{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,30]],"date-time":"2026-01-30T09:13:21Z","timestamp":1769764401404,"version":"3.49.0"},"reference-count":38,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2023,11,22]],"date-time":"2023-11-22T00:00:00Z","timestamp":1700611200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia (FCT)","doi-asserted-by":"publisher","award":["PD\/BD\/135218\/2017"],"award-info":[{"award-number":["PD\/BD\/135218\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia (FCT)","doi-asserted-by":"publisher","award":["869171"],"award-info":[{"award-number":["869171"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"European Union\u2019s Horizon 2020","award":["PD\/BD\/135218\/2017"],"award-info":[{"award-number":["PD\/BD\/135218\/2017"]}]},{"name":"European Union\u2019s Horizon 2020","award":["869171"],"award-info":[{"award-number":["869171"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sustainability"],"abstract":"<jats:p>Climate change has emerged as a global challenge, with consequences for the environment and societies. To mitigate its impacts, reclaimed water (RW) offers potential by reducing water withdrawal and minimizing pollution discharges in the environment. Safe RW requires disinfection and a sound management of chlorine residuals throughout the RW distribution systems (RWDSs). This study focuses on implementing and calibrating a chlorine decay model using EPANET-MSX in a real RWDS, incorporating both bulk and wall decays. The bulk decay accounts for reactions of monochloramine formation, auto-decomposition, and depletion by a parallel second-order mechanism where monochloramine reacts both with fast and slow organic matter reactive fractions. Two wall decays were considered in the RWDS, one in the tank, modeled through an overall wall decay constant, and one in the pipes, modeled through a wall decay constant. Field experiments were conducted to calibrate the complete model. This model was used as a support tool to diagnose the RWDS status condition and cleaning needs, and to manage its operation. Through simulated scenarios considering monochloramine wall decays similar to those observed in drinking water distribution systems, the model allowed predicting adequate chlorine dosing in summer and winter scenarios, so as to guarantee monochloramine concentrations between 1 mg\/L and 5 mg\/L through the network. These results point to the potential use of much lower doses than the ones currently applied.<\/jats:p>","DOI":"10.3390\/su152316211","type":"journal-article","created":{"date-parts":[[2023,11,22]],"date-time":"2023-11-22T10:41:51Z","timestamp":1700649711000},"page":"16211","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Modeling Chlorine Decay in Reclaimed Water Distribution Systems\u2014A Lisbon Area Case Study"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3302-897X","authenticated-orcid":false,"given":"Joana","family":"Costa","sequence":"first","affiliation":[{"name":"Urban Water Unit, Hydraulics and Environment Department, LNEC\u2014National Laboratory for Civil Engineering, Av. Brasil 101, 1700-066 Lisbon, Portugal"},{"name":"CERIS, Instituto Superior T\u00e9cnico, University of Lisbon, Av. Rovisco Pais 1, 1049-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3976-4123","authenticated-orcid":false,"given":"Elsa","family":"Mesquita","sequence":"additional","affiliation":[{"name":"Urban Water Unit, Hydraulics and Environment Department, LNEC\u2014National Laboratory for Civil Engineering, Av. Brasil 101, 1700-066 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9616-295X","authenticated-orcid":false,"given":"Filipa","family":"Ferreira","sequence":"additional","affiliation":[{"name":"CERIS, Instituto Superior T\u00e9cnico, University of Lisbon, Av. Rovisco Pais 1, 1049-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4334-8213","authenticated-orcid":false,"given":"David","family":"Figueiredo","sequence":"additional","affiliation":[{"name":"\u00c1guas do Tejo Atl\u00e2ntico, S.A., F\u00e1brica de \u00c1gua de Alc\u00e2ntara, Avenida de Ceuta, 1300-254 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5705-366X","authenticated-orcid":false,"given":"Maria Jo\u00e3o","family":"Rosa","sequence":"additional","affiliation":[{"name":"Urban Water Unit, Hydraulics and Environment Department, LNEC\u2014National Laboratory for Civil Engineering, Av. Brasil 101, 1700-066 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2034-9838","authenticated-orcid":false,"given":"Rui M. C.","family":"Viegas","sequence":"additional","affiliation":[{"name":"Urban Water Unit, Hydraulics and Environment Department, LNEC\u2014National Laboratory for Civil Engineering, Av. Brasil 101, 1700-066 Lisbon, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,22]]},"reference":[{"key":"ref_1","unstructured":"Economic European Communities (1991). Council Directive 91\/271\/EEC of 21 May 1991 Concerning Urban Waste Water Treatment. Off. J. Eur. Communities, L135, 40\u201352."},{"key":"ref_2","unstructured":"European Commission (2022). Proposal for a Directive of the European Parliament and of the Council Concerning Urban Wastewater Treatment, European Commission."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2739","DOI":"10.2166\/wst.2013.180","article-title":"Constructed wetlands for combined sewer overflow treatment in a Mediterranean country, Portugal","volume":"67","author":"Amaral","year":"2013","journal-title":"Water Sci. Technol."},{"key":"#cr-split#-ref_4.1","unstructured":"European Commission (2020). 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Water Treat."}],"container-title":["Sustainability"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2071-1050\/15\/23\/16211\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T21:27:36Z","timestamp":1760131656000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2071-1050\/15\/23\/16211"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,11,22]]},"references-count":38,"journal-issue":{"issue":"23","published-online":{"date-parts":[[2023,12]]}},"alternative-id":["su152316211"],"URL":"https:\/\/doi.org\/10.3390\/su152316211","relation":{},"ISSN":["2071-1050"],"issn-type":[{"value":"2071-1050","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,11,22]]}}}