2012 Annual Report 1a.Objectives (from AD-416): Principal focus of the CEAP Watershed Studies is to evaluate the effects and benefits of conservation practices at the watershed scale, in support of policy decisions and program implementation. 1b.Approach (from AD-416): The effects of conservation activities on water and soil quality will be assessed at the watershed scale using models such as ARS' Soil and Water Assessment Tool, in combination with ARS long-term watershed data sets, expertise, and resources. 3.Progress Report: In order to evaluate the effects of conservation practices on water quality over the united States and to assess differences among regions of the United States, it is necessary to have access to a data base which represents these regions. Over the past year, there has been a continual effort to further populate a watershed scale data base with the observations from all of the ARS watersheds. These data have been collected and also quality checked before final entry. Geographic Information System-based data are available for use by different researchers and are being utilized for various meta-analysis for the relationships between watershed characteristics and meteorological parameters which affect water quality.