How does the water treatment process work?

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1. 1

   Water treatment (Wikipedia)

   WikipediaPublished Oct 10, 2026Checked Oct 11, 2026

   “Water treatment is any process that improves the quality of water to make it appropriate for a specific end-use. The end use may be drinking, industrial water supply, irrigation, river flow maintenance, water recreation or many other uses, including being safely returned to the environment. Water treatment removes contaminants and undesirable components, or reduces their concentration so that the water becomes fit for its desired end-use. This treatment is crucial to human health and allows humans to benefit from both drinking and irrigation use. Advanced water treatment methods have been developed in recent decades due to increased concerns about new pollutants like microplastics, pharmaceuticals, and per- and polyfluoroalkyl substances (PFAS). These include advanced oxidation processes, membrane filtration, and adsorption-based techniques utilizing materials like tailored nanomaterials and activated carbon. Additionally, energy efficiency, resource recovery, and sustainability in water treatment systems are receiving more attention, especially in areas where water is scarce and environmental demands are growing.”

2. 2

   Proliferation of opportunistic premise plumbing pathogens in water treatment plants: Occurrence patterns and influencing factors.

   Water research (Cai et al.)Published Aug 25, 2026Checked Oct 11, 2026

   “Water samples were collected from the intake, coagulation-sedimentation, sand filtration, activated carbon filtration, and finished water stages and analyzed via quantitative PCR (qPCR) with propidium monoazide (PMA) pretreatment to target membrane-intact cells. The results demonstrated that conventional treatment processes inadequately control OPPPs, with the ozone-biological activated carbon (O3-BAC) stage identified as a critical hotspot for pathogen regrowth, which is likely driven by increased microbial activity and organic carbon utilization. Disinfection via chlorination exhibited variable efficacy as measured by PMA-qPCR: while Legionella spp. were relatively susceptible, P. aeruginosa demonstrated higher apparent persistence under chlorination, remaining detectable in finished water. Correlation analyses further linked the occurrence of OPPP to specific water quality parameters and shifts in the microbial community structure. These findings underscore the need for optimized treatment strategies that account for seasonal variations and target OPPP regrowth niches, thereby advancing biosafety control in the drinking water supply.”

3. 3

   [Analysis of Genus-level Algal Breakthrough Patterns and Odor Source Tracking in Drinking Water Treatment Processes Using Machine Learning Approach].

   Huan jing ke xue= Huanjing kexue (Cheng et al.)Published Sep 1, 2026Checked Oct 11, 2026

   “By integrating random forest regression with SHAP interpretable machine learning， we systematically analyzed removal patterns of 32 algal genera across coagulation-sedimentation， filtration， and disinfection processes while achieving biological source tracking of algae-derived odorants. The results showed that coagulation-sedimentation effectively removed Oscillatoria and Synedra， whereas Microcystis， Planktothrix， and Pseudanabaena exhibited high breakthrough potential. Filtration achieved substantial removal for most genera， though flexible filaments of Lyngbya caused filter penetration. Disinfection efficiently inactivated Oscillatoria and Anabaena but proved ineffective against Planktothrix. Source tracking identified Anabaena as the primary producer of 2-MIB， Oscillatoria for geosmin （GSM）， and Microcystis for β-cyclocitral. This study comprehensively characterizes process-specific algal removal susceptibility， providing a data-driven foundation for dynamic process optimization and odor risk control in water treatment plants.”

4. 4

   Impacts of Wastewater Treatment Processes on the Occurrence Characteristics of Microplastics-Taking Four Wastewater Treatment Plants in Northern Henan Province as Examples.

   Toxics (Guo et al.)Published Aug 31, 2026Checked Oct 11, 2026

   “The results revealed that MPs removal efficiencies differed significantly across treatment processes: WWTP4 exhibited the highest comprehensive removal efficiency of 63.89% in the operational situations, followed by WWTP1 of 56.25% and WWTP3 of 51.61%, while WWTP2 exhibited the weakest elimination capacity of 28.12%. It could also be concluded that the differences were primarily governed by biological adsorption and advanced filtration units. Meanwhile, Fragmented and pellet MPs showed higher removal efficiencies than fibrous and film-shaped MPs, while Polymers including PVC, PS, PTFE and PP were more resistant to removal. Longer hydraulic retention time (HRT) and a stable and sufficiently long sludge retention time (SRT) promoted the association of MPs with activated sludge, whereas excessive aeration induced MPs fragmentation and resuspension. Optimizing operational parameters and upgrading advanced filtration facilities could facilitate the regulation and management of MPs. This study provides a theoretical basis for mitigating MPs emissions from municipal WWTPs.”

5. 5

   The hidden hazard in every sip: tackling microplastics in drinking water through detection and mitigation.

   Food chemistry: X (Younis et al.)Published Sep 12, 2026Checked Oct 11, 2026

   “Evidence from worldwide studies demonstrates that MPs are consistently detected in bottled, tap, and groundwater, with substantial variations in abundance, size, morphology, and polymer composition depending on water sources, treatment processes, and distribution systems. Conventional and emerging mitigation approaches, including coagulation-flocculation, membrane filtration, boiling, pulse clarification, and magnetic oxide-based composites, are also critically assessed with respect to their removal efficiencies and practical limitations. Furthermore, the review identifies key research gaps, including the lack of standardized analytical protocols, limited understanding of nanoplastics, and insufficient knowledge regarding long-term human health effects. By integrating current evidence on occurrence, analytical methodologies, health implications, and mitigation strategies, this review provides a comprehensive framework to support standardized monitoring and the development of effective approaches for improving drinking water quality and protecting human health.”

6. 6

   Sewage treatment (Wikipedia)

   WikipediaPublished Oct 10, 2026Checked Oct 11, 2026

   “Sewage treatment is a type of wastewater treatment which aims to remove contaminants from sewage to produce an effluent that is suitable for discharge to the surrounding environment or an intended reuse application, thereby preventing water pollution from raw sewage discharges. Sewage contains wastewater from households and businesses and possibly pre-treated industrial wastewater. There are a large number of sewage treatment processes to choose from. These can range from decentralized systems (including on-site treatment systems) to large centralized systems involving a network of pipes and pump stations (called sewerage) which convey the sewage to a treatment plant. For cities that have a combined sewer, the sewers will also carry urban runoff (stormwater) to the sewage treatment plant. Sewage treatment often involves two main stages, called primary and secondary treatment, while advanced treatment also incorporates a tertiary treatment stage with polishing processes and nutrient removal. Secondary treatment can reduce organic matter (measured as biological oxygen demand) from sewage, using aerobic or anaerobic biological processes.”