Diagram showing heights of reservoirs, dams, standpipes &c, 1894
Plan for the Collection, Purification and Disposal of the Sewage of the City of Philadelphia, 1912
Schuylkill steamship excursions ad, 1852
New Plan of Philadelphia, John A. Paxton, 1811
PWD’s Lance Butler with an invasive flathead catfish
Jar of raw sewage before treatment, 2000