This Surface-Water Quality-Assurance Plan documents the standards, policies, and procedures used by the U.S. Geological Survey's Washington District, Water Resources Discipline office, also known as the Washington Water Science Center, for activities related to the collection, processing, storage, analysis, and publication of surface-water data. This plan serves as a guide to all District personnel involved in surface-water data activities, and changes as the needs and requirements of the District and Discipline change. Regular updates to this Plan represent an integral part of the qualityassurance process. In the Washington District, direct oversight and responsibility by the hydrographer(s) assigned to a surface-water station, combined with team approaches in all work efforts, assure high-quality data, analyses, reviews, and reports for cooperating agencies and the public.