Resumen: Reduced-order models (ROMs) based on the proper orthogonal decomposition have been proposed to reduce the computational resources required by the full-order models (FOMs) to approximate partial differential equations. In this paper a Roe-based ROM is developed to solve the shallow water equations in presence of source terms more efficiently than the Roe-based FOM. The well-balanced property and other numerical corrections such as the entropy fix and the wet–dry treatment are taken into account using augmented Riemann solvers to build the Roe-based FOM. In addition to this, a time averaging approach is necessary to develop the Roe-based ROM. This approach is validated by solving some cases and the computed solutions are compared with those ones of Lax–Friedrichs-based ROMs. It is also studied whether the ROM preserves or not the well-balancing, the entropy fix and the wet–dry treatment. Idioma: Inglés DOI: 10.1016/j.cma.2023.116038 Año: 2023 Publicado en: Computer Methods in Applied Mechanics and Engineering 410 (2023), 116038 [27 pp.] ISSN: 0045-7825 Financiación: info:eu-repo/grantAgreement/ES/DGA-FEDER/E24-17R Financiación: info:eu-repo/grantAgreement/ES/DGA-FEDER/T32-20R Financiación: info:eu-repo/grantAgreement/ES/MICINN-FEDER/PGC2018-094341-B-I00 Tipo y forma: Artículo (Versión definitiva) Área (Departamento): Área Matemática Aplicada (Dpto. Matemática Aplicada) Área (Departamento): Área Mecánica de Fluidos (Dpto. Ciencia Tecnol.Mater.Fl.)