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The Bureau of Land Management (BLM), in collaboration with the U.S. Environmental Protection Agency (EPA), is conducting its first Western Rivers and Streams Assessment (WRSA), a survey of the condition of BLM streams and rivers throughout the contiguous western U.S. The objective of the WRSA is to generate unbiased, quantitative estimates of baseline conditions from which regional and national aquatic priorities can be established and future conditions compared. The BLM is partnering with the EPA to intensify the National Rivers and Streams Assessment (NRSA) design on BLM lands, and implement sampling of perennial streams and rivers to accomplish this task. In this partnership, BLM is using a comparable survey design and field methods and indicators as are the EPA and State. This level of partnership maximizes the use of the generated data and makes best use of taxpayer resources available for monitoring. The WRSA is a component of the BLM's Assessment, Inventory and Monitoring (AIM) strategy designed to standardize data collection and facilitate science-based decision making on public lands. The WRSA will answer three central questions: 1. What percentage of BLM's streams and rivers are in good, fair or poor biological condition; 2. What is the linear extent of streams and rivers experiencing stressors such as excessive nutrients, high salinity, excess fine sediments and invasive invertebrates; and 3. What is the risk posed by the observed stressors to biological condition? To answer these questions, the BLM will sample approximately 300 statistically representative sites between 2013 and 2015, in collaboration with the EPA and western states. In this presentation, we will share preliminary results on the chemical, physical and biological condition of BLM streams and rivers, the first-ever statistically valid estimates of aquatic resources managed by the BLM.