StreamCat Application Programming Interface (API) and StreamCatTools R Package

StreamCat is a centralized dataset of watershed characteristics built to assist researchers and managers in sustainability of our Nation’s waters.  StreamCat is a published dataset characterizing the watershed features of ~2.65 million stream segments within the conterminous U.S.  The StreamCat dataset is built on the framework of the National Hydrography Dataset Plus Version 2 (NHDPlusV2).  Over 200 landscape metrics are summarized for every NHDPlusV2 catchment (i.e., the immediate landscape draining directly into a stream segment) and full upstream watersheds (i.e., the local catchment and all upstream catchments). The StreamCat data has been published as comma-separated value files on an FTP (file transfer protocol) server, but we have now developed an API (application programming interface) for StreamCat that allows simple, modern, and integrated data delivery for the StreamCat data.  Additionally, we’ve built an R programming library to leverage this API for easy integration of StreamCat data in the R programming environment.

Impact/Purpose

StreamCat strengthens the EPA’s ability to estimate and map the integrity and sustainability of our Nation’s waters by providing consistent and complete watershed characteristics for all flowing waters in the contiguous U.S. as represented in the National Hydrography Dataset Plus Version 2 (NHDPlusV2).  StreamCat data are used extensively throughout the EPA, by states and non-profits, and to develop national maps of aquatic condition and watershed integrity, and can be used to model and predict reference condition for the EPA’s National Rivers and Streams Assessment (NRSA. By providing  StreamCat data in a modern format that allows easy integration of data into models and applications through our development of an API (application programming interface), as well as an R package that leverages this API in the R programming environment, we are greatly enhancing the usability of the StreamCat data for the numerous applications and agencies using this valuable dataset.

Citation

Weber, M., A. Brookes, D. Rebhuhn, J. Peters, Ryan A Hill, AND S. Leibowitz. StreamCat Application Programming Interface (API) and StreamCatTools R Package. U.S. Environmental Protection Agency, Washington, DC, 2022.

• https://www.epa.gov/national-aquatic-resource-surveys/streamcat-metrics-rest-api