Over the last decade, increasing availability of web services for hydrology and climatology data has facilitated publication of reproducible scientific research in hydrological and climate studies. Such web services allow researchers to subset big databases and perform some common data processing operations on the server-side. However, implementing such services increases the technical complexity of code development as it requires sufficient understanding of their underlying protocols to generate valid queries and filters. HyRiver bridges this gap by providing a unified and simple Application Programming Interface (API) to web services that are based on three of the most commonly used protocols for geo-spatial/temporal data publication: REpresentational State Transfer (RESTful), Web Feature Services (WFS), and Web Map Services (WMS).