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The burgeoning industrialization and urbanization along the Indian coastline have led to an increased prevalence of port infrastructure and effluent discharge, raising concerns about their potential impact on the delicate macrobenthic communities in coastal ecosystems. This comprehensive review aims to evaluate and synthesize existing literature on the ecological repercussions of port activities and effluent discharge on macrobenthic organisms in Indian coastal regions. The study encompasses a thorough analysis of relevant research articles, government reports, and scientific databases, focusing on diverse ecosystems such as estuaries, mangroves, and open coastlines. The review discusses the various stressors associated with port operations, including dredging, habitat alteration, and chemical contamination from effluent discharge. Furthermore, it explores the response mechanisms of macrobenthic communities, encompassing changes in species composition, abundance, and diversity. Special attention is given to the potential long‐term impacts on ecosystem functioning and services. The synthesis of available data enables the identification of knowledge gaps and the formulation of recommendations for future research and management strategies. Understanding the cumulative effects of port activities on macrobenthic communities is crucial for developing sustainable practices and policies to mitigate adverse impacts while fostering the resilience of coastal ecosystems in the face of anthropogenic pressures. This review contributes to the growing body of knowledge on the ecological consequences of human activities in Indian coastal areas, providing valuable insights for researchers, policymakers, and environmental managers alike. [ABSTRACT FROM AUTHOR]

Abstract This study highlights the importance of managing fishpond effluent to minimize its impact on aquatic environments. Fish effluents are a major concern worldwide in aquatic environments. It also provides information on the impacts of effluents on the water quality index of streams when released into aquatic environments. Streams and fishponds were sampled bimonthly for two annual cycles, covering different sampling stations both upstream and downstream of the fishpond effluents at 50-m intervals. Water quality parameters associated with in situ conditions were determined in the field. In the laboratory, other physicochemical parameters were determined via proper standard protocols. The results of the study revealed that water quality parameters such as turbidity, total suspended solids, total solids, conductivity, total dissolved solids, dissolved oxygen, biological oxygen demand and organic matter recorded in water samples collected from 50 m upstream at the point of effluent discharge were significantly (p

This study highlights the importance of managing fishpond effluent to minimize its impact on aquatic environments. Fish effluents are a major concern worldwide in aquatic environments. It also provides information on the impacts of effluents on the water quality index of streams when released into aquatic environments. Streams and fishponds were sampled bimonthly for two annual cycles, covering different sampling stations both upstream and downstream of the fishpond effluents at 50-m intervals. Water quality parameters associated with in situ conditions were determined in the field. In the laboratory, other physicochemical parameters were determined via proper standard protocols. The results of the study revealed that water quality parameters such as turbidity, total suspended solids, total solids, conductivity, total dissolved solids, dissolved oxygen, biological oxygen demand and organic matter recorded in water samples collected from 50 m upstream at the point of effluent discharge were significantly (p < 0.05) different from those recorded at other sampling stations. The WQI value of the discharge point was higher than the WQI recorded in both the upstream and downstream sections of the stream. The findings of this study showed that the point of discharge of fishpond effluents is particularly concerning for the receiving stream compared with other sampling points. This localized area has experienced marked deterioration in water quality, posing significant threats to the health and biodiversity of aquatic ecosystems. The effluent's impact, though slight when dispersed in the receiving waterbody, underscores the necessity for adequate management practices to mitigate its adverse effects. Effective strategies, including regular monitoring, effluent treatment, and sustainable pond management, are imperative to ensure the long-term health and resilience of the aquatic environment. [ABSTRACT FROM AUTHOR]

This study assessed the quality status of the Eruvbi River in Benin City, Nigeria using the National Sanitation Foundation Water Quality Index (NSFWQI). The physicochemical and microbiological parameters analysed were pH, temperature, turbidity, total dissolved solids (TDS), phosphate, nitrate, biochemical oxygen demand (BOD), dissolved oxygen (DO), and total coliforms. All parameters were analysed using standard methods. For each parameter, the temporal and spatial range were pH (5.3 - 6.2), temperature (22.0 - 28.0 oC), turbidity (5.0 - 128.0 NTU), TDS (20.0 - 128.0 mg/L), phosphate (0.1 - 1.0 mg/L), nitrate (0.2 - 0.8 mg/L), BOD (3.4 - 6.2 mg/L), DO (5.0 - 11.2 mg/L), while the mean for total coliform count ranged from (416.9 - 295120.5 CFU/100 mL). The results were compared against national and international standards with the temperature, TDS, and nitrate values within set limits, while the non-conforming parameters were majorly total coliform, phosphate, turbidity, and pH. The overall NSFWQI results indicated moderate water quality, with WQI values ranging from 54.04 to 61.95 at all sampling locations. The middle stream had the lowest NSFWQI value caused by effluent discharge from a carbonated drink industry. The moderate water quality means that additional treatment is required before the water can be considered safe for drinking and domestic purposes. The NSFWQI protocol makes it easier to explain the water quality to the general public and decision-makers, and it can be a valuable tool for water management. [ABSTRACT FROM AUTHOR]

This study assessed the quality status of the Eruvbi River in Benin City, Nigeria using the National Sanitation Foundation Water Quality Index (NSFWQI). The physicochemical and microbiological parameters analysed were pH, temperature, turbidity, total dissolved solids (TDS), phosphate, nitrate, biochemical oxygen demand (BOD), dissolved oxygen (DO), and total coliforms. All parameters were analysed using standard methods. For each parameter, the temporal and spatial range were pH (5.3 - 6.2), temperature (22.0 - 28.0 oC), turbidity (5.0 – 128.0 NTU), TDS (20.0 – 128.0 mg/L), phosphate (0.1 – 1.0 mg/L), nitrate (0.2 - 0.8 mg/L), BOD (3.4 - 6.2 mg/L), DO (5.0 - 11.2 mg/L), while the mean for total coliform count ranged from (416.9 - 295120.5 CFU/100 mL). The results were compared against national and international standards with the temperature, TDS, and nitrate values within set limits, while the non-conforming parameters were majorly total coliform, phosphate, turbidity, and pH. The overall NSFWQI results indicated moderate water quality, with WQI values ranging from 54.04 to 61.95 at all sampling locations. The middle stream had the lowest NSFWQI value caused by effluent discharge from a carbonated drink industry. The moderate water quality means that additional treatment is required before the water can be considered safe for drinking and domestic purposes. The NSFWQI protocol makes it easier to explain the water quality to the general public and decision-makers, and it can be a valuable tool for water management.

Urban wastewater treatment plants (WWTPs) are major contributors of microplastics (MPs) in the environment, despite achieving relatively high removal percentages. This study conducted a comprehensive assessment of the abundance and characteristics of MPs in wastewater and sludge at various treatment stages at Gebze WWTP located in the Marmara Sea, for the first time. The influent exhibited an average MPs concentration of 70.1 ± 28.6 MPs/L. After undergoing the fine screen and grit chamber units, the MPs concentration significantly reduced to 19.7 ± 3.6 MPs/L, indicating an impressive removal rate of 71.8%. Upon completion of the secondary treatment, the effluent contained 7.1 ± 1.7 MPs/L, resulting in an overall MP removal of 89.9–91.0%. The findings indicated that fibers constituted the predominant particle shape, followed by fragments. Fibers were effectively removed through primary treatment (71.8%), while fragments were efficiently removed during secondary treatment (81.1%). The analysis of sludge samples from the aeration basin and sludge thickening tank revealed higher concentrations, with 14.3 and 25 folds increase compared to the influent, respectively indicating the accumulation of MPs in sludge. Despite the treatment process, it is noteworthy that the effluent still exhibited a significant abundance of fibers. Micro-Raman analysis identified polyethylene and polypropylene as the main polymer types present. Although the WWTP demonstrated a high overall removal rate, an estimated 1022.4 × 106 ± 244.8 × 106 MPs/d were still being discharged with the effluent into the Marmara Sea. Recognizing the potential impact of MPs on marine organisms, measures, such as introduction of tertiary treatment processes, were taken to mitigate this issue. [ABSTRACT FROM AUTHOR]

Historically, Southern California's four largest publicly owned treatment works (POTWs) were major sources of contaminants in the Southern California Bight (SCB), home to over 22 million residents and diverse marine life. This study conducted a fifty-year review (1971–2020) to assess these facilities' performance in protecting human and aquatic life. We analyzed effluent discharge flow, total annual mass emissions into SCB, and the rate of change of mass emissions in five ten-year timeframes. Results show a significant decrease in contaminant concentrations (43% to 99%) from 1971 to 2020, with most reaching historically low levels. Despite a growing population, effluent volume decreased by 23%, reflecting successful local water conservation and recycling efforts. Some constituents experienced temporary increases that later decreased. Overall, the decline in mass emissions for all constituents over fifty years highlights the POTWs' efforts to treat effluent and reduce their impact on the SCB's ecosystem. [ABSTRACT FROM AUTHOR]

Kuwait Bay, increasingly susceptible to contamination due to urbanization and effluent discharge, serves as a focal point for environmental research. This study aims to provide a scientifically grounded assessment of sediment contamination within the bay, emphasizing the role of effluents as primary pollutants. Sediments, as repositories for both organic and inorganic pollutants, bear significant implications for marine ecosystems. A systematic sampling approach was employed at forty-six georeferenced sites across the bay, utilizing a grab sampler aboard a research vessel. The sediment samples were rigorously analyzed for inorganic geochemistry, encompassing trace elements, nutrients, and heavy metals. A comparative analysis was conducted between the trace element concentrations obtained in this study and established background levels, as well as the guidelines set forth by the United States Environmental Protection Agency (USEPA). The findings indicate a discernible level of contamination in Kuwait Bay. While the current contamination levels are classified as low, there is a pronounced risk of escalating contamination if the practice of discharging untreated effluents persists. In light of these results, the study underscores the urgent need for effluent decontamination prior to discharge into the bay. This research not only maps the spatial distribution of contaminants in Kuwait Bay but also provides a critical evaluation of potential risks to the marine environment, thereby informing future mitigation strategies. The comprehensive nature of this assessment, integrating geochemical analysis with environmental impact evaluation, marks a significant contribution to the field of marine contamination research. [ABSTRACT FROM AUTHOR]

Due to the difference in density between the discharge effluent and coastal water, partially treated wastewater is often discharged into the marine environment as a buoyant jet via submarine outfalls with multiport diffusers. The dilution characteristics of effluent discharge (dual buoyant jets) in a wavy cross-flow environment were studied in a laboratory. The planar laser-induced fluorescence technique was used to obtain the concentration data of the jets. The effects of different environmental variables on the diffusion and dilution characteristics of the jets were examined through physical experiments, dimensional analysis, and empirical formulations. It was found that the dilution process of the dual jets could be divided into two components: the original jet component and the effluent cloud component. The jet-to-current velocity ratio was the main parameter affecting the concentration levels of the effluent cloud. The merging of the two jets increased the jet concentration in the flow field. When the jets traveled further downstream, the axial dilution increased gradually and then increased significantly along the axis. Under the effects of strong waves, the concentration contours branched into two peaks, and the mean dilution became more significant than under the effects of weak waves. Therefore, the dilution of the effluent discharge was expected to be significant under strong wave effects because the hydrodynamic force increased. A dilution equation was derived to improve our understanding of the dilution process of buoyant jets in a wavy cross-flow environment. This equation was used to determine the influences of the jet-to-current velocity ratio, wave-to-current velocity ratio, and Strouhal number on the minimum jet dilution. It revealed that the wave and buoyancy effects in effluent discharges were significant.

Increasing urbanisation and industrialisation of the Visakhapatnam region have brought domestic sewage and industrial wastewater discharge into the coastal ocean. This study examines the indicator and pathogenic bacteria's quantitative abundance and antibiotic susceptibility. This study collected surface and subsurface water samples from ten different regions (147 stations; 294 samples), including 12 industrial discharge points, surrounding stations and two harbours from the coast of Pydibheemavaram to Tuni. Physicochemical parameters like salinity, temperature, fluorescence, pH, total suspended matter, nutrients, chlorophyll-a and dissolved oxygen showed a difference between regions. We noticed the presence of indicator (Escherichia coli and Enterococcus faecalis) and pathogenic (Aeromonas hydrophila, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella and Shigella, Vibrio cholera and Vibrio parahaemolyticus) bacteria among the samples. Waters from the near harbour and Visakhapatnam steel plant showed lower bacterial load with no direct input from industries to the coastal water. Samples collected during the industrial discharge period had a higher bacterial load, including E. coli. Enteric bacteria were found in higher numbers at most stations. Some isolates were resistant to multiple antibiotics with higher antibiotic resistance and multiple antibiotic resistance indexes compared with the other coastal water habitats in the Bay of Bengal. The occurrence of these bacteria above the standard limits and with multiple antibiotic resistance in the study region may pose a potential threat to the local inhabitants. It can create an alarming situation in the coastal waters in the study region. [ABSTRACT FROM AUTHOR]

Due to climate change, desalination systems have been widely used in recent years as a suitable solution to increase freshwater resources. However, there are some environmental concerns about the disposal of brine water from desalination plants into the sea. In this article, a new probabilistic approach is developed for evaluating the environmental performance of these systems by considering the uncertainties in environmental input data. For this purpose, four levels of desalination plants based on the sizes have been defined. After modeling and performing a deterministic design for each level, the most important variables were identified by employing sensitivity analysis. Afterward, simple formulas for reliability analysis were derived using Bayesian regression to obtain the concentration and dilution of effluents. The sensitivity of these formulas to the input variables was also performed using Sobol analysis. Finally, the Probability of failure (Pf) was calculated for each level using seven reliability methods, including the well-known FORM, SORM, MCS, and four other new methods. Investigations were carried out by considering both the independence and dependence between the variables using the copula function, and the results show the importance of the dependence structure. For example, considering dependence structures based on the Gaussian bivariate copula can decrease the calculated Pf of the four defined levels by nearly 17.5, 21, 27.7, and 39.2%, respectively. The results also show the importance of considering safety factors in actual designs of outfall systems. Implementing safety factors based on an acceptable Pf is a novel approach introduced in this research to control the acceptable hours per year that excess concentration can surpass the environmental criteria. The introduced method can be applied either to design new desalination plants or to evaluate the reliability of existing plants. • A novel approach is developed to evaluate and design water outfalls based on probabilistic environmental criteria. • Variables affecting the performance of desalination outfalls were identified for small to big desalination plants. • Formulas for predicting effluent dilutions were derived using Bayesian regression with a Sobol sensitivity analysis. • Importance of considering variable correlations on the outfall performances is resulted via different reliability methods. • The introduced method is applicable to any new or existing plant and controls the times surpassing environmental criteria. [ABSTRACT FROM AUTHOR]

Assessment of groundwater resource around an abattoir site in Igoba area of Ondo State, southwestern Nigeria has been carried out, within 1.3 km radius from the abattoir site in order to determine the influence of the effluents discharge on quality of groundwater in the area, so as to forestall outbreak of diseases that can endanger human health. Eleven water samples were analyzed for physical, chemical and microbial parameters; and result subjected to spatial and statistical analysis using analysis of variance and Duncan’s multiple range of variance. The obtained parameters mean ± SD are pH (5.5±0.50), turbidity (10±5.9 NTU), temperature (27.75±0.35 °C), conductivity (240±105.99µs/cm), total dissolved solid (158.9±46.8 mg/L), total hardness (92.1±14.2 mg/L), nitrate (7.3±4.3 mg/L), iron (0.24±0.04 mg/L), total alkalinity (14.57±4.87 mg/L), manganese (0.017±0.0079 mg/L), calcium (26.53±8.7 mg/L), magnesium (12.20±8.1 mg/L), chloride (21.86±7.39 mg/L), sodium (14.71±4.85 mg/L), bicarbonate (13.95±4.48 mg/L), nitrite (0.0336±0.0269 mg/L), dissolved oxygen (1.82±0.52 mg/L), chemical oxygen demand (133.1±53.7 mg/L), biological oxygen demand (29.55±10.93 mg/L), total coliform (9.36±6.05 cfu/100ml) and E.coli (0.5090±0.4700 cfu/100ml). The analysis of variance showed that statistically significant difference occurs among the parameters (p

Vertical dense effluent discharges are popular in outfall system designs. Vertical jets provide the opportunity to be efficient for a range of ambient currents, where the jet is pushed away so as not to fall on itself. This study focuses on the worst-case scenario of the dilution and mixing of such jets: vertical dense effluent discharges with no ambient current, in shallow water, where the jet impinges the water surface. This scenario provides conservative design criteria for such outfall systems. The numerical modelling of such jets has not been investigated before and this study provides novel insights into simulations of vertical dense effluent discharges in shallow waters. Turbulent vertical discharges with Froude numbers ranging from 9 to 24 were simulated using OpenFOAM. A Reynolds stress model (RSM) was applied to characterize the geometrical (i.e., maximum discharge rise Zm and lateral spread Rsp) and dilution μmin properties of such jets. Three flow regimes were reproduced numerically, based on the experimental data: deep, intermediate, and impinging flow regimes. [ABSTRACT FROM AUTHOR]

Adulteration is an illegal practice often committed in food and cosmetic industries, yet rarely in environmental regulation compliance. The Chinese Ministry of Ecology and Environment recently issued a law prohibiting any intentional use of 'interfering agents' during wastewater compliance testing. For the first time, such illegal practices are brought to public attention, though they have been barely discussed previously in the scientific literature. The fraudulent method involves the addition into wastewater of a sodium chlorate-based compound, named 'COD remover,' which artificially decreases the chemical oxygen demand (COD) measured during legal testing using the dichromate method. Such practices can decrease COD from 214 mg/L to below 100 mg/L. COD removers are designed to work under testing conditions, and they do not effectively purify wastewater. The use of COD removers has created an underground industry, where users can anonymously purchase those products in 25-kg packages from all major domestic online retailers in China. A notable case was recently publicized after the new legislation, where 131 tons of COD remover had been used in a municipal wastewater treatment plant. Nonetheless, very little is known about other possible cases in China and elsewhere, and whether COD is the sole target of fraudulent practice in wastewater testing. For instance, nitrites could be used as interfering agents in the iodometric method for measuring dissolved oxygen in water and wastewater. There are also reports of chemical adulteration in online monitoring of gas emissions. Since targeted chemical adulteration is based on the knowledge of reactions and mechanisms of testing methods, there is a need to develop more robust and adulteration-proof methods for wastewater testing. [ABSTRACT FROM AUTHOR]

• Effluent discharge amplifies the hyporheic exchange fluxes in the discharge area. • Higher microbiota diversity and complexity was observed in the discharge area. • Lower abundance of keystone taxa led to reduced community stability in EF area. • Keystone taxa largely determine the metabolic functions and community stability. • Controlling efficiency of keystone taxa on metabolic functions reduced in EF area. We lack a clear understanding of how anthropogenic pressures, exemplified by effluent discharge from wastewater treatment plants, destabilize microbial communities in the hyporheic zone (HZ) of receiving rivers. In this study, the spatiotemporal characteristics of hydrological parameters, and the physicochemical properties of surface and subsurface water in a representative effluent-dominated river were monitored. Sequencing of 16S rRNA amplicons and metagenomes revealed the microbial community structure in the HZ of both effluent discharge area and downstream region. The keystone taxa (taxa vital in determining the composition of each microbial cluster) and the keystone functions they controlled were subsequently identified. Effluent discharge amplified the depth of the oxic/suboxic zone and the hyporheic exchange fluxes in the effluent discharge area, which was 50-120% and 40-300% higher than in the downstream region, respectively. Microbial community structure pattern analysis demonstrated an enhancement in the rate of dispersal, an increase in microbial diversity, and an improved community network complexity in the effluent discharge area. By contrast, the number of keystone taxa in the effluent discharge area was 50-70% lower than that of the downstream region, resulting in reduced community network stability and functionality. The keystone taxa controlling metabolic functions in the networks categorized to effluent discharge area were comprised of more genera related to nitrogen and sulfur cycling, e.g., Dechloromonas, Desulfobacter, Flavobacterium, Nitrosomonas , etc., highlighting a research need in monitoring species associated with nutrient element cycling in the HZ of receiving waterbodies. The results showed that the keystone taxa could contribute positively to network stability, which was negatively correlated to hyporheic exchange fluxes and redox gradients. This study provides valuable insights that will improve our understanding of how river ecosystems respond to changes in anthropogenic pressures. [Display omitted] [ABSTRACT FROM AUTHOR]

The temporal variation of the microplastic concentration was studied in the Langueyú stream, which is located in the department of Tandil, in the southeast of the Buenos Aires province in Argentina. This stream receives discharge from the wastewater treatment plants from a medium-sized city. A quantitative analysis of the microplastic concentration was carried out in different samplings, corresponding to different seasons. The study focused on the most contaminated point, located after the discharge of effluents from plants. Higher concentrations of MPs were found in winter (dry season), having approximately 6 times the concentrations found in summer and autumn (wet seasons). However, these differences would not be a direct consequence of the amount precipitation, but rather would be associated with a seasonal variation of human activities, mainly with respect to the type of clothing used in the cold season. The microfibers correspond to around 60–90% of microplastics found. The discharge from the plants causes changes in the parameters of the stream water, such as high electrical conductivity values, and also provide metallic contaminants such as Ca, Zn, and in smaller amounts Pb, Fe, Ni and Cu, which were found adhered to the microplastics and remain in the stream water in high quantities 3 km after the study point. The microplastic concentration presents a linear empirical correlation with the conductivity, and it was found that conductivity measurements would serve as an indicator of the microplastic concentration in the system under study. [Display omitted] • The highest microplastic concentrations were measured in winter (dry season). • There is no direct consequence of precipitation with microplastic concentration. • Discharges from the plants cause changes in the stream water (conductivity and pH). • Conductivity would serve as an indicator of the microplastic concentration. • Metallic contaminants were found adhered to the microplastics. [ABSTRACT FROM AUTHOR]

This study assessed the human health risk of exposure to legacy PAHs in the Nwaenebo River sediments that received effluents for over two decades from the Nigeria National Petroleum Corporation (NNPC) petroleum product Depot in Emene, Enugu, Nigeria. The study went further to estimate economic costs of the sediment PAHs pollution based on the human health risk of exposure. The human health risks were determined by estimating carcinogenic and mutagenic risks via Benzo[a]pyrene total potential equivalent (BaP TPE) and mutagenic equivalent quotient (MEQ). The economic costs of the sediment pollution comprised costs due to mortality and those due to morbidity and were estimated using the value of statistical lives (VSLs) and cost of illness (CoI), respectively. The study, with an appropriate selection of sampling points established that the NNPC petroleum Depot was responsible for the Nwaenebo River sediment PAHs pollution with ƩPAHs concentration 14.3–163 mg/kg. The carcinogenic and mutagenic risks varied from 1.3*10^-5 to 4.7*10^-5 and 1.4*10^-5 to 6.0*10^-5 respectively. Based on risk threshold of 10^-6, these risks were high. The long term economic costs of pollution of the sediments by the PAHs were estimated at 60.5 million USD and 0.46 million USD for mortality and morbidity costs, respectively. [Display omitted] • Nwaenebo river PAHs sediment pollution is due to the Enugu petroleum depot. • The health risk of legacy PAHs due to the petroleum depots is significant. • The 4-and 5-member ring PAHs are predominant in the Nwaenebo River sediment. • The economic cost of legacy PAHs pollution of Nwaenebo River sediment is huge. [ABSTRACT FROM AUTHOR]

Three per cent of Australian agricultural irrigation comes from recycled water. The 1990s establishment of states' Environment Protection Authorities and their regulatory standards and effluent disposal charges led to effluents from Wastewater Treatment Plants (WWTPs) being used for agricultural irrigation. Adelaide and Melbourne, with agricultural land close to plants, expanded intensive vegetable industries. Sydney has limited land available and discharges 90% of its sewage through deep ocean outfalls after primary treatment. Brisbane with more distant farms, found pumping effluent hard to justify economically. Some larger regional cities/towns purchased farms to manage discharges as commercial businesses. Others market recycled water to nearby growers. Uses depend on treatment standards. Water with secondary treatment and pathogen reduction is suitable for processed crops, grazed or cut pastures, sugar cane, cotton and wine grapes, and is widely used for amenity horticulture, but requires careful salinity management. Water with tertiary treatment meeting log reduction pathogen standards may be used on food crops eaten raw (e.g. lettuce). Commonwealth government subsidies during the millennium drought (2001-2009) supported WWTP upgrades and irrigation infrastructure expansion. However, seasonal water demand and unwillingness of growers to pay full cost recovery prices led to some recycled waters still being discharged to water bodies. Some schemes over-estimated likely irrigation demand. Currently, there is scope for further developing recycled water agricultural irrigation by submitting business cases for subsidies from the new National Water Grid Authority. But there is increasing interest in the potential use of recycled water for drinking water augmentation, for which Australia has had guidelines since 2008. Perth has capacity for 28 hm 3 /yr recycled water to replenish its groundwater drinking sources while Brisbane has three plants totalling 84 hm 3 /yr for indirect potable supply, but not yet operating. Recycled water for critical human needs could eventually out-compete agricultural irrigation., Competing Interests: Declaration of competing interest The author declares that he has no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Author. Published by Elsevier B.V. All rights reserved.)