Revealing the COVID uptick, the CDC said: 'Wastewater monitoring can detect viruses spreading from one person to another within a community earlier than clinical testing and before people who are sick go to their doctor or hospital. It can also detect infections without symptoms.
Wastewater can also serve to harbor/buffer colonies of bacterium and viruses. It's only useful if you monitor regularly for a very long time so random and seasonal variances can be accounted for.
Oh you and your facts. Shoo.