Over the past decade, local municipalities have become much more cognizant of their sewage infrastructure and the adverse impacts that can occur when groundwater infiltrates this system. ALCOSAN, which processes waste water on behalf of Brentwood, is offering residents an opportunity to learn about what happens after they flush the toilet or drain the tub. The annual open house event will be held at their facility on September 17th from 9AM to 4PM. Visitors will have an opportunity to tour the treatment plant, partake in hand-on environmental exhibits, and learn about local ecology. Lunch will be provided. Free parking is available, and a no-cost shuttle will serve transit riders at the North Side T station.