Centre Square Engine House, ca. 1807
Bethlehem Water Works, 2011
Roman Aqueduct in Segovia, Spain
Norman Lofton inspects sewer at Ditman and Sheffield, 1987
Main Pumping Stations for Philadelphia Drinking Water
Thomas Run sewer outlet at Cobbs Creek
Thomas Run sewer outlet during construction
Frankford Creek: Sad History of an Urban Stream title page
Logan Demanding Flood Relief, 8/18/38
Sewer Demand Taken to City Hall, 7/25/32