Geophysical Survey at the CEC
Until recently, the space that is now the parking lot behind the Community Education Center (CEC) on Lancaster Avenue was home to at least seven residences, including some of the original West Philadelphia homes built in the 1840s. You can see the outlines of these houses in the image below, which overlays an 1895 map over a modern aerial photograph.
The CEC parking lot in 1895. (GPGN)
In the 1960s, the West Philadelphia Corporation used a variety of legal tactics and eventually bulldozers to remove residents and demolish the Black Bottom neighborhood. These destructive events and subsequent development of various high-rises suggest that almost nothing remains of the 19th and early 20th-century origins of the Black Bottom and its residents. However, the stability of the CEC building and surrounding grounds has acted as a buffer, making this parking lot one of the few if not only places in this part of West Philadelphia that could contain intact historic materials left behind by 1800s residents.
In February and March 2023, the Heritage West team worked with Dr. Chad Hill to conduct a geophysical survey of the parking lot and grounds surrounding the CEC building. Working with CEC permission, our primary goal was to use Ground-Penetrating Radar (GPR) and Electrical Resistivity (ER) to determine what evidence remained of the homes and yards that once lined Warren and Little Pine/35th St. Geophysical survey techniques allow us to look underground without excavation, providing a sometimes blurry but valuable perspective that can give us lots of important information and guide future excavation plans.
Dr. Chad Hill conducting geophysical survey in the CEC parking lot.
In this case, the GPR results, which can be seen in the image below, revealed a clear disturbance on the western portion of the parking lot. This is where the Warren brick rowhomes once stood and represents the edge of the demolition of the Black Bottom neighborhood in the 1960s. The red dotted lined on the image below represents where the bulldozers stopped, leaving a rubble pile of what were once brick rowhomes. Despite the violence of this destruction, you can still see faint vertical lines in the data, suggesting that some of the brick walls remain intact beneath the demolition debris.
The eastern side of the lot shows the foundations of two sets of twin homes (outlined in the image above with a green dotted line), constructed out of wood in the 1850s. Building A, in the lower right corner, has been partially intruded on by the 1960s rubble. We have been able to find a photograph of it still standing in 1961 (see below). Building B is better preserved, and you can see the filled in basement (the whiter rectangle in the far upper right corner), a probable small yard or porch (the black rectangle outlined in white just to the left of the basement), and a possible storage pit in the back yard. The fact that evidence of these structures still persists underground is exciting, as they were some of the earliest homes constructed in West Philadelphia. We will thus focus our upcoming excavation on these areas.
1961 photo showing ruins of an 1800s home behind today’s CEC building. (Philadelphia Department of Records)
About this post’s guest author:
Dr. Chad Hill’s is a Postdoctoral Fellow in Penn’s Department of Anthropology. His research focuses on the later prehistory of the Near East, with specializations in remote sensing, GIS, advanced image processing, and faunal analysis. He is the field director of the Galilee Prehistory Project, excavating Chalcolithic sites in the Galilee region of Israel, and co-Director of the Landscapes of the Dead project, using drones to monitor looting at Early Bronze age cemeteries in Jordan. As part of the Penn Paleoecology lab he is working on the Landcover 6k project, using archaeological, historical, and paleoenvironmental data to improve modern climate models.