Here is an example of one of the information panels they had on display:
The panel illustrates one step in the treatment process, the likely equivalent of aeration tanks like these at our Easterly plant in Cleveland where good bacteria feed on germs in the wastewater. The text, translated from German via Google, reads:
This pool is called a revival pool. Quite a lot of bacteria live here and these need lots of air to breathe. Therefore, air is constantly blown. Bacteria purify the water and eat the dirt."Revival pool." Great term.