Global assessment of how reservoirs and desalination plants enhance human water security

Global assessment of how reservoirs and desalination plants enhance human water security | 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 Article Global assessment of how reservoirs and desalination plants enhance human water security Akiko Matsumura, Noata Hanasaki, Takahiro Oda, Daikichi Ogawada, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8116124/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Water scarcity arises not only from chronic water shortage but also from seasonal and interannual variability. Water infrastructure fills the gaps in water requirements and sustainably available water. However, its role in mitigating water deficits and the differences across regions have been insufficiently explored. Here, we quantify the contribution of reservoirs and desalination plants (RDs) in reducing water deficits using a global hydrological model and indicators that capture spatiotemporal dynamics. We find that RDs substantially reduce global water deficits and that their functions vary regionally: seasonal reallocation dominates in Asian monsoon regions, whereas interannual buffering is more prominent in regions of the Southern Hemisphere. Globally, RDs alleviate water deficits equivalent to more than 5% of the global human water requirements on average and over 13% during drought periods. These findings provide a quantitative assessment of how water infrastructure contributes to water security across regions with differing hydroclimatic and socioeconomic conditions. Earth and environmental sciences/Hydrology Earth and environmental sciences/Environmental social sciences/Sustainability Full Text Additional Declarations Yes there is potential Competing Interest. A.M., T. Oda, and D.O. were employed by Nippon Koei Co., Ltd. during the course of this work. Supplementary Files 02.ManuscriptSupplementary.pdf Supplementary information for “Global assessment of how reservoirs and desalination plants enhance human water security Cite Share Download PDF Status: Posted Version 1 posted 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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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-8116124","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":546450990,"identity":"03525835-ee00-4271-8e11-a2ff4bc8c78a","order_by":0,"name":"Akiko Matsumura","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA7UlEQVRIiWNgGAWjYJADZoYPDAwGDAyMDQwSBBTCWYwzSNbCzAPWQgDotp8//Jk353A+fwPzY2PbHQzG/OzNDQyWO3BrMTuTzCbNu+2w5YwDbMbJuWcYzCR7DjYwSJ7Bo+VAMhszUIsBw/0Hxodz2/7bGNxIBGppw6Pl/GPmzyAt8gfYPx+2bGOwMbj/kICWG8kMIIcZGBzgMU5mbGMwM7jBSEjLYzPJudvSDQwP8BQb9rYxGEv2JDYcwOuX84mPP7zdZm0gd4B9s8TPNgbDfvbjDx9L4gkx7OCwZAOpWhg/kqxlFIyCUTAKhjEAAGV1TbSRc+1UAAAAAElFTkSuQmCC","orcid":"https://orcid.org/0000-0003-4933-1161","institution":"Nippon Koei Co., Ltd.","correspondingAuthor":true,"prefix":"","firstName":"Akiko","middleName":"","lastName":"Matsumura","suffix":""},{"id":546450991,"identity":"9568a862-deb6-48d3-8ef2-64f85bc64a2c","order_by":1,"name":"Noata Hanasaki","email":"","orcid":"https://orcid.org/0000-0002-5092-7563","institution":"National Institute for Environmental Studies","correspondingAuthor":false,"prefix":"","firstName":"Noata","middleName":"","lastName":"Hanasaki","suffix":""},{"id":546450992,"identity":"2fe50e09-3237-420f-9733-ab722b1b693a","order_by":2,"name":"Takahiro Oda","email":"","orcid":"","institution":"aiESG, Inc.","correspondingAuthor":false,"prefix":"","firstName":"Takahiro","middleName":"","lastName":"Oda","suffix":""},{"id":546450993,"identity":"5cb31ccb-ad30-4c44-8178-3f124e911a47","order_by":3,"name":"Daikichi Ogawada","email":"","orcid":"","institution":"Nippon Koei Co., Ltd.","correspondingAuthor":false,"prefix":"","firstName":"Daikichi","middleName":"","lastName":"Ogawada","suffix":""},{"id":546450994,"identity":"0183abe2-65a1-4f2a-8888-9fec3339572c","order_by":4,"name":"Taikan Oki","email":"","orcid":"","institution":"School of Engineering, The University of Tokyo","correspondingAuthor":false,"prefix":"","firstName":"Taikan","middleName":"","lastName":"Oki","suffix":""}],"badges":[],"createdAt":"2025-11-14 14:42:17","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8116124/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8116124/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":107544900,"identity":"a55eef00-a917-48a7-ba24-4ba5ea345f2e","added_by":"auto","created_at":"2026-04-22 13:06:15","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":6167739,"visible":true,"origin":"","legend":"Article File","description":"","filename":"01.ManuscriptMainText.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8116124/v1_covered_2d58770e-a33c-4488-9b95-61c9f0870edf.pdf"},{"id":100767114,"identity":"4d6e040a-1c25-49a8-bed1-9ee763dab93c","added_by":"auto","created_at":"2026-01-21 09:08:05","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":10831606,"visible":true,"origin":"","legend":"Supplementary information for \u0026#x201C;Global assessment of how reservoirs and desalination plants enhance human water security","description":"","filename":"02.ManuscriptSupplementary.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8116124/v1/e2e2b6448053d13495183e6a.pdf"}],"financialInterests":"\u003cb\u003eYes\u003c/b\u003e there is potential Competing Interest.\nA.M., T. 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