The objective of this report is to provide an update on the water quality conditions of the 5 EGA tributary sites and to evaluate the sampling program and results in terms of whether sufficient information is available to establish accumulated state. In addition, we provide specific recommendations for ongoing sampling based on the updated statistical results and potential future monitoring objectives. The 2012-2021 data set provides a greater number of samples (n=241) compared to the previous (n=72) analysis as well as an additional 8 years of sampling. Clear differences in mean concentrations observed between past and present timeframes highlights the importance of this increase in sample size and timeframe to characterizing the WQ at these sites. Summary of samples and allocation across years and seasons have been provided. Consistent open water sampling was achieved; however, winter sampling was a challenge for several sites. Except for the winter seasons at BI1 and MC1, all sites have within season sampling numbers that exceed the minimum values (8-10) suggested before any statistical test (USEPA, 2009). Summary statistics have been provided for all parameters (Appendix A), while investigation of other data characteristics was performed on a subset of representative parameters. Patterns in seasonality and data distribution characteristics were provided to better understand the natural variability inherent in these tributary basins which is important for the design of future monitoring programs. The power analysis revealed that, with a few exceptions, each parameter has sample numbers that allow for the detection of statistically significant results with 80% power. Finally, the cumulative mean and median graphs demonstrate that there have been sufficient samples collected across a range of 9 years, presumably with a range of water level conditions to establish current accumulated state. Several parameters appear to be showing increasing or decreasing trends, but this was not confirmed with statistical analyses.