Multidimensional models and their measures regarding different dimensions are powerful instruments for decision makers. An ontology, in its basic expression as RDF, represents the reality from relationships between classes, and it is the base for linked data of the semantic Web. This work provides a basic methodology to obtain an ontology RDF from a multidimensional model of a data warehouse, capable to be aligned to other ontology of the Sustainable Developments Goals. Specifically, an approaching of alignment with the Sustainable Development Goals Interface Ontology [SDGIO] emerging by the United Nations Environmental Program [UNEP] is included. This methodology labeled as DW2RDF4SDG is instrumented for the SDG 6, aimed to ensure availability and sustainable management of water and sanitation for all.