Digging Deep: 50 Years of Preservation Archaeology in Pennsylvania

Excavation on Columbia Avenue in Philadelphia revealed a 4,000-year-old Native American site. More than 1,000 prehistoric artifacts were recovered, including stone tools, projectile points and fire-cracked rock related to cooking hearths.
Pennsylvania Department of Transportation, FHWA and AECOM

On a lovely morning in early autumn, I arrive at an old farm along the Susquehanna River to find Dr. Frank Vento in his natural element. That is to say, he is squatting down at the bottom of a backhoe trench some 8 feet deep, carefully examining the many layers of flood-deposited sediment left behind by the great river. Frank, recently retired from the faculty at Clarion University, is a geomorphologist, a geologist and archaeologist whose specialty is the formation of floodplains, terraces and other kinds of landforms by the interaction of climate, gravity, water, wind and sometimes humans. Frank is down there looking for something, and as I walk up to the edge of the trench, he finds it. “Ha! I knew it!”

He extracts a stone spearpoint from the wall of the trench, 3 feet or so below the ground surface, and hands it up to me. It has the distinctive spade shape of a type of point archaeologists call a Susquehanna broadspear. It was dropped there by its former owner roughly 3,000 years ago and then sealed in situ by centuries of flooding.

While Frank and I both chuckle at his act of predictive bravura, the discovery isn’t just dumb luck. Frank suspected the point might be right where he found it, thanks not only to his nearly 25 years of research conducted along the banks of Pennsylvania rivers but also 50 years of archaeology driven by the National Historic Preservation Act (NHPA).

Geomorphologist Frank Vento in the field.
Photo by Kurt Carr

A Revolution in Archaeology

The five decades that followed the passage of NHPA left a dramatic signature on the streets and landscape of Pennsylvania. It’s hard to miss. Countless restored theaters, graceful bridges, log houses, quaint Main Streets, iconic landscapes and famous sculptures owe their continued existence and restored glory to the effects of this landmark legislation (see “Before and After the Act: Historic Preservation in Pennsylvania,” Winter 2016). Beyond this dramatic and obvious evidence of heritage preservation is a mostly invisible legacy. It lies deep beneath our feet, under the pavement and the farm fields and the deep woods. You can’t see it, but it’s no less important, and in many cases it’s much, much older than our aboveground heritage. Fifty years of preservation archaeology has produced a picture of historic and ancient Pennsylvania that we barely imagined before NHPA.

In Pennsylvania, this hidden heritage is to a great extent the result of old rivers and old cities. The rivers of Middle Appalachia are among the oldest on earth and were more or less where they are now before the Appalachian chain rose some 225 million years ago. The floodplains that border these rivers have been growing by increments since the end of the Ice Ages, around 14,000 years ago. The layers of silt, sand and clay that the Susquehanna, Delaware and Monongahela rivers have left behind after periodic floods extend to depths of 20 feet or more in some places. Sealed within these flood deposits are the communities and encampments of Pennsylvania’s original residents. Successively older and deeper evidence of these First Nations – stone tools, pottery, cooking fires, storage and trash pits – is stacked within the floodplains. The result is a lengthy and complete record of their history beneath the fields and forests that line the banks of our rivers.

Likewise, 18th- and 19th-century cities like Philadelphia and Pittsburgh have expanded over the decades, not just out but up. Below the streets are the surprisingly well-preserved stories of their growth and evolution, under yards and tons of rubble, foundations and pavements. A busy city street can hide past industry, tenements, homes, farms and Native American settlements, lost worlds that until the last 50 years nobody even imagined were there.

The plan to widen U.S. 11/15 near Liverpool, Perry County, put Section 106 into effect, leading to the excavation in 1998-99 of the Wallis site. The State Museum of Pennsylvania

What revealed this unknown past was, for the most part, a surprisingly brief paragraph of NHPA: Section 106. This directive to federal agencies to deliberate on the results of their actions and provide for expert commentary underpins the many millions of dollars and the monumental accomplishments of much of America’s 20th-century efforts to preserve its own past. The regulations that implement Section 106 prescribe efforts to identify and evaluate historic properties and to avoid, minimize or mitigate damage that may be done to them by everything from dams and levees to highways and sewage treatment plants. For 50 years now, whenever the federal government spends money, builds infrastructure or issues permits, Section 106 ensures that historically significant places will receive some measure of consideration. Among the effects of the legislation was a revolution in archaeology. The provisions of NHPA produced more archaeological discovery and research than ever before in America. The last 50 years have yielded nothing short of a renaissance in the study, preservation and rehabilitation of the tangible past, including evidence buried deep beneath our feet.

Features such as this roasting pit were uncovered at the Wallis Site. The State Museum of Pennsylvania

On the Riverbank

“It’s not what you find, it’s what you find out.” – David Hurst Thomas, Curator, American Museum of Natural History

Since the late 1980s dozens of archaeological projects carried out in compliance with the provisions of Section 106 have allowed Frank Vento and other geomorphologists and archaeologists to study the floodplains and terraces of the Susquehanna, Delaware and Ohio river valleys. The result has been an advance in what we know about the history and formation of these broad riverine landscapes. As it happens, what look like big, flat corn and bean fields along the river to a casual observer are incredibly complex places, containing within themselves records of Pennsylvania’s climate history, hydrology and population growth.

These projects have defined a sequence of terraces that date from the middle Ice Age to the 19th century. They have encountered buried swamps and wetlands that have preserved all manner of organic material, from pollen and charcoal to waterlogged vegetation, that have in turn enabled precise reconstructions of now extinct or greatly changed ecosystems. They have produced a nearly complete record of flood events along the river, most of which occurred long before written records existed. These data play a valuable role in modern evaluations of Pennsylvania’s environment and climate, how they have changed, and how they are changing. They have also allowed us to reconstruct the world in which the first Pennsylvanians lived and adapted, how that environment affected them, and how they altered it.

Native American occupations through 10,000 years at the stratified Wallis Site.
Pennsylvania Department of Transportation

There are few places where that long record of life along Pennsylvania’s rivers can be seen and understood more clearly than a small section of floodplain tucked in next to U.S. Route 11/15 along the Susquehanna River near the small town of Liverpool in Perry County. This unassuming little place, now overgrown with silver maples, poison ivy and honeysuckle, was the scene of one of Pennsylvania’s most important archaeological projects during the mid-1990s. The work conducted there defined what is known to archaeologists as the Wallis Site, and it opened a window into the history of the Chesapeake’s largest tributary and the lives of some of Pennsylvania’s first residents.

When plans for the widening of U.S. 11/15 were developed, the federal funds earmarked for the project brought with them the requirement to comply with Section 106. The heritage preservation staff of the Pennsylvania Department of Transportation (PennDOT), in consultation with their colleagues at the Pennsylvania State Historic Preservation Office, recognized that the project would potentially affect many riverside historic buildings and districts, the traces of the old Pennsylvania Canal, and an unknown number of archaeological sites. Since the highway follows the Susquehanna closely as it winds between Duncannon, Perry County, northward to near the forks of the river at Selinsgrove, Snyder County, it was presumed that some of these sites would contain buried landscapes and evidence of prehistoric occupations. What was not expected was just how ancient some of that evidence would be.

At the Wallis Site, consulting archaeologists working for PennDOT encountered artifacts and features – nonportable evidence of occupation such as cooking hearths, storage and trash pits, and the small circular stains made by wooden posts known as post molds – left by successively older Native American cultures as their test excavations penetrated the more than 7-foot-deep floodplain. These chapters of Native American history included some stories familiar to most archaeologists in our region. There were pottery sherds and stone tools left by Late Woodland people who lived at the site around 800 years ago. Deeper, there were features and stone tools left by Transitional (c. 4,000 years old), Late Archaic (c. 5,000 years old) and Early Archaic (c. 8,000 years old) period hunter-gatherers. By the time the archaeologists had excavated through the last of the Archaic deposits, they thought the floodplain had finished its millennia-long tale, but as it happened, it held one more chapter.

Excavation at the Wallis Site. The State Museum of Pennsylvania

The ancestors of modern Native Americans entered North America from the Old World sometime during the Ice Ages. Excavations conducted over the last 20 to 30 years at places like Meadowcroft Rockshelter in Greene County and Cactus Hill in southeastern Virginia keep pushing that date earlier. Some sites have now dated to more than 22,000 years old. By 10,000 to 14,000 years ago, at the end of the last glacial advance, there were small bands of hunter-gatherer people living in what is now Pennsylvania. These people, known as Paleoindians to the archaeologists, had a very distinctive stone tool tradition that is as unmistakable as it is technologically impressive. Its primary expression is in fluted spearpoints, known as Clovis, after an archaeological site in eastern New Mexico. Clovis points feature a large flat flake scar, or flute, detached from the base to the middle of each side of the point. The flutes facilitate solid hafting of the tool in a wooden shaft and make it especially suitable for downing large game species. Fluted points can’t be mistaken for anything else in a North American archaeological site. Since the human population was very thin at that time, highly mobile, and organized into small extended-family bands, Paleoindian sites are the rarest and most poorly documented in the commonwealth and everywhere else in North America.

Paleoindian fluted spearpoints and a base excavated at the Wallis Site.
The State Museum of Pennsylvania

When the archaeologists found themselves at the very base of the floodplain at the Wallis Site, they encountered the cobbles, gravel and sand left behind by the melting Ice Age glaciers. Much to their amazement, there were also chips of flint and part of a cooking fire sitting directly on what would have been a Late Pleistocene cobble bar at the edge of the Susquehanna. Before long, a fluted point, one of five eventually found at the site, was encountered at the same level, along with a variety of scrapers, drills and other kinds of stone tools used for wood and bone working. They had stumbled upon part of an intact and sealed encampment left behind by a band of Paleoindian hunters, one of only a handful of such sites ever found in the Middle Atlantic region. By the time the excavations at the Wallis Site ended in 1999, several hundred square feet of this encampment were exposed and painstakingly mapped and excavated. Analysis of the results took six years and dated the encampment to approximately 10,000 years before the present. The archaeologists were also able to define exactly what the Paleoindian band who used the site were doing there. Their stone tools yielded evidence of the processing of fresh animal hides and bone. The part of the site discovered by the project appears to have been a riverside butchering location at the edge of a larger encampment located on higher ground to the west. The researchers were also able to surmise that much of this larger encampment was likely obliterated when the original highway was built in the 1940s and ’50s, before the passage of NHPA.

The excavation at Wallis greatly expanded what we know about these early Native Americans in Pennsylvania and provided an immense amount of information about their Archaic and Woodland descendants as well. Wallis remains the only site encountered with an intact Clovis occupation in the Susquehanna Valley, but dozens of other deeply buried Native American sites have been investigated along all of the state’s major rivers as a result of compliance with Section 106. At sites like City Island and Gould Island on the Susquehanna, Sandts Eddy on the Delaware, and Hunters Station on the Allegheny, human occupations sealed many feet below the ground have taught us much about the vanished worlds of Archaic and Woodland people, some of whom lived as long as 9,000 years ago. At all of these sites, NHPA has helped change and expand what we know about the antiquity and cultural history of our First Nation predecessors in Pennsylvania, about the history of our rivers and our climate, and in the end, about what it means to be human.

Underneath Our Feet

“In a city it’s impossible to forget we live in places raised and built over time itself. The past is underneath our feet.” – Esther Woolfson, Field Notes from a Hidden City

The area east of Interstate 95 that passes through the Fishtown section of Philadelphia is mostly industrial, a gritty 20th-century legacy of old factories and brownfields fronting the Delaware River. It’s not a terribly romantic or scenic landscape, but it has a secret, kept for centuries, that has been uncovered by compliance archaeology.

The excavation of the site of the Dyottville Glass Works in Philadelphia exposed foundations related to annealing ovens and the glass house structure, brick floors, and furnace cleaout tunnels, representing three identified building phases. The factory was first constructed in 1816 and remained in production through several owners until closing in 1908. Pennsylvania Department of Transportation, FHWA and AECOM

Archaeologists working ahead of the planned widening and improvement of I-95 have been conducting excavations there for the last several years, and what they found has helped redefine the history of one of the largest and oldest cities in the country. Buried deep beneath yards of rubble, concrete, trash and cinders they have encountered the perfectly preserved remains of some of the city’s early 19th-century industries, including a shipyard and a glass manufactory. They have exposed the yards of 18th- and 19th-century homes and businesses. They have even encountered the campsites of the pre-European inhabitants of what would be Philadelphia, the ancestors of the Lenape people who met and entered into a treaty with William Penn. This was a real surprise that challenged the perception that the industrialization of the Philadelphia landscape during the 19th and 20th centuries surely erased whatever was there before. As senior archaeologist for the I-95 project Doug Mooney noted about Philadelphia’s history, “Until this project, Native American people were never really part of the conversation. . . . Now that’s all changed!”

All of these old landscapes, with all they have to tell us about the history and prehistory of this great city, have revealed things about Philadelphia’s past that were long forgotten or that we never knew. They are a treasure trove as scientifically and historically significant in their way as a Southwestern pueblo or an Egyptian pyramid. Before this compliance archaeology project, the busy day-to-day life of modern Philadelphia went on at street level many feet above this hidden world. Nobody even knew it was there. Certainly no archaeologists went looking for it. Thanks to NHPA, this project and others that were done ahead of the Vine Street Expressway, the President’s House, and innumerable other urban archaeology projects in the city have revolutionized what we know about the early history, growth and development of Philadelphia and its environs. People whose names never appeared in the social registers, from Native American villagers and African slaves to immigrant factory workers, have come back to life and taken their place in the city’s rich and complicated heritage.

Political and military artifacts recovered from the ongoing archaeological excavations along I-95 in the Fishtown and Port Richmond sections of Philadelphia: top left, Tallio sleeve button (c. 1760-1810) and American artillery corps button (c. 1814-21); bottom left, transfer-printed pearlware teapot with Lafayette at Franklin’s tomb image (c. 1824-40); center, Henry Clay campaign slip-decorared redware dish (1844) and William Howard Taft inauguration button (1909); top right, George Washington glazed redware smoking pipe (c. 1844-61); bottom right, Zachary Taylor and George Washington aqua glass flasks, probably made at the Dyottville Glass Works (1860s).
Pennsylvania Department of Transportation, FHWA and AECOM

Similarly, in Pittsburgh, Harrisburg, Erie, Scranton, Wilkes-Barre and other smaller towns and cities across the commonwealth, hundreds of archaeological projects conducted in compliance with Section 106 have revolutionized what we know about the history of those places. Planned water and sewer lines at Point State Park in Pittsburgh allowed the discovery of portions of the deeply buried but still intact 18th- and 19th-century landscapes that lie below the Triangle. Archaeology conducted in advance of levee construction in towns like Wilkes-Barre and Lock Haven has exposed the remains of logging, coal mining and Native American settlements that preceded the modern cities. Excavations on Harrisburg’s City Island in the 1990s introduced thousands of area students to 18th- and 19th-century farmers and unknown generations of Native Americans who called the island home.

These detailed pictures of the urban past have helped guide the design and implementation of modern infrastructure and development and have filled in huge gaps of interpretation and understanding of our urban heritage. In a real sense, compliance archaeology has allowed the hidden past of Pennsylvania’s communities to inform their future.

Small bisque porcelain figurines like this serenading moon man made by the Schafer & Vater factory in Rudolstadt, Thuringia, Germany, were common mantle or shelf ornaments at the turn of the 19th century. This moon man was excavated along I-95 in Kensington.
Pennsylvania Department of Transportation, FHWA and AECOM

The Next Fifty Years

Understanding where Section 106 archaeology has taken us leads naturally to a consideration of where the next 50 years is going to take us. Trying to predict the future in a world where technological, political and other kinds of change whirl along at breathtaking speed is fraught with risk, but some things seem obvious.

The last decade in particular has brought a technological revolution in detecting, mapping and establishing the age of archaeological sites. Thanks to innovations like geographic information systems (GIS), light detection and ranging (LiDAR), ground penetrating radar (GPR), spectrographic analysis, 3-D scanning and printing, and innumerable other innovations, the movement and evolution of people, ideas and objects through time and across ancient landscapes has been traced rather precisely. The technology that allows us to see and analyze archaeological sites and data in new ways and through very narrow windows gets better and less expensive with each passing year. The young archaeologists being trained today grew up with this technology, and their facility for using it and adapting it to new kinds of data and situations is already a marvel and will only get better.

Most professional archaeologists (more than 90 percent) work in Section 106 compliance and resource management. In a profession that was profoundly white and male in the previous half-century, the likelihood is that the demographics of American archaeology will change. It is already doing so. As of this writing, women are outpacing men in enrollment in archaeology and anthropology graduate programs. Young and promising African American and Native American archaeologists are starting to make their mark in the profession and bringing a new, insightful and much needed perspective to their own heritage.

Finally, and perhaps most importantly, the way archaeologists will disseminate the results of their work is already changing rapidly. All of the results of the archaeology conducted for I-95 are available at the project website – one of the first large Section 106 projects in the country to report exclusively on the web. Research using online artifact catalogs, images, primary and secondary resources, and professional collaborations between archaeologists based not just in different cities but different continents are all now the norm. High-definition digital video available for instant download brings the results of Section 106 archaeology to everyone’s tablet or smartphone.

For most Pennsylvanians, and indeed for most Americans, it seems the word “archaeology” conjures up images of Egypt, or maybe Arizona. While the spectacular antiquities of those places have always captured the public imagination, they also serve to obscure something very important. You don’t have to go to Giza or Machu Picchu or Mesa Verde to find archaeology. Every place has a past, and every past is important. As the digital revolution makes the results of archaeology in the public interest more readily and easily accessible, more citizens will better understand where they and the communities they live in came from and who was there before them.

Archaeology’s great strength in the public mind is its ability to connect all of us directly and sometimes viscerally to our predecessors. A stone spearpoint, a fragment of pottery, a gunflint or a medicine bottle can connect each of us to another life lived long ago. There is great power in those connections. As more of what we’ve found beneath Pennsylvania’s landscape becomes available to every home and classroom in the state, we won’t have to worry quite so much about saving the past for the future. It will likely save itself.

For More Information

Kurt W. Carr and Roger W. Moeller’s book First Pennsylvanians (PHMC, 2015) presents the cultural evolution of Native Americans in Pennsylvania, from the Paleoindian period of 16,000 years ago to first contact with Europeans in 1500-1700, based on archaeology in the state, including the many projects made possible by NHPA.

A booklet in PennDOT’s Byways to the Past series, The Wallis Site: The Archaeology of a Susquehanna River Floodplain at Liverpool, Pennsylvania by Patricia E. Miller (2009), discusses the important role of that excavation in the archaeology of the Susquehanna Valley.

The Digging I-95 website summarizes the amazing range of sites, objects and information gleaned from the award-winning multiyear project.

A video initiative sponsored by the Register of Professional Archaeologists and part of the Preservation 50 celebration called the Making Archaeology Public Project has resulted in a series of individual state documentaries on the remarkable discoveries below all of our feet. Pennsylvania’s contribution can be viewed at MAPP – Digging Deep: Buried Landscapes of Pennsylvania.

Joe Baker is an archaeologist, writer and editor, currently at PennDOT’s central office. He has been working in this capacity at various times for three federal agencies and three state agencies since 1979. He has a BA from Penn State University and an MA from the University of Montana, both in anthropology.