Biological Treatment Processes Research Articles

Deciphering the coupling of partial nitrification/anammox and sulfur autotrophic denitrification: Microbial metabolism and antibiotic resistance genes propagation

Partial nitrification/anaerobic ammonium oxidation (anammox) (PN/A) was considered as an economically beneficial and environmentally friendly biological nitrogen removal process. The elimination of nitrate produced by PN/A system was the key to improving the total nitrogen removal efficiency (TNRE) of the system under mainstream conditions. In this study, the feasibility of the coupling S(0)-driven autotrophic denitrification (SAD) with PN/A in a single sequencing moving bed biofilm reactor (SMBBR) at room temperature was explored. Additionally, biological treatment process is ideal environments for the emerge and spread of emerging pollutants antibiotic resistance genes (ARGs), therefore, the shifts of ARGs in the system were investigated. After the coupling of PN/A and SAD, SMBBR was steadily operated with high TNRE. Nitrite-oxidizing bacteria (Nitrospira and Candidatus Nitrotoga) and nitrite oxidoreductase enzyme were inhibited by SAD process. And anammox bacteria were enriched, especially oligotype GAGTTTAAT of Ca. Brocadia. Sulfurimonas became the predominant autotrophic denitrifier. Heterotrophic denitrifiers Thauera and Dechloromonas were elutriated out from the system during the coupling of PN/A and SAD process, and they might be potential hosts for ARGs, leading to the decrease of ARGs. Overall, this study proposed a new strategy that SAD could promote the TNRE of PN/A and cut the risks of ARGs propagation, and PN/A-SAD coupling system was a biological nitrogen removal technology with promising applications under mainstream conditions.

Impacts of dibutyl phthalate on biological municipal wastewater treatment in a pilot-scale A2/O-MBR system

Dibutyl phthalate (DBP) is a typical contaminant in pharmaceutical wastewater with strong bio-depressive properties which potentially affects the operation of municipal wastewater treatment systems. Based on a year-round monitoring of the quality of influent and effluent of a full-scale pharmaceutical wastewater treatment plant in Northeast China, the DBP was found to be the representative pollutant and its concentration in the effluent ranged 4.28 ± 0.93 mg/L. In this study, the negative effects of DBP on a pilot-scale A2/O-MBR system was investigated. When the influent DBP concentration reached 8.0 mg/L, the removals of chemical oxygen demand (COD) and total nitrogen (TN) were significantly inhabited (P < 0.01), with the effluent concentration of 54.7 ± 2.6 mg/L and 22.8 ± 3.7 mg/L, respectively. The analysis of pollutant removal characteristics of each process unit showed that DBP had the most significant effects on the removals of COD and TN in the anoxic tank. The α- and β-diversity in the system decreased significantly when the influent DBP concentration reached 8.0 mg/L. The impacts of DBP on known nitrifying bacteria, such as Nitrospira, and phosphorus accumulating organisms (PAOs), such as Cadidatus Accumulibacter, were not remarkable. Whereas, DBP negatively affected the proliferation of key denitrifying bacteria, represented by Simplicispira, Dechloromonas and Acinetobacter. This study systematically revealed the impacts of DBP on the pollutants removal performance and the bacterial community structure of the biological municipal wastewater treatment process, which would provide insights for understanding the potential impacts of residues in treated pharmaceutical wastewater on biological municipal wastewater treatment.

Recovery Strategies for Heavy Metal-Inhibited Biological Nitrogen Removal from Wastewater Treatment Plants: A Review

Biological nutrient removal is an integral part of a wastewater treatment plant. However, the microorganism responsible for nutrient removal is susceptible to inhibition by external toxicants such as heavy metals which have the potential to completely inhibit biological nutrient removal. The inhibition is a result of the interaction between heavy metals with the cell membrane and the deoxyribonucleic acid (DNA) of the cell. Several attempts, such as the addition of pretreatment steps, have been made to prevent heavy metals from entering the biological wastewater systems. However, the unexpected introduction of heavy metals into wastewater treatment plants result in the inhibition of the biological wastewater treatment systems. This necessitates the recovery of the biological process. The biological processes may be recovered naturally. However, the natural recovery takes time; additionally, the biological process may not be fully recovered under natural conditions. Several methods have been explored to catalyze the recovery process of the biological wastewater treatment process. Four methods have been discussed in this paper. These include the application of physical methods, chelating agents, external field energy, and biological accelerants. These methods are compared for their ability to catalase the process, as well as their environmental friendliness. The application of bio-accelerant was shown to be superior to other recovery strategies that were also reviewed in this paper. Furthermore, the application of external field energy has also been shown to accelerate the recovery process. Although EDTA has been gaining popularity as an alternative recovery strategy, chelating agents have been shown to harm the metal acquisition of bacteria, thereby affecting other metabolic processes that require heavy metals in small amounts. It was then concluded that understanding the mechanism of inhibition by specific heavy metals, and understanding the key microorganism in the inhibited process, is key to developing an effective recovery strategy.

Storage and reactivation of aerobic granular sludge: A review

Aerobic Granular Sludge (AGS) is a biological wastewater treatment process. This technology offers both low land use and cost efficiency. However, the long start-up time is one of the main problems the AGS is facing; to overcome this challenge, several methods have been proposed. Storing and then reactivating AGS is one of the methods proposed. It considerably reduces the start-up time due to skipping most of the granulation procedures. This method collects mature AGS from a running AGS bioreactor, stores it in different forms and environments (depending on the techniques used), and then reactivate the stored AGS when needed. This review summarizes the previously-proposed granules storage techniques such as soaking in different mediums, freezing, and drying. Additionally, the storing techniques are analysed discussing their advantages and disadvantages. The review result indicated that the AGS storage and reactivation method is successful in shortening the lengthy start-up period of the AGS technology. Moreover, storing AGS in dried form using a combination of air drying and dehydration solutions showed a high potential for recovering the removal performance after reactivation. The stored-then-reactivated AGS not only shortens the lengthy start-up period, but it may also lead to an AGS stocking business with further investigation.

Biological Activated Sludge from Wastewater Treatment Plant before and during the COVID-19 Pandemic.

The COVID-19 pandemic and the related measures brought a change in daily life that affected the characteristics of the municipal wastewater and further, of the biological activated sludge. The activated sludge process is the most widely used biological wastewater treatment process in developed areas. In this paper, we aim to show the situation of specific investigations concerning the variation of the physicochemical parameters and biological composition of the activated sludge from one conventional wastewater treatment plant from a metropolitan area. The investigations were carried out for three years: 2019, 2020 and 2021. The results showed the most representative taxa of microorganisms: Microtrix, Aspidisca cicada, Vorticella convallaria, Ciliata free of the unknown and Epistylis and Rotifers. Even if other microorganisms were found in the sludge flocs, their small presence did not influence in any way the quality of the activated sludge and of the wastewater treatment process. That is why we conclude that protozoa (especially Flagellates and Ciliates) and rotifers were the most important. Together with the values and variation of the physicochemical parameters, they indicated a good, healthy, and stable activated sludge, along with an efficient purifying treatment process, no matter the loading conditions.

The effects of light regime on carbon cycling, nutrient removal, biomass yield, and polyhydroxybutyrate (PHB) production by a constructed photosynthetic consortium

Microalgae can add value to biological wastewater treatment processes by capturing carbon and nutrients and producing valuable biomass. Harvesting small cells from liquid media is a challenge easily addressed with biofilm cultivation. Three experimental photobioreactors were constructed from inexpensive materials (e.g. plexiglass, silicone) for hybrid liquid/biofilm cultivation of a microalgal-bacterial consortia in aquaculture effluent. Three light regimes (full-spectrum, blue-white, and red) were implemented to test light spectra as a process control. High-intensity full-spectrum light caused photoinhibition and low biomass yield, but produced the most polyhydroxybutyrate (PHB) (0.14 mg g−1); a renewable bioplastic polymer. Medium-intensity blue-white light was less effective for carbon capture, but removed up to 82 % of phosphorus. Low-intensity red light was the only net carbon-negative regime, but increased phosphorus (+4.98 mg/L) in the culture medium. Light spectra and intensity have potential as easily-implemented process controls for targeted wastewater treatment, biomass production, and PHB synthesis using photosynthetic consortia.

Municipal reclaimed water as makeup water for cooling systems: Water efficiency, biohazards, and reliability

Municipal reclaimed water is increasingly being considered as a sustainable source of makeup water for cooling towers. However, many oil and gas facilities in the water scarce middle eastern regions still depend on non-renewable groundwater for operating cooling towers. Successful application of reclaimed water in a dry desert climate with very high temperature requires a critical understanding of several factors, including water efficiency, biohazards, equipment reliability, and economics. In particular, biohazard assessment, due to bacteria and virus contamination in hot weather, should be assessed to understand the human risks of utilizing reclaimed water. This study investigated the applicability of municipal reclaimed water as an alternative to groundwater for an industrial cooling system at an oil and gas facility in Saudi Arabia. Treated wastewater effluent from an activated sludge biological treatment process was utilized, as make up water for a 4.2 MW cooling tower. The results of this study showed that water efficiency can be increased using municipal reclaimed water instead of groundwater by increasing the cycle of concentration. The bacterial and enteric virus study indicated that the disinfection and biocide treatment was effective in controlling biological growth and minimizing associated risks to human health. The use of reclaimed water was economically viable with 27% reduction in water consumption.

Performance and microbial community of MBBRs under three maintenance strategies for intermittent stormwater treatment

Maintaining microbial activities is a critical problem for biological treatment processes of stormwater runoff because of its intermittent nature. In this study, the suitability of the moving bed biofilm reactor (MBBR) was assessed for stormwater treatment by long-term dry - rainy alternation operation. Three strategies to maintain microbial activities during the dry period, including keeping idle (MBBRI), introducing river water throughout the period (MBBRC), and ahead of a rainy day (MBBRM), were investigated. COD and NH4+-N removal efficiencies declined linearly from 94.2 % and 94.7 % to 51.7 % and 64.6 %, respectively, after the 61-day operation with microbial activity and biomass decreased. Introducing river water adversely affected the process performance as MBBRC presented the highest declining rates of COD and NH4+-N removal efficiencies. Most genera in MBBRs decayed and their microbial communities developed towards individualization, especially in MBBRM because of its highest environmental variability. Keeping idle slightly alleviated the performance decline and formed a more stable microbial community structure. However, significantly deteriorating performance in all MBBRs after the long-term operation indicated that MBBRs were unsuitable for treating stormwater independently of intermittent nature.

B3 공정의 유가공 폐수 처리 특성 평가

As the milk processing wastewater contains large amount of soluble substances and its quality and quantity changes widely, it is not easy to treat efficiently. In this work, we investigated two biological processes for milk processing wastewater treatment, the oxidation ditch process for S Milk Y plant and the B3 process for S Milk G plant. The comparison was made using the one year operation results of these two full-scale plants focusing on the removal of organic matters and nutrients(N, P). Based on the steady state data of the B3 process, hydraulic retention time (HRT) of 3.2 days and sludge retention time (SRT) of 13.8 days were found to be appropriate for milk processing wastewater. Under these conditions the removal efficiencies of organic matters in terms of BOD, CODMn and SS were 99.7%, 98.4% and 99.5%, respectively. In addition, the removal of T-N and T-P amounted to 91.9% and 96.9%, respectively. Therefore, it was confirmed that organic matter and nutrients in milk processing wastewater can be effectively treated with the B3 process if proper operating conditions are maintained. When compared with the oxidation ditch process, the B3 process showed greater removal efficiencies especially for nitrogen and phosphorus.

A review of the biological treatment of leachate: Available technologies and future requirements for the circular economy implementation

Leachate, which refers to dark-colored toxic wastewater generated from landfills, has become an issue of environmental concern, posing a threat to soil, surface water, and groundwater quality, thereby negatively affecting humans’ health. Therefore, it is necessary to select the most appropriate leachate treatment methods considering its complex properties. Among several treatment processes available for this purpose, the biological treatment process is notably effective at removing pollutants and also relatively affordable to operate. Its application to leachate treatment has received much attention in recent years. This study summarizes the leachate characteristics and the methods of leachate treatment with a focus on biological approaches, either aerobic or anaerobic. In addition, this paper concisely discusses the effectiveness and the factors influencing the performance of each treatment technology in case of organics, nutrients, and other pollutants removal. The findings of this paper are expected to provide a deeper insight into the future research and development of leachate treatment, especially the biological treatments concerning the circular economy.

Quantification of greenhouse gas emission from wastewater treatment plants

AbstractIn this study, a new quantitative approach of greenhouse gas (GHG) emissions from wastewater treatment plants (WWTPs) is established. It is developed based on three categories of WWPTs: (1) energy and chemical consumption; (2) final disposal of biosolids; and direct GHG emission from treatment processes, which is helpful to better estimate the GHG emission pathways. The developed approach can provide actual results of GHG emission in terms of carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4) from wastewater treatment process. Then, this method is applied to a municipal WWPT, where the GHG emission from the processes of final treatment, biological treatment, and anaerobic digestion, at the southside of Guelph city in Canada. The results show that there are 6743.8 CO2 eq.kg/day of CO2 and 1924.48 CO2 eq.kg/day of N2O emissions from aeration tank/activated sludge system. The biological treatment and anaerobic digestion release 74177.58 CO 2eq.kg/day of CH4, 7258.5 CO2 eq.kg/day of CO2, and 59022.6 CO2 eq.kg/day of CH4, 3493.24 CO2eq.kg/day of CO2. If the methane, which discharged from biological treatment and anaerobic digestion, is captured and burned for energy regeneration, then it can produce 12937.9 CO2 eq.kg/day of CO2. The total amount of GHG indicates that about 80% GHG is emitted from the final disposal field while 9% and 11% GHG is emitted from biological treatment and anaerobic digestion, respectively. Therefore, based on the calculated results, engineers can put forward suggestions to optimize operation conditions to reduce greenhouse gas emissions. © 2022 Society of Chemical Industry and John Wiley &amp; Sons, Ltd.

A novel Bi2WO6/BiOBr/RGO photocatalyst for enhanced degradation of ciprofloxacin under visible light irradiation: Performance, mechanism and toxicity evaluation

The residual antibiotics in pharmaceutical wastewater have a great impact on the efficiency and stability of wastewater biological treatment process, and prefer to be treated by advanced oxidation process beforehand. In this study, we synthesized a novel Bi2WO6/BiOBr/reduced graphene oxide (RGO) photocatalyst by one-step hydrothermal method and applied it to the photocatalytic oxidation of ciprofloxacin. The characterization results showed that the photocatalyst had a heterojunction structure and a broadening light absorption range. RGO in the composite effectively reduced the band gap of Bi2WO6/BiOBr and promoted the separation of photogenerated charge carriers. Neutral pH condition was favor of the adsorption and degradation of ciprofloxacin by Bi2WO6/BiOBr/RGO, and the ciprofloxacin removal efficiency could be up to 90.7 % with the optimal molar ratio of Bi2WO6 to BiOBr (1:1) and RGO content (5 wt%). In the free radical quenching experiment, superoxide radicals and photogenerated holes were determined to be major contributors for the photocatalytic degradation of ciprofloxacin. Furthermore, 71.3 % of ciprofloxacin could be removed through mineralization during the photocatalysis process, and the residual pollutants did not significantly affect the biological nitrogen removal process.

Treatment of wastewater using black soldier fly larvae, under different degrees of biodegradability and oxidation of organic content

The biological treatment process based on the metabolism of Black Soldier Fly (BSF) larvae proved to be a highly promising technique for the treatment of high organic content (HOC) wastewater, such as sewage from food industries, leachate from municipal solid waste (MSW) landfill, etc. The present study was aimed at achieving a better understanding of how biodegradability and degree of oxidation of organic content might influence treatment performance and biomass quality. Six leachates characterised by similar COD (Chemical Oxygen Demand) but different BOD5/COD (Biochemical Oxygen demand/COD) and TOC/COD (Total Organic Carbon/COD) ratios were tested. By combining these ratios, the BOD5/TOC ratio was introduced to take into account the effect of both leachate properties (biodegradability and oxidation degree). Process treatment performance was significantly influenced by the quality of organic substances. Higher BOD5/TOC values (higher biodegradability and lower oxidation degree) resulted in a greater and faster larvae growth, with final wet weight of between 49.2 and 91.9mg/larva; lower mortality between 5 and 32%; higher prepupation percentages ranging from 4 to 21% and higher specific substrate consumption rate with values varying from 0.051 to 0.063 mgTOC/mg larva/d, up to 3-fold higher than values obtained using conventional activated sludge based on COD consumption. Conversely, no significant differences were detected in larvae protein and lipid contents, including the profiling of fatty acids.

Assessing the effect of SiO2 and TiO2 nanoparticles on granule stability and microbial community shift in aerobic granular sludge process

The widely used SiO2 and TiO2 nanoparticles (NPs) can accumulate in industrial wastewaters, thereby posing challenge to biological wastewater treatment processes. In this work, the performance of aerobic granular sludge (AGS) reactors fed with wastewater containing 50 mg L−1 SiO2 and TiO2 NPs were investigated. The results showed that the granules could resist the NPs in wastewater (no disintegration of granules was observed). SiO2 NPs had a negative effect on the settleability of granules, with the SVI30 increased by 64.5% and protein secretion decreased by 29.9%. To the contrary, the settleability of granules was improved in the presence of TiO2 NPs due to the increase of the protein secretion. Possibly because of the compact and layered structure of granules, in the presence of both types of NPs, no obvious reduction of the overall removal efficiency of organics was found, and nanoparticle-resistant strains were enriched. The overall nitrification and denitrification efficiencies were hardly affected by SiO2 NPs while significantly inhibited by TiO2 NPs. Some functional genera, such as Hyphomicrobium and Acidovorax, showed growth inhibition with TiO2 NPs, which might be responsible for the reduction of nitrification and denitrification efficiencies.

Design of the installation of a small wastewater treatment plant using a Tubular Biological Reactor in the Xochimilco canals

This work proposes the generation of a preliminary project based on the biological treatment process called the Tubular Biological Reactor (RBT), to treat the wastewater discharges that contaminate the Xochimilco canals. The main focus of the work is: through the use of the FEL methodology to generate a design for the installation of a small wastewater treatment plant and thus be able to establish a treatment train based on RBT technology and thus translate it into a diagram of process blocks, subsequently constructing the Process Flow Diagram (DFP) which includes the pre-treatment equipment and main treatments that make up the treatment train, a material balance was prepared that considers urban wastewater as effluent in the tributary of the plant, the systems analyzed in the mass balance are; pretreatment, the sludge produced by the biological reactor as well as its treatment, the aeration systems and the disinfection of the effluent. To comply with NOM- 003- SEMARNAT-1997. With the complete mass balance, the pipeline and instrumentation diagram (DTI) was built and a Layout diagram was made to locate the equipment, this methodology allowed to generate a design that can be applied at various points of the Xochimilco channels, mainly where sewage discharges occur. wastewater treatment; tubular biological reactor.

Heterogeneous photocatalysis and an anaerobic biological process for leachate treatment

The research used a coupling heterogeneous photocatalysis (TiO2-UVsolar) and an anaerobic biological process (Specific Methanogenic Activity Test) to study the treatment of leachate from a landfill in Norte de Santander (Colombia). It developed photocatalysis in a Composite Parabolic Collector (CPC), H2O2 as oxidation assistant, and the combination of different TiO2 levels and pH modeled with a factorial design 32. In the biological test, for a maximum load of 4,500 mg. L-1 of Chemical Oxygen Demand (COD) leachate, 2.0 g. L-1 of Volatile Suspended Solids (VSS) inoculum, and a hydraulic retention time of 23 days, there were no significant COD removal percentages, evidencing the recalcitrant character of these leachates. In the Advanced Oxidation Process (AOP) there was mineralization in terms of DOC of 57%, which evidences the capacity of the process to support the pollutant load of the leachate. The combined process (AOP-Biological) allows additional mineralization in terms of DOC of 21% in the biological process, for a total contribution of the coupling of 78%, which shows the capacity of the AOP to convert toxic wastewater into one with characteristics more suitable for its subsequent degradation in anaerobic biological reactors.

Biological nitrate removal from a drinking water supply with an aerobic granular sludge technology: An environmental and economic assessment

Nitrate pollution of groundwater, mainly from agricultural applications, is a widespread water quality problem in many countries. The aim of this study was to identify and compare the main environmental impacts and costs associated with removing nitrate from groundwater under a conventional treatment technology and a technology based on a biological treatment process (denitrification using aerobic granular sludge). The analysis focused on the first real-world experience of an industrial-scale implementation of said technology, applied to the drinking water supply in a small town in Spain. The methods selected for the environmental and economic evaluations were life cycle assessment and cost-effectiveness analysis, respectively. The drinking water treatment technologies under study were a conventional reverse osmosis plant and a plant using a biological treatment called ecogranularwater. The analysis of these two drinking water production processes was divided into two phases: structure and water treatment. This study demonstrates that the biological technology produces drinking water in a more environmentally-friendly, cost-effective way, and with lower energy costs. The greatest environmental impacts from the reverse osmosis technology occurred in the water treatment phase due to the high levels of energy consumption (up to 1.68 kWh m−3 higher than with the ecogranularwater technology). In the structure phase, the biological technology contributed more than reverse osmosis in all impact categories, with values ranging from 91% in freshwater ecotoxicity to 98% in stratospheric ozone depletion. The cost of producing 1 m3 of water was estimated as 43% lower with the ecogranularwater technology compared to reverse osmosis. In order to further lessen the environmental impact of the biological technology, efforts should be focused on reducing and optimizing energy use and making improvements to the design of the structure. This biological technology proved a good alternative for small and medium-sized municipalities with problems of nitrate-polluted water. The decision to apply technological innovations in drinking water treatments to remove nitrates can be supported by environmental and economic studies.

Treatment of wet electrostatic precipitators wastewater by supercritical water oxidation

ABSTRACT The most commonly used method for treating gas emissions generated during the drying process in chipboard production plants is the Wet Electrostatic Precipitator (WESP). The wastewater generated from the WESP process is considered hazardous due to high pollutants loads and cannot be treated efficiently using conventional treatment methods, such as chemical and biological treatment, sedimentation, and various separation processes. Therefore, there is an urgent need to investigate a novel and efficient treatment method for WESP wastewater. Supercritical water oxidation (SCWO) has recently gained attention as a powerful technique that can remove organic pollutants from wastewater in a short time. In this study, the removal of pollutants from real WESP wastewater was investigated using the SCWO process. The effects of operating conditions; oxidation rate, reaction temperature, and process reaction time, were studied under different experimental conditions. For the SCWO process, optimum conditions 99%, the reaction time of 166 seconds, oxidant ratio of 1.78 and 600°C were determined for 95% yield of total organic carbon (TOC) and total nitrogen (TN). The overall results showed that the TOC and TN removal efficiencies increased with the increase of temperature, oxidant dosage, and reaction time. The result from this study indicated that SCWO is a promising and innovative technique for the treatment of WESP wastewater.

Ammonia oxidation intermediates-induced abiotic transformation of 17α-ethinylestradiol in nitrification process of wastewater biological treatment

17α-Ethinylestradiol (EE2) has aroused growing concern due to its increasing worldwide prevalence and high ecotoxicological risk. It has been reported that the removal of EE2 in the nitrification process of wastewater treatment plants (WWTPs) is attributed to co-metabolism induced by ammonia oxidizers. However, the effect of ammonia oxidation intermediates produced by ammonia oxidizers on the abiotic transformation of EE2 is unclear. In this study, the effect of several ammonia oxidation intermediates, including free nitrous acid (FNA), hydroxylamine (NH2OH), and nitric oxide (NO) on the abiotic transformation of EE2 was evaluated comprehensively. The dynamics of EE2 transformation induced by FNA were affected by the FNA concentration and the initial EE2 concentration. During EE2 nitration induced by FNA, 2,4-nitro-EE2 would be the final nitration product of EE2. FNA-mediated transformation of EE2 was effective for reducing estrogenicity and the transformation was stable under decreased FNA levels or during refrigeration at 4 °C. The key reactive nitrogen species derived from the FNA-induced EE2 nitration reaction have been verified to be nitrogen dioxide (NO2) and/or NO by using a scavenger. Under acidic conditions, NO2 was inferred to be the key reactive nitrogen species inducing the nitration reaction of EE2. As an ammonia oxidation intermediate or FNA-derived species, NO can transform EE2 under alkaline conditions. Unlike FNA and NO, NH2OH could not transform EE2. These findings provide a deeper understanding of the abiotic transformation mechanism of EE2 induced by ammonia oxidation intermediates, exhibiting a significant value in the removal of micropollutants during ammonia oxidation in WWTPs.

Occurrence of coliphage in effluent: A systematic literature review and meta-analysis

Studies have illustrated that wastewater treatment methods targeting bacteria do not remove all types of viruses and available epidemiological studies indicate bacteria concentrations may not always be predictive of viral illnesses associated with recreational water exposure. To address these challenges, coliphages have been proposed as an indicator of fecal contamination in recreational water. When compared to traditional fecal indicator bacteria, coliphages exhibit a longer persistence in the environment. The persistence of coliphages in the environment and through wastewater treatment more closely resembles that of pathogenic viruses. We conducted a systematic literature search of peer-reviewed publications to identify coliphage density data (somatic [SC] and male-specific [MSC]) in wastewater treatment plant (WWTP) effluent categorized as primary, secondary, tertiary treated, or disinfected. Scope, study quality, and data availability were included as literature review inclusion criteria. An analysis was conducted to estimate the coliphage densities for specific treatment types within each respective WWTP effluent category. Densities of MSC and SC in influent were significantly higher when compared to densities of MSC and SC in effluent subjected to secondary treatment using biological treatment processes both with and without nutrient removal, tertiary treatment using either a treatment pond or a phosphate removal process, or disinfection using either chlorine, UV, or a combination of both UV and chlorine. Distributions of coliphage in various wastewater effluents will be useful for evaluating the efficacy of treatment processes and disinfectants in future microbial risk assessments.