These are Sharon’s unofficial visualizations of MWRA data monitoring wastewater for traces of the virus that causes Covid-19. For official versions, please visit the MWRA’s Web page with their graphs and the source data from Biobot Analytics.
In the first two graphs below, you can mouse over bars to see underlying data points, including estimated margins of error in the samples.
The last two graphs visualize the rate of change in the Covid samples by using the log values of the sample numbers as opposed to the actual numbers. (The New York Times explained back in March 2020 why log scales can be useful in tracking the course of a pandemic). Data start in 2021.