Samples of sewage taken from a treatment plant that serves the Boston region indicate the presence of COVID-19 has increased sharply for all but a few samples over the past month.
Wastewater samples are taken multiple times each week at the Deer Island Treatment Plant and analyzed by the Massachusetts Water Resources Authority’s contracted laboratory, Biobot Analytics. The lab looks for viral RNA in the sewage samples and returns results in copies per milliliter.
A chart of the seven-sample average for both the southern and northern regions shows an upward trend that began in mid-October. With the exception of a dip at the end of October, the average copies per milliliter has climbed for both regions.