Technical Abstract: Water resources are under growing pressure globally, and in the face of projected climate change, uncertainty about precipitation frequency and intensity; evapotranspiration, runoff, and snowmelt poses severe societal challenges. Interdisciplinary environmental research across natural and social sciences to address challenges in water resource management will require comprehensive and long-term data. In the last two decades, progress in the study of information (informatics) and its manipulation via computer-based tools has stimulated the development of data systems in many natural resources disciplines. Such informatics systems provide data storage, access, visualization, perhaps with analysis/modeling tools, and download capacity. Application of database technology can overcome problems of fragmentation, inadequate documentation, and cumbersome manipulation of complex data. Data management was identified as a critical requirement for USDA¿s Conservation Effects Assessment Project (CEAP) which was established to quantify environmental effects of agricultural conservation practices. Although the USDA and the Agricultural Research Service (ARS) have conducted watershed research since early in the 20th century, the data have been managed and disseminated independently from each research location, greatly reducing accessibility and utility of these data for policy-relevant, multi-site analyses. To address these concerns, STEWARDS (Sustaining the Earth¿s Watersheds, Agricultural Research Data System) was developed to compile, document and provide access to data from loosely coupled ARS research watersheds. The paper identifies technological advances in data management, assesses key organizational challenges, and discusses the role of data management in a USDA watershed research initiative, the Conservation Effects Assessment Project.