This data release contains the watershed ancillary data that were used as input for a set of dynamic Spatially Referenced Regression On Watershed attributes (SPARROW) models for watersheds draining to Puget Sound and the Strait of Juan de Fuca, Washington for the years 2005 - 2020. The SPARROW models were used to estimate mean seasonal total nitrogen and total phosphorous conditions and the delivery of those nutrients to Puget Sound and the Strait of Juan de Fuca. The data sets in each child item, which consists of a collection of CSV files, represents landscape conditions in the incremental catchments that made up the hydrologic network used in the SPARROW modeling. The conditions for catchments that were partially or fully outside the domain of the original landscape data were estimated by extrapolating the conditions from nearby catchments.