Algal removal from cyanobacteria-rich waters by preoxidation-assisted coagulation-flotation: Effect of algogenic organic matter release on algal removal and trihalomethane formation

Impact of harmful algal bloom severity on bacterial communities in a full-scale biological filtration system for drinking water treatment

The occurrence of harmful algal blooms (HABs) in freshwater environments has been expanded worldwide with growing frequency and severity. HABs can pose a threat to public water supplies, raising concerns about safety of treated water. Many studies have provided valuable information about the impacts of HABs and management strategies on the early-stage treatment processes (e.g., pre-oxidation and coagulation/flocculation) in conventional drinking water treatment plants (DWTPs). However, the potential effect of HAB-impacted water in the granular media filtration has not been well studied. Biologically-active filters (BAFs), which are used in drinking water treatment and rely largely on bacterial community interactions, have not been examined during HABs in full-scale DWTPs. In this study, we assessed the bacterial community structure of BAFs, functional profiles, assembly processes, and bio-interactions in the community during both severe and mild HABs. Our findings indicate that bacterial diversity in BAFs significantly decreases during severe HABs due to the predominance of bloom-associated bacteria (e.g., Spingopyxis, Porphyrobacter, and Sphingomonas). The excitation-emission matrix combined with parallel factor analysis (EEM-PARAFAC) confirmed that filter influent affected by the severe HAB contained a higher portion of protein-like substances than filter influent samples during a mild bloom. In addition, BAF community functions showed increases in metabolisms associated with intracellular algal organic matter (AOM), such as lipids and amino acids, during severe HABs. Further ecological process and network analyses revealed that severe HAB, accompanied by the abundance of bloom-associated taxa and increased nutrient availability, led to not only strong stochastic processes in the assembly process, but also a bacterial community with lower complexity in BAFs. Overall, this study provides deeper insights into BAF bacterial community structure, function, and assembly in response to HABs.

Physico-chemical treatments for the removal of cyanotoxins from drinking water: Current challenges and future trends

Cyanobacteria are highly prevalent blue-green algae that grow in stagnant and nutrient-rich water bodies. Environmental conditions, such as eutrophication and human activities, increased the cyanobacterial blooms in freshwater resources worldwide. The excessive bloom formation has also resulted in an alarming surge of cyanobacterial toxins. Prolonged exposure to cyanotoxins is a potential threat to natural ecosystems, animal and human health by the spoilage of the quality of bathing and drinking water. Various molecular and analytical methods have been proposed to monitor their occurrence and understand their global distribution. Moreover, different physical, chemical, and biological approaches have been employed to control cyanobacterial blooms and their toxins to mitigate their occurrence. Numerous strategies have been engaged in drinking water treatment plants (DWTPs). However, the degree of treatment varies greatly and is primarily determined by the source, water properties, and operating parameters such as temperature, pH, and cyanotoxin variants and levels. A comprehensive compilation of methods, from traditional approaches to more advanced oxidation processes (AOPs), are presented for the removal of intracellular and extracellular cyanotoxins. This review discusses the effectiveness of various physicochemical operations and their limitations in a DWTP, for the removal of various cyanotoxins. These operations span from simple to advanced treatment levels with varying degrees of effectiveness and differing costs of implementation. Furthermore, mitigation measures applied in other toxin systems have been considered as alternative strategies.

Application of fluorescence spectra and molecular weight analysis in the identification of algal organic matter-based disinfection by-product precursors

Algal organic matter (AOM) is considered to be threatening for the consumption of disinfectants and the formation of disinfection by-products (DBPs) during the disinfection process. Incompatible parameters in the conventional pretreatment of algal-laden water will lead to counterproductive results, such as AOM release. Therefore, the generation of AOM and its conversion to DBPs during pretreatment should be observed. The characteristics of DBPs from extracellular organic matter (EOM) and intracellular organic matter (IOM) were epitomized and simulation experiments were conducted in deionized (DI) water and source water under pretreatment conditions. Differences in DBP formation between the different backgrounds during chlorination and powdered activated carbon (PAC) treatment were investigated. Instead of monotonous excitation-emission matrix (EEM) spectra, molecular weight (MW) fractionation was simultaneously applied to elucidate the mechanisms of chlorination and PAC adsorption on AOM-based DBPs. The fluorescence regional integration (FRI) EEM results showed a clear correlation between the fluorescent properties and MW distribution of AOM. A decreasing trend was observed after a rapid increase in fluorescence intensity during the chlorination and PAC treatment of water samples in the simulation experiments in deionized (DI) water and source water. The DBP formation potential (FP) in the source water was consistent with the change in AOM during chlorination and PAC adsorption. In addition, EEM showed decent predictability of AOM-based trihalomethanes (THM) FPs (R² = 0.77-0.99) invoking a combination with MW fractionation. Macromolecular protein compounds were highly correlated with the formation of dichloroacetonitrile (DCAN) (R² = 0.89-0.98). These post-mortems results imply that EEM spectra are a useful tool for identifying AOM-based precursors to reveal the accurate environmental fate and risk assessments of AOM.

Transfer organic chloramines to monochloramine using two-step chlorination: A method to inhibit N-DBPs formation in algae-containing water treatment

Organic chloramines formed in chlorination of algae-containing water are typical precursors of nitrogenous disinfection byproducts (N-DPBs). The objective to simultaneously enhance the removal efficiency of organic chloramines and control DBP formation remains a challenge. In this study, we report a two-step chlorination strategy for transferring organic chloramines to monochloramine based on the decomposition mechanisms of mono- and di-organic chloramines, which could limit organic chloramines formation and inhibit N-DBPs formation. We demonstrated that two-step chlorination could decrease the organic chloramines formation by nearly 50% than conventional one-step chlorination. Furthermore, two-step chlorination not only blocked the pathway that organic chloramines decomposed to nitriles, but also led to the conversion of organic chloramines to monochloramine. During two-step chlorination of algal organic matter, the organic chloramine transfer proportion decreased by 6.5% and the monochloramine transfer proportion increased by 17.0%. The N-DBP formation, especially haloacetonitriles (HANs), decreased significantly as organic nitrogen became inorganic nitrogen (monochloramine) in two-step chlorination. This work further clarified the process from algal organic matter to N-DBPs, which could expand our understanding of algae-derived organic chloramines removal and DBPs control.

Molecular transformation of dissolved organic matter and the formation of disinfection byproducts in full-scale surface water treatment processes

Dissolved organic matters (DOM) have important effects on the performance of surface water treatment processes and may convert into disinfection by-products (DBPs) during disinfection. In this work, the transformation of DOM and the chlorinated DBPs (Cl-DBPs) formation in two different full-scale surface water treatment processes (process 1: prechlorination-coagulation-precipitation-filtration; process 2: coagulation-precipitation-post-disinfection-filtration) were comparatively investigated at molecular scale. The results showed that coagulation preferentially removed unsaturated (H/C < 1.0 and DBE > 17) and oxidized (O/C > 0.5) compounds containing more carboxyl groups. Therefore, prechlorination produced more Cl-DBPs with H/C < 1.0 and O/C > 0.5 than post-disinfection. However, the algal in the influent produced many reduced molecules (O/C < 0.5) without prechlorination, and these compounds were more reactive with disinfectants. Sand filtration was ineffective in DOM removal, while microorganisms in the filter produced high molecular weight (MW) substances that were involved in the Cl-DBPs formation, causing the generation of higher MW Cl-DBPs under post-disinfection. Furthermore, the CHO molecules with high O atom number and the CHON molecules containing one N atom were the main Cl-DBPs precursors in both surface water treatment processes. In consideration of the putative Cl-DBPs precursors and their reaction pathways, the precursors with higher unsaturation degree and aromaticity were prone to produce Cl-DBPs through addition reactions, while that with higher saturation degree tended to form Cl-DBPs through substitution reactions. These findings are useful to optimize the treatment processes to ensure the safety of water quality.

Evidence-Based Framework to Manage Cyanobacteria and Cyanotoxins in Water and Sludge from Drinking Water Treatment Plants

Freshwater bodies and, consequently, drinking water treatment plants (DWTPs) sources are increasingly facing toxic cyanobacterial blooms. Even though conventional treatment processes including coagulation, flocculation, sedimentation, and filtration can control cyanobacteria and cell-bound cyanotoxins, these processes may encounter challenges such as inefficient removal of dissolved metabolites and cyanobacterial cell breakthrough. Furthermore, conventional treatment processes may lead to the accumulation of cyanobacteria cells and cyanotoxins in sludge. Pre-oxidation can enhance coagulation efficiency as it provides the first barrier against cyanobacteria and cyanotoxins and it decreases cell accumulation in DWTP sludge. This critical review aims to: (i) evaluate the state of the science of cyanobacteria and cyanotoxin management throughout DWTPs, as well as their associated sludge, and (ii) develop a decision framework to manage cyanobacteria and cyanotoxins in DWTPs and sludge. The review identified that lab-cultured-based pre-oxidation studies may not represent the real bloom pre-oxidation efficacy. Moreover, the application of a common exposure unit CT (residual concentration × contact time) provides a proper understanding of cyanobacteria pre-oxidation efficiency. Recently, reported challenges on cyanobacterial survival and growth in sludge alongside the cell lysis and cyanotoxin release raised health and technical concerns with regards to sludge storage and sludge supernatant recycling to the head of DWTPs. According to the review, oxidation has not been identified as a feasible option to handle cyanobacterial-laden sludge due to low cell and cyanotoxin removal efficacy. Based on the reviewed literature, a decision framework is proposed to manage cyanobacteria and cyanotoxins and their associated sludge in DWTPs.

Effect of Al hydrates on minimization of disinfection-by-products precursors by coagulation with intensified pre-oxidation towards cyanobacteria-laden water

Pre-oxidation is warranted to improve cyanobacteria removal and minimize disinfection by-products (DBPs) precursors for subsequent coagulation with polyaluminum chloride (PACl) in drinking water treatment. However, the reduction in DBP precursors strongly depends on the Al hydrates for PACl coagulation. This study aimed to investigate the effects of intensified NaOCl and ClO₂ pre-oxidation on the removal of Microcystis aeruginosa (MA) and the corresponding halogenated DBP precursors by PACl coagulation with different Al hydrates. Two PACl coagulants, namely PACl-W with 51% monomeric Al and PACl-H with 71% polymeric Al, were used for FlocCAM jar test. The results have shown that the reductions in MA cell and algogenic organic matter (AOM) are more pronounced by sweep flocculation in PACl-W coagulation coupled with NaOCl pre-oxidation. In contrast, ClO₂ pre-oxidation with PACl-H coagulation outperforms the floc formation and the reduction in each fluorescent DOM substance, especially for humic acid-like (HAL) substances reduction in response to charge neutralization. Regardless of pre-oxidation approach, PACl-H coagulation exhibits a superior reduction in carbonaceous DBP formation potential (C-DBPFP) comparative PACl-W coagulation, especially for intensified pre-oxidation (Cl₂:DOC = 3:1). Intensified NaOCl pre-oxidation is effective to enhance DBPFP reduction in a similar way to ClO₂ oxidation by coagulation with both PACl coagulants. In addition, it clearly demonstrates that the halogenated DBP precursors are well-correlated with UV₂₅₄ absorbance on the basis of principal component analysis (PCA) inference. It is concluded that intensified NaOCl pre-oxidation is an alternative approach to ClO₂ pre-oxidation for the minimization of DBP precursors in oxidation-coagulation processes for cyanobacteria-laden water treatment.

Pre-oxidation of Microcystis aeruginosa-laden water by intensified chlorination: Impact of growth phase on cell degradation and in-situ formation of carbonaceous disinfection by-products

Algal growth strongly affects the change in characteristics of algal organic matter (AOM) in algae-laden water. AOM has adverse effects on algal cell removal from natural water by coagulation-sedimentation, frequently results in the significant formation of disinfection by-products (DBPs), such as trihalomethanes (THMs) and haloacetic acids (HAAs). This study aimed to investigate the effects of pre-chlorination on Microcystis aeruginosa (MA)-laden water collected in exponential and decline phases and the corresponding in-situ formed carbonaceous DBPs (C-DBPs) within 10 min exposure time. An automated fluorescent cell counter was used to determine the changes in cell degradation and viability, and fluorescent organic matters were characterized. The results have shown that MA cells suffer a faster and stronger degradation in chlorination at the exponential phase to cause more pronounced viability loss (>70%) than that at the decline phase, resulting in more significant released AOM degradation and C-DBPs formation, especially for THMs formation. In chlorination, a significant degradation in SMP-like and HA-like substances occurs at the exponential phase, while AP-like and SMP-like organics are predominantly degraded at the decline phase. Both THM and HAA precursors play an important role towards in-situ formation of C-DBPs at the exponential phase while THM precursors are dominant at the decline phase. THMs formation decreases with increasing HAAs formation over time during chlorination at the exponential phase, but stagnant THMs and HAAs formation occurs at the decline phase. Intensified pre-chlorination at high dosing ratio (Cl₂:DOC = 1:1) favors to facilitate in-situ formation of THMs. It is concluded that algal growth phase impact on cell removal and C-DBPs formation should be concerned for intensified pre-chlorination towards MA-laden water for drinking water treatment.

The role of hydraulic conditions of coagulation and flocculation on the damage of cyanobacteria

Limited information exists on the damage of harmful cyanobacteria cells, such as Raphidiopsis raciborskii and Dolichospermum circinale, caused by the hydraulic conditions at water treatment plants especially when it comes to the mechanical stresses imposed by coagulation and flocculation. To close this gap, this study evaluated the impacts of rapid and slow-mixing on R. raciborskii and D. circinale cells and trichomes. The hydraulic conditions used during the experiment were selected based on AWWA, which are widely applied in the absence of specific treatability tests. Cellular integrity was evaluated by the Erythrosine B staining method and logistic regression was used to study the association between organism integrity and hydraulic conditions (i.e., velocity gradient and mixing time). Wilcoxon rank-sum test was used to verify if there was a significant reduction of the trichome length and cell integrity. Rapid-mixing (velocity gradient of 750 s^-1 for 60 s) reduced the odds of finding intact D. circinale to <50%, whereas the odds of finding intact R. raciborskii cells did not significantly decrease. The odds of finding intact cells of R. raciborskii were 124 times greater than D. circinale. Rapid-mixing also reduced the length of D. circinale trichomes by approximately 50% but did not significantly decrease R. raciborskii trichomes. Slow-mixing did not significantly affect organisms or trichomes of either species. The results indicate that AWWA recommendations for coagulation may cause damage to D. circinale but not to R. raciborskii, suggesting that the operation of water treatment plants could be adjusted according to the dominant cyanobacterium present in the reservoir to avoid cell rupture and metabolite release.

Disentangling the drivers of Microcystis decomposition: Metabolic profile and co-occurrence of bacterial community

In aquatic ecosystems, water microbial communities can trigger the outbreak or decline of cyanobacterial blooms. However, the microbiological drivers of Microcystis decomposition in reservoirs remain unclear. Here, we explored the bacterial community metabolic profile and co-occurrence dynamics during Microcystis decomposition. The results showed that the decomposition of Microcystis greatly altered the metabolic characteristics and composition of the water bacterial community. Significant variations in bacterial community composition were observed: the bacterial community was mainly dominated by Proteobacteria, Actinobacteria, Planctomycetes, and Bacteroidetes during Microcystis decomposition. Additionally, members of Exiguobacterium, Rhodobacter, and Stenotrophomonas significantly increased during the terminal stages. Dissolved organic matters (DOM) primarily composed of fulvic-like, humic acid-like, and tryptophan-like components, which varied distinctly during Microcystis decomposition. Additionally, the metabolic activity of the bacterial community showed a continuous decrease during Microcystis decomposition. Functional prediction showed a sharp increase in the cell communication and sensory systems of the bacterial communities from day 12 to day 22. Co-occurrence networks showed that bacteria responded significantly to variations in the dynamics of Microcystis decomposition through close interactions between each other. Redundancy analysis (RDA) indicated that Chlorophyll a, nitrate nitrogen (NO₃^--N), dissolved oxygen (DO), and dissolved organic carbon (DOC) were crucial drivers for shaping the bacterial community structure. Taken together, these findings highlight the dynamics of the water bacterial community during Microcystis decomposition from the perspective of metabolism and community composition, however, further studies are needed to understand the algal degradation process associated with bacteria.

Coagulation and disinfection by-products formation potential of extracellular and intracellular matter of algae and cyanobacteria

Coagulation and flocculation can remove particulate algal cells effectively; however, they are not very effective for removing dissolved algal organic matter (AOM) in drinking water plants. In this work, optimum coagulation conditions using alum for both extracellular and intracellular organic matter of six different algal and cyanobacterial species were determined. Different coagulation conditions such as alum dosage, pH, and initial dissolved organic carbon (DOC) were tested. Hydrophobicity, hydrophilicty, and transphilicity of the cellular materials were determined using resin fractionation method. The removal of DOC by coagulation correlated well with the hydrophobicity of the AOM. The disinfection by-product formation potential (DBPFP) of various fractions of AOM was determined after coagulation. Although, higher removal occurred for hydrophobic AOM during coagulation, specific DBPFP, which varied from 10 to 147 μg/mg-C was higher for hydrophobic AOM. Of all the six species, highest DBPFP occurred for Phaeodactylum tricornutum, an abundant marine diatom species, but is increasingly found in surface water.

Minimization of halogenated DBP precursors by enhanced PACl coagulation: The impact of organic molecule fraction changes on DBP precursors destabilization with Al hydrates

The destabilization of halogenated disinfection-by-product (DBP) precursors by coagulation are mostly subjected to Al speciation of polyaluminum chloride (PACl) and the fraction of dissolved organic matter (DOM), which significantly affect the minimization of halogenated DBP precursors, such as trihalomethane (THM) and haloacetic acids (HAA), in post-chlorination. In this study, the destabilization of DOM in the solution of humic acid (HA) with and without algogenic organic matter (AOM) using two PACl coagulants with different Al speciation was investigated, along with the identification of optical properties for DOM fractions. Additionally, total THM and HAA formation potential of the supernatant before and after coagulation-sedimentation were determined. The results showed that high polymeric Al-containing PACl (PACl-H, 66% Al₁₃) outcompetes in destabilizing HA than commercial PACl (PACl-C, 29% Al₁₃, 32% Al(OH)₃). However, the removal of DOM in HA/AOM mixture by both PACl coagulants are significantly suppressed with greater removal of humic-like and fulvic-like substances than aromatic protein-like substances after coagulation-sedimentation, where PACl-C shows superiority in the removal of hydrophobic and hydrophilic substances with MW around 1 kDa than PACl-H. In the absence of AOM, total THM and HAA formation potential were effectively reduced for HA coagulation by both PACl, but vice versa with the presence of AOM, especially for cellular organic matter (COM). Minimization of halogenated DPB precursors by coagulation are predominated by destabilized hydrophilic molecule fractions with Al hydrates. It is concluded that PACl-H favors charge neutralization to destabilize total carbonaceous DBP (C-DBP) precursors in HA or HA/AOM mixture and the corresponding C-DBP formation potential is lower compared to PACl-C that predominates adsorption and co-precipitation in destabilizing C-DBP precursors.

Application progress of enhanced coagulation in water treatment

Water industries worldwide consider coagulation/flocculation to be one of the major treatment methods for improving the overall efficiency and cost effectiveness of water and wastewater treatment. Enhancing the coagulation process is currently a popular research topic. In this review article, the latest developments in enhanced coagulation are summarized. In addition, the mechanisms of enhanced coagulation and the effect of process parameters on processing efficiency are discussed from the perspective of ballast-enhanced coagulation, preoxidation, ultrasound, and composite coagulants. Finally, improvements and new directions for enhanced coagulation are proposed.

This review summarizes the current situation of enhanced coagulation and looks forward to future development.

OH degraded 2-Methylisoborneol during the removal of algae-laden water in a drinking water treatment system: Comparison with ClO2

The growth of algae in water and the taste and odour compounds produced by algal metabolism present a threat to water quality, public health and aquatic ecosystems and cannot be effectively removed by conventional water treatment processes. In this paper, a hydroxyl radical (OH)-based drinking water treatment system (DWTS) with a capacity of 480 m³ per day was built in the Xinglin water plant, Xiamen, China. With pretreatment at 0.88 mg L^-1, sand filtration, and disinfection at 0.31 mg L^-1 during the conveyance of algae-laden water within only 9.8 s, OH removed all five kinds of algae, with a total content of 35,180 cells mL^-1, while ClO₂ treatment left live and dead algae at 7150 cells mL^-1, which would be transported into the pipe networks for the drinking water supply. Meanwhile, OH degraded 2-Methylisoborneol (2-MIB) from 175 to 4.4 ng L^-1, which was below the Chinese standard of 10 ng L^-1, while ClO₂ degraded 2-MIB only to 155 ng L^-1. Based on analyses of the mass spectra database, OH could mineralize 2-MIB by opening the ring structures of 2,2-dimethyl-1,3-cyclopentanedione and 2-methyl-cyclohexenecarboxaldehyde to produce small-molecule compounds. After OH pretreatment and OH disinfection, all water quality and disinfection by-product indexes met the Chinese Sanitary Standards for Drinking Water. Therefore, OH advanced oxidation produced using strong ionization discharge could be practically applied for the degradation of 2-MIB during the treatment of algae-laden water in the OH DWTS.

Physico-chemical processes

The review scans research articles published in 2018 on physico-chemical processes for water and wastewater treatment. The paper includes eight sections, that is, membrane technology, granular filtration, flotation, adsorption, coagulation/flocculation, capacitive deionization, ion exchange, and oxidation. The membrane technology section further divides into six parts, including microfiltration, ultrafiltration, nanofiltration, reverse osmosis/forward osmosis, and membrane distillation. PRACTITIONER POINTS: Totally 266 articles on water and wastewater treatment have been scanned; The review is sectioned into 8 major parts;  Membrane technology has drawn the widest attention from the research community.

Characteristics of growth and microcystin production of Microcystis aeruginosa exposed to low concentrations of naphthalene and phenanthrene under different pH values

Here, Microcystis aeruginosa (M. aeruginosa) was studied to analyze the effects of 0.5 mg L^-1 naphthalene and 0.05 mg L^-1 phenanthrene on profiles of cell growth, chlorophyll-a content and Microcystin-LR (MC-LR) production at different pH values. The results indicated that for both the naphthalene and phenanthrene treatments, the specific growth rates were higher in pH 10.0 than in either pH 7.0 or pH 5.0. In the presence of low concentrations of naphthalene or phenanthrene, chlorophyll-a in medium increased significantly more in pH 10.0 than pH 5.0. chlorophyll-a in cell was significantly lowered when exposed to naphthalene in both pH 10.0 and pH 7.0, and was higher when exposed to phenanthrene in pH 10.0 than pH 5.0. HPLC analysis revealed that the extracellular MC-LR concentrations in M. aeruginosa exposed to either naphthalene or phenanthrene were lower than in control M. aeruginosa at pH 5.0. The intracellular MC-LR levels in toxic M. aeruginosa cells exposed to naphthalene or phenanthrene were higher than in the controls at pH 10.0. Our study suggests that the MC-LR production of M. aeruginosa was affected by the pH value when low concentrations of either naphthalene or phenanthrene were present in the water. These results indicate that the pH value should not be ignored when evaluating the risk of chemicals that promote MC-LR production in eutrophic waters.

Effect of Phenyl-Acyl Compounds on the Growth, Morphology, and Toxin Production of Microcystis aeruginosa Kützing

The proliferation of cyanobacteria and, consequently, the production of cyanotoxins is a serious public health concern; for their control, several alternatives have been proposed, including physical, chemical, and biological methods. In the search for new alternatives and a greater understanding of the biochemical process involved in the blooms’ formation, we report here the effect of eight phenyl-acyl compounds in the growth of Microcystis aeruginosa Kützing (assesed as cell density/count and Chl a fluorescence concentration) morphology, and production of the toxin microcystin-LR (MC-LR). Caffeic acid and eugenol decreased the growth of M. aeruginosa Kützing and the levels of Chl a. However, 3,5-dimethoxybenzoic acid and syringic acid caused the opposite effect in the growth; 2′and 4′only affected the Chl a. A reduction in the concentration of the MC-LR toxin was detected after treatment with syringic acid, caffeic acid, and eugenol. According to HPLC/MS (High Performance Liquid Chromatography coupled to Mass Spectrometry), a redox process possibly occurs between caffeic acid and MC-LR. The optical microscopy and Scanning Electron Microscopy analyses revealed morphological changes that had been exposed to caffeic acid and vanillin, specifically in the cell division and presence of mucilage. Finally, assays in Daphnia pulex De Geer neonates indicated that caffeic acid had a non-toxic effect at concentrations as high as 100 mg/L at 48 h.

Probing algogenic organic matter (AOM) by size-exclusion chromatography to predict AOM-derived disinfection by-product formation

High-performance size exclusion chromatography (HPSEC) coupled with peak-fitting technique was used to probe molecular weight (MW) properties of algogenic organic matter (AOM). The qualitative and quantitative MW information derived was used to predict AOM-derived disinfection by-product (DBP) formation. We resolved overlapping HPSEC chromatograms of all AOM samples into six major peaks with R² > 0.996. This study gave significant insight into the HPSEC profiles of AOM, in which resolved peaks A and B (biopolymers) and peak C (humic substances) showed a strong correlation with the formation of carbonaceous-DBPs (C-DBPs). This likely resulted from the abundance of aromatic structures and conjugated CC double bonds in their chemical nature. Our results also indicated the importance of algal cells, including intra-cellular and cell-bound organic matter, over extra-cellular organic matter as precursors to C-DBP formation. The application of the information extracted from HPSEC profiles associated with the fluorescent components of AOM showed great improvements in the predictability of THMs, HAAs, and C-DBPs with R² > 0.7 and p < 0.05. The outcome of this study will significantly benefit effective control of AOM-derived DBP formation by the chlorination of eutrophic waters.