National Research Program (NRP)
Exploration and Graphics for RivEr Trends (EGRET) is an R-package for the analysis of long-term changes in water quality and streamflow, including the water-quality method Weighted Regressions on Time, Discharge, and Season (WRTDS).
Visit the EGRET GitHub page for more information and for instructions on how to obtain the software.
The USGS Groundwater Age Mixtures and Contaminant Trends Tool can be used to explore the effects of basic aquifer properties and well configurations on groundwater age mixtures in groundwater discharge and on contaminant trends from varying nonpoint-source contaminant input scenarios. Visit the GAMACCT site for more information and to use the tool.
TracerLPM is an interactive Excel workbook program used to evaluate groundwater age distributions from environmental tracer data by using lumped parameter models (LPMs). User-defined age distributions, such as those determined from particle tracking, and those generated from LPMs can be used to calculate past and future concentrations of non-point source contaminants and in evaluating the response of wells or receptors to changes in source loading using TracerLPM. Visit the TracerLPM site for more information and to download the workbook.