (Accessed 20 June 2023).
Edokpayi, J.N., et al. (2016) ‘Determination and distribution of polycyclic aromatic hydrocarbons in rivers, sediments and wastewater effluents in Vhembe District, South Africa’, International Journal of Environmental Research and Public Health, 13(4), p.387. doi: https://doi.org/10.3390/ijerph13040387
Edokpayi, J.N., Odiyo, J.O. and Durowoju, O.S. (2017) ‘Impact of wastewater on surface water quality in developing countries: a case study of South Africa’, Water Quality, 10 (66561), pp.10-5772. DOI: doi: https://doi.org/10.5772/66561
Evans, P.J., et al. (2019) ‘A comparative pilot-scale evaluation of gas-sparged and granular activated carbon-fluidized anaerobic membrane bioreactors for domestic wastewater treatment’, Bioresource Technology, 288, p.120949. doi: https://doi.org/10.1016/j.biortech.2019.01.072
Greeley, M.S. et al. (2011) ‘Role of a comprehensive toxicity assessment and monitoring program in the management and ecological recovery of a wastewater receiving stream’, Environmental Management, 47, pp.1033-1046. doi: https://doi.org/10.1007/s00267-011-9679-3
Igbinosa, E.O., and Okoh, A.I. (2009) ‘Impact of discharge wastewater effluents on the physico-chemical qualities of a receiving watershed in a typical rural community’, International Journal of Environmental Science & Technology, 6, pp. 175-182. doi: https://doi.org/10.1007/BF03327619
Iloms, E. et al. (2020) ‘Investigating industrial effluent impact on municipal wastewater treatment plant in Vaal, South Africa’, International Journal of Environmental Research and Public Health, 17(3), p.1096. doi: https://doi.org/10.3390/ijerph17031096
Kamika, I., et al. (2021) ‘The occurrence of opioid com-pounds in wastewater treatment plants and their receiving water bodies in Gauteng province, South Africa’, Environmental Pollution, 290, p.118048. doi: https://doi.org/10.1016/j.envpol.2021.118048
Kefford, B.J. (1998) ‘The relationship between electrical conductivity and selected macroinvertebrate communities in four river systems of south-west Victoria, Australia’, International Journal of Salt Lake Research, 7(2), pp.153-170. doi: https://doi.org/10.1007/BF02441884
Kivaisi, A.K., (2001) ‘The potential for constructed wetlands for wastewater treatment and reuse in developing countries: A review,’ Ecological Engineering, 16(4), pp. 545-560. doi: https://doi.org/10.1016/S0925-8574(00)00113-0
Lemessa, F. et al. (2023) ‘Assessment of the Impact of Industrial Wastewater on the Water Quality of Rivers around the Bole Lemi Industrial Park (BLIP), Ethiopia’, Sustainability, 15(5), p. 4290. doi: https://doi.org/10.3390/su15054290
Li, J., and Zuo, Q. (2020) ‘Forms of nitrogen and phosphorus in suspended solids: a case study of lihu Lake, China’, Sustainability, 12(12), p.5026. doi: https://doi.org/10.3390/su12125026
Luo, X. et al. (2015) ‘Treatment of ammonia nitrogen wastewater in low concentration by two-stage ozonization’, International Journal of Environmental Research and Public Health, 12(9), pp.11975-11987. doi: https://doi.org/10.3390/ijerph120911975
Maphanga, T. et al. (2022) ‘The Effect of rainfall on Escherichia coli and chemical oxygen demand in the effluent discharge from the Crocodile river wastewater treatment, South Africa’, Water, 14(18), p.2802. doi: https://doi.org/10.3390/w14182802
Mateo-Sagasta, J. (Ed.) (2017) Reutilizacion de aguas para agricultura en America Latina y el Caribe: estado, principios y necesidades. In Spanish. [Safe and productive use of wastewater in Latin America and the Caribbean: principles, status and needs] Santiago, Chile: FAO.
Mema, V. (2010) ‘Impact of poorly maintained wastewater sewage treatment plants-lessons from South Africa: Wastewater management’, ReSource, 12 (3), pp. 60-65. Available at: https://hdl.handle.net/10520/EJC90239 (Accessed: 15 June 2023).
Mustafa, G. et al. (2024) ‘Effect of nitrite and nitrate-N accumulation and removal on the suspended solids in the aeration tank of Opal’s secondary water treatment plant,’ International Journal of Agriculture & Environmental Science, 11 (1), pp.1-6. doi: https://doi.org/10.14445/23942568/IJAES-V11I1P101
Ngabirano, H., Byamugisha, D., and Ntambi, E. (2016) ‘Effects of seasonal variations in physical parameters on quality of gravity flow water in Kyanamira Sub-County, Kabale District, Uganda’, Journal of Water Resource and Protection, 8(13), pp. 1297-1309. doi: https://doi.org/10.4236/jwarp.2016.813099
Ouali, N., Belabed, B.E., and Chenchouni, H. (2018) ‘Modelling environment contamination with heavy metals in flathead grey mullet Mugil cephalus and upper sediments from north African coasts of the Mediterranean Sea’, Science of the Total Environment, 639, pp. 156-174. doi: https://doi.org/10.1016/j.scitotenv.2018.04.377
Paudel, B., Montagna, P.A., and Adams, L. (2019) ‘The relationship between suspended solids and nutrients with variable hydrologic flow regimes’, Regional Studies in Marine Science, 29, p.100657. doi: https://doi.org/10.1016/j.rsma.2019.100657
Phungela, T. et al. (2021) ‘The impact of wastewater treatment effluent on water resources: A South African perspective’, The Journal of Water Law Available at: https://www.researchgate.net/publication/371370867_Phungela_et_al_2021140-148 (Assessed: 28 July 2023).
Phungela, T.T. et al. (2022) ‘The impact of wastewater treatment effluent on Crocodile River quality in Ehlanzeni District, Mpumalanga Province, South Africa’, South African Journal of Science, 118 (7-8), pp.1-8. doi: https://doi.org/10.17159/sajs.2022/12575
Qadir, M. et al. (2010) ‘The challenges of wastewater irrigation in developing countries’, Agricultural Water Management, 97(4), pp. 561-568. doi: https://doi.org/10.1016/j.agwat.2008.11.004
Romero, E. et al. (2016) ‘Long-term water quality in the lower Seine: Lessons learned over 4 decades of monitoring’, Environmental Science & Policy, 58, pp.141-154. doi: http://dx.doi.org/10.1016/j.envsci.2016.01.016
Sala-Garrido, et al. (2023) ‘Assessing eco-efficiency of wastewater treatment plants: A cross-evaluation strategy.’, Science of The Total Environment, 900, p.165839. doi: http://dx.doi.org/10.1016/j.scitotenv.2023.165839
Sharkawy, M.S. et al. (2021) ‘Integrating near-surface geophysics, remote sensing, and GIS data for assessment of water resources in the northeastern part of the Eastern Desert, Egypt. Ann Geol Surv Egypt, 38, pp.305-316. Available at: https://www.researchgate.net/profile/SultanAraffa/publication/356665680_et_al_201305-316 (Accessed: 05 July 2023).
Teklehaimanot, G.Z., Coetzee, M.A., and Momba, M.N. (2014) ‘Faecal pollution loads in the wastewater effluents and re-ceiving water bodies: a potential threat to the health of Sedibeng and Soshanguve communities, South Africa’, Environmental Science and Pollution Research, 21, pp. 9589-9603. doi: https://doi.org/10.1007/s11356-014-2980-y
Vu, X.S. et al. (2019) ‘Etnlp: A visual-aided systematic approach to select pre-trained embed-dings for a downstream task’, arXiv preprint arXiv:1903.04433. https://doi.org/10.48550/arXiv.1903.04433

Wang, J. et al. (2017) ‘Multivariate statistical evaluation of dissolved trace elements and a water quality assessment in the middle reaches of Huaihe River, Anhui, China’, Science of the Total Environment, 583, pp.421-431. doi: https://doi.org/10.1016/j.scitotenv.2017.01.088
Wu, J. et al. (2017) ‘Spatiotemporal variation of groundwater quality in an arid area experiencing long-term paper wastewater irrigation, northwest China’, Environmental Earth Sciences, 76, pp.1-14. doi: https://doi.org/10.1007/s12665-017-6787-2
Zeng, Z. et al. (2023) ‘Effect of COD/NO3−-N ratio on nitrite accumulation and microbial behavior in glucose-driven partial denitrification system. Heliyon, 9(4). doi: https://doi.org/10.1016/j.heliyon.2023.e1492