The Black Hills region in South Dakota encompasses a landscape of profound cultural and spiritual significance for the Lakota Tribes (Oceti Sakowin). This project, funded by CIRES ESIIL and led by the Maka Sitomniya Working Group, is developing a data cube that aligns with Indigenous Data Sovereignty principles as established by Tribal Elders in the working group. This project is community- and Indigenous- led, with decisions shaped collectively and guided by a Council of Elders. Our methodology centers on creating a multidimensional array-based data cube that integrates geohydrologic datasets, including streamflow, precipitation, and groundwater levels, into a coherent, queryable framework. In alignment with ESIIL's commitment to open and collaborative science, the technical implementation uses open-source tools: Python libraries such as xarray for handling labeled multidimensional arrays, CyVerse for cloud-based storage and processing that upholds Tribal data sovereignty, and GitHub for version control and collaboration. This initiative directly supports the Oceti Sakowin's ongoing efforts toward co-management of the Black Hills, facilitating Tribal input over how data is accessed, interpreted, and used. By applying an Indigenous Data Governance framework, the project supports the working group's ability to draw on both Traditional Ecological Knowledge and western scientific datasets. This approach builds on successful models of community-based environmental monitoring that affirm the importance of local data ownership and self-determination. The resulting data cube is designed to support both technical and non-technical users, with intuitive data access and visualization tools that encourage broad community engagement. This project represents a critical step in integrating Earth data science with Indigenous knowledge systems, supporting Indigenous-led environmental stewardship, and demonstrating how technology can uphold Tribal priorities through collaborative data management.