R packages (CRAN) for water engineering

USGS R package for long-term water-quality and streamflow trends — home of the WRTDS method.

The reference R implementation of SPEI and SPI from the index's own authors.

INRAE's GR rainfall-runoff models (GR4J family) plus CemaNeige snow, packaged for R.

The USGS R package for pulling NWIS and Water Quality Portal data — gauge records as tidy data frames.

Canadian government R package for streamflow analysis — trends, frequencies and summaries from HYDAT.

R workhorse for hydrological time series — aggregation, summaries and hydrologically-aware plots in a few calls.

R client for the UK National River Flow Archive — catalogue, gauged daily flows and catchment metadata.

Run and read EPA SWMM from R — model execution, results import and GIS conversion on CRAN.