Microbial Analysis and Compliance Levels of Wastewater Treatment Using a Nature-Based Solution of Phytoremediation System at National Police College, Rwamagana District, Rwanda

Microbial Analysis and Compliance Levels of Wastewater Treatment Using a Nature-Based Solution of Phytoremediation System at National Police College, Rwamagana District, Rwanda | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Microbial Analysis and Compliance Levels of Wastewater Treatment Using a Nature-Based Solution of Phytoremediation System at National Police College, Rwamagana District, Rwanda Jacques Nsengiyumva, Lillian Adogo, Ihuma Jerome, Temitope Ogunsanya, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9149332/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 17 You are reading this latest preprint version Abstract This research evaluated the microbial status and compliance level of wastewater treated through a nature-based phytoremediation system in Rwanda. Physicochemical parameters such as pH, temperature, total suspended solids (TSSs), total dissolved solids (TDSs), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) were measured and analyzed. The microbial contents, such as total heterotrophic bacteria count, fecal coliform bacteria, total coliform bacteria, E. coli , and helminth eggs, were also investigated. Morphological identification and biochemical tests were conducted via standard techniques. After water treatment in different chambers, the physicochemical parameters were analyzed, and the mean values of the microbial indicators were all within the compliant limits of the Rwanda established water quality standards. The results revealed a decrease in the pH, TSS, BOD₅, COD, TP, HE and microbial counts as the wastewater passed through the initial and middle stages. However, there was a statistically significant decrease in the physicochemical parameters and microbial indicators as the water passed through the final stages of water treatment. These relative and logarithmic decreases indicate polishing and pathogen removal efficiency at the end of the treatment. Therefore, the National Police College phytoremediation system is effective at removing both organic pollutants and pathogenic microorganisms. Compliance Microbial Microorganisms Nature-based Phytoremediation Rwanda Wastewater Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 07 May, 2026 Reviews received at journal 06 May, 2026 Reviews received at journal 03 May, 2026 Reviewers agreed at journal 30 Apr, 2026 Reviewers agreed at journal 29 Apr, 2026 Reviewers agreed at journal 13 Apr, 2026 Reviews received at journal 11 Apr, 2026 Reviewers agreed at journal 30 Mar, 2026 Reviewers agreed at journal 28 Mar, 2026 Reviewers agreed at journal 27 Mar, 2026 Reviews received at journal 27 Mar, 2026 Reviewers agreed at journal 27 Mar, 2026 Reviewers invited by journal 25 Mar, 2026 Editor assigned by journal 24 Mar, 2026 Editor invited by journal 24 Mar, 2026 Submission checks completed at journal 24 Mar, 2026 First submitted to journal 24 Mar, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9149332","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":612886930,"identity":"51364077-6922-430a-a7f7-9234efbd5d4e","order_by":0,"name":"Jacques Nsengiyumva","email":"","orcid":"","institution":"Atlantic International University","correspondingAuthor":false,"prefix":"","firstName":"Jacques","middleName":"","lastName":"Nsengiyumva","suffix":""},{"id":612886931,"identity":"14dc85e9-cc52-4361-af83-c6143724ab87","order_by":1,"name":"Lillian 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