Maritime Heritage: Archaeological Survey at Rodanthe

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Capture of USS Fanny (Frank Leslie’s Illustrated Newspaper, 1861)

What is Maritime Heritage?

For much of human existence, people have relied on water as a source of food, energy, transportation, and even recreation.  A narrative of human interaction with bodies of water throughout the course of history are preserved not only in writing, but also in physical objects left behind.  These objects, sometimes referred to as material culture by archaeologists, can relay information about the culture of the people that made and used these objects; they can tell us something about ourselves and our shared heritage.  Although we have written records that help inform us of our past, these are often incomplete.  Archaeologists help plug some of the gaps by studying the material cultural remains for clues about their use, value, and meaning.  Maritime heritage is the study of our past in the context of marine environments.  It is about how we used, worked, traveled, and played in, on, and under water.

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Herman Moll Map, 1746

Why is it important?

Knowing where we come from and where we have been can help inform us of where we are going.  The study of history and of people in the context of the maritime world can also offers some advantages.  Objects that are submerged (found underwater) can sometimes be in an exceptional state of preservation.  Despite the passage of years, decades, and even centuries, some objects found beneath the waves look much like they did when they were first lost.  The better the state of preservation, the more an archaeologist is capable of extracting information from the object.

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John Lawson map, 1709

People relied on ships, boats, ferries, flats, and barges to carry cargo, livestock, passengers, and personal belongings.  We hunted whales and walruses, sharks and skates.  We used ships to cross oceans, to find new lands, to explore and interact with new cultures and we used them for war.  Sometimes these varied crafts did not reach their destination.  Bad weather, poor directions, leaky planks, hidden shoals, big waves and shallow water, cloudy skies and sudden squalls could sink a boat and often did.  These vessels went down with all that they contained still in their hold and could sit for centuries before they are rediscovered.  An archaeological study of a shipwreck is a study of culture in a confined space, a microcosm of a larger society.  Not only are the objects found on the vessel helpful and worthy of study, but the ship itself reflects cultural adaptations, innovations and technological advancements.

Additionally, in light of planned or future development, looking for submerged cultural resources is important because finding them may lead to the avoidance of damage to them.  In many cases, knowing where cultural resources (whether significant or insignificant) will also allow for actions to be taken that may avoid damage to construction equipment.  In the case of dredging, for example — a shipwreck may be damaged by a dredge — but it is also possible for the shipwreck to damage the dredge itself.  This would be the case for many other types of manufactured objects that may be submerged or buried in an area.  For this reason, spending money to assess an area for historical resources as well as marine debris may be a cost-saving in the end.

These submerged artifacts are resources to researchers and can be a source of information to help us answer questions we have about our past.  Like some natural resources, these maritime artifacts are finite and in need of protection.  Once the context of an archaeological site is destroyed, there is no reassembling it and the information that it can offer is severely diminished if not lost forever.

 

Maritime Heritage Survey

Archaeologists at UNC Coastal Studies Institute, instead of focusing their efforts on shipwrecks alone, approached this project with a broad consideration of the ways that humans may have impacted this area over time.  This expansive view gave way to a focus featuring four categories of research which included: 1) impacts from dredging, 2) impacts from commerce, 3) impacts from conflict, and 4) impacts from marine accidents.  By doing so, researchers hoped that these areas could highlight potential archaeological sites or give context to archaeological finds in the event of their discovery.  In addition, this approach afforded researchers the opportunity to divulge the history of an area that has never been the subject of an extensive historical investigation.

 

Methodology

 STEP 1: Historical Research

This project, like any thorough and proper archaeological survey, began in the archives where researchers accessed documents, records, letters, wreck reports and other historical information to carefully comb for clues.  Starting with the general and narrowing to the specific, researchers began first with regional histories found in secondary sources and whittled down to wreck reports of first-hand accounts recorded by the United States Life-Saving Service at Chicamacomico.  In consulting a broad array of sources, researchers could contextualize the fluid economic and social conditions that occurred in the larger landscape in order to see if similar activities took place in the Rodanthe research area and provide potential archaeological site locations within that boundary.

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Researchers examine a digital map featuring the research area.

 Step 2: Historic Maps and Geographical Information System

Due to the dynamic nature of the shifting sand banks on the coast, cartographic sources, such as historic maps, illustrate the hazards encountered by contemporaries of various times in history.  By identifying hazards, archaeologists can potentially pinpoint significant areas of risk where mariners may have run into trouble navigating.  Additionally, by comparing maps throughout history, researchers can examine shoreline change through time which may have impacted archaeological remains.  A landscape in flux means that which was once underwater could now be found on land and that which was high and dry may now be resting beneath the sound. Geographical Information System (GIS) is a computer software that researchers use as a tool to overlay these maps on top of one another for comparison.  The process by which these maps are overlaid relies on selecting specific points on the historic map that line up with a modern base-map.  In addition, examining these maps also showcases changing cartographic symbols within the research area, which reveals clues to wrecking events and evolving landscape use.  This preliminary research that occurs before archaeologists even enter the field is crucial to maximizing the productivity of the field survey.

Step 3: Side Scan Sonar and Magnetometer Survey

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A research vessel tows remote sensing equipment near Rodanthe.

Maritime archaeologist rely on remote sensing technology to cover large swaths of submerged areas in a methodical and systematic survey.  For this project, archaeologists utilized two different remote sensing technologies simultaneously to gain a greater sense of what physically remains on the sound floor or a few meters beneath it.  Side scan sonar emits sound waves in the form of a Compressed High Intensity Radar Pulse or CHIRP, which bounces off the underwater floor and returns to the receiver.  Any objects that sit off the bottom appear on a computer screen aboard the research vessel in the form resembling relief. It is up to the team of archaeologists to interpret these images and ascertain significance and sites of potential interest.  Researchers also used a magnetometer in concert with side scan sonar to aid in the survey process.  A magnetometer detects distortions in the earth’s magnetic field, which is useful because objects that are capable of distorting the earth’s field are ferrous, meaning they contain iron.  The presence of iron often indicates objects that were constructed by humans such as ships, docks, piers, and duck blinds.  Magnetometers offer the added benefit of detecting ferrous objects buried beneath the sand, providing the opportunity for anomalies or areas of interest not picked up by the side scan sonar.  The survey covered an area of 2.5 kilometers by 2.5 kilometers of sound floor.  To cover that much ground in an efficient and exacting manner, the researchers designed a line spacing grid that allowed for 200% coverage of the sound floor.  This meant that each square meter of the sound, within the research area, was remotely surveyed from two perspectives.  To carry out the survey, researchers performed what is commonly known as “mowing the lawn”.  Beginning at a Global Positioning System (GPS) fixed point, researchers set a heading and follow that heading for 2.5 kilometers.  When they reach the end of the survey area, they position the research vessel over 25 meters to begin another lane, heading in the opposite direction in which they just came, much in the same manner you cut the grass in your yard.  The work is not over upon completion of the survey portion of the project, in many ways it has just begun.  Archaeologists need to assemble the data and perform a set of procedures called post-processing.  This is an opportunity to refine the data and identify anomalies or objects of particular interest.

Step 4: Shoreline Transect Survey and Metal Detection

Al view of the emergency ferry terminal looking east.

In areas too close to shore where the remote sensing equipment could not go, the team performed a shoreline transect survey.  This portion of the research was not designed to be a comprehensive survey covering the entire shoreline, but rather just a sample.  The team established a survey grid comprised of a 600 foot by 600-foot section once again defined by GPS units.  In the event of an archaeological find, the researchers could pinpoint its location within the grid with an excellent degree of accuracy.  The team laid a baseline measuring 300 feet long and ran it on a direct northerly course to help construct their grid.  The process by which the team surveyed this sample area followed the same principle as the remote sensing, except this survey was a visual inspection, meaning they “mowed the lawn” using sight rather than equipment because the water depth allowed it.  When the visibility became poor, sense of touch took its place.  When the water became too deep, the archaeologists donned masks and snorkels.  During the shoreline transect survey, as team members conducted visual inspections, one of the members carried a metal detector.  This waterproof device, unlike the magnetometer, is capable of detecting other non-ferrous metals, while also collecting GPS positions for each anomaly.

Step 5: Photogrammetry

As the last stage of fieldwork, researchers created a photogrammetric model of a shipwreck found within the research area.  The shipwreck, known as Pappy Lane Wreck or officially as PAS 0001, is located in roughly three feet of water and is a known kayak destination for area recreationists.  Archaeologists, as well as other researchers, utilize photogrammetry and photogrammetric models in a number of ways to help conduct their research.  In addition to providing accurate measurements of the subject, they allow researchers to explore a site more in depth in the comfort of their office rather than the field, where conditions are variable and time is limited.  They also provide excellent baseline data for monitoring purposes.  A 3D model of a site can be used to accurately compare how the site is holding up over time and whether or not any major changes to the overall structure has occurred.

An aerial photograph of Pappy’s Lane Wreck off Rodanthe.

To make a photogrammetric model you need a camera, computer, and specially designed software to process the data into a three-dimensional representation.  Some smartphones today offer apps that allow users to take photographs of an object, which can then be made into a 3D model all on the phone.  At the UNC Coastal Studies Institute, researchers deployed a drone with a camera on it to collect high-resolution orthographic photographs.  With a predetermined flight plan uploaded, the drone followed a tight series of transects roughly 33 to 66 feet above the wreck taking photographs along the dimensions of the vessel.

A predetermined flight plan created for the drone prior to launch.

Researchers then uploaded the nearly two-hundred high-resolution photographs, each tagged with a GPS coordinated location, into 3D modeling software to create the model.  This processes the data and aligns the images, creating first a dense point cloud, and eventually a high-resolution multi-image photogrammetric model as seen below.

 

 

 

An Assessment of Cultural Impacts

The sound-side area of Rodanthe is like many parts of the Outer Banks, obscured from much of written history. It lacks the intrigue of the Lost Colonists of Roanoke, the divisiveness of the Battle of the Atlantic of World War II, and the heroism of the U.S. Life-Saving Service.  In fact, the only reason any written history relating to the vicinity survived at all is due in large part to the surfmen at the U.S. Life-Saving Station of Chicamacomico, which kept a record of the stricken vessels on both sides of the ‘Banks.  Historians refer to this area as a peripheral location; a place, although connected to the exploration, commerce, and settlement of the area, which never quite made its way onto the pages of history.  This does not mean that nothing happened here, it just means that that the historical archaeologist has their work cut out for them.

According to research collected during the writing of this report, the area of north Hatteras Island, including what was known as Chicamacomico Banks, Kinakeet Banks, and Hatteras Banks, became inhabited by non-native settlers in the early to mid-eighteenth century, although no one knows for sure exactly when.  These individuals invariably relied on the water for crabs, oysters, fish, and fowl, while they also planted and grew vegetables and corn, even building windmills to grind their grains.  A map revealing the locations of windmill sites throughout the Outer Banks supports that one was located in the area of Rodanthe as early as 1850 and even acted as an important landmark during the American Civil War.  An 1850 census places the population of Chicamacomico Banks at just over 200 individuals, which notable Outer Banks historian, David Stick, believed ballooned to 1,200 by the time of the Civil War.  These hearty inhabitants made do with what little they could grow, attaining sustenance in the form of food from the sea, but also securing goods and supplies that washed up on their shores.  By the beginning of the 20th century, commercial fishing came to dominate the area with fish houses cropping up along the sound shoreline.  Evidence of commercial life in the area is hard to come by as too little remains of which to inform historians except for reports from the Chicamacomico Life-Saving Station.

Map showing approximate positions of wrecking events in the research area according to historical sources.

The focus of this project was an area submerged beneath the Pamlico Sound, naturally, researchers looked to Life-Saving wreck reports for clues as to possible archaeological remains.  In addition, they consulted government reports put out by the U.S. Army Corps of Engineers, the U.S. Department of Commerce, and the U.S. Department of Treasury, as well as historical newspapers, to not only learn of the vessels stricken in the area, but also of their subsequent fate.  Surfmen from Chicamacomico, in some cases, were able to assist vessels that ran aground and refloat them, a detail not always present in their reports.  Marine insurance registers, as well as the Annual List of Merchant Vessels of the United States, provided additional information regarding the histories of some of these vessels.  After careful combing, the archaeologists compiled a list of thirteen candidates involved in marine accidents and incidents within the research area.  In almost all cases, the vessels were eventually refloated, but there remained the possibility that material culture or pieces of the vessels themselves may have been deposited on the sound floor during the wrecking event, which could be detected during a survey.  Project participants compiled dossiers on each of the thirteen marine incidents and utilizing this information approximated the relative position of the wrecks on a geo-rectified map.  This information is necessary for the interpretation of magnetometer and side scan sonar data.

An unidentified site of interest to archaeologist prior to the investigation was the underwater battlefield of a Civil War engagement that was later determined to be the first capture of an armed vessel in the war.  The U.S. army steam tug Fanny, transporting men and supplies north from Hatteras, came under attack within the sound by Chicamacomico in early October of 1861.  According to reports, soldiers committed some 30 cases of ammunition to the sound waters before running the tug aground and making their escape.  Whether or not these cases were ever retrieved is unknown, so there was a real possibility that they could turn up in the study area.

 

Results of Fieldwork

SIDE SCAN SONAR

To achieve 100% coverage using side scan sonar a researcher has to make a single pass over an area.  This study covered 4.2 square kilometers within the research area with 100% coverage.  To achieve 200% coverage an area must be insonified from two perspectives,

Side scan sonar data revealing an object, most likely a crab pot, on the sound floor.

which means that the researchers made a pass over an area from one angle and second pass from a different angle.  For a smaller portion of this survey, researchers attained 300% coverage in a section measuring 242,106 square meters by surveying this section from three perspectives.  This thoroughness ensured that any potential sonar target would be detected and the research area completely inspected.

Initially, 89 targets were classified and described, which were narrowed to 75 following duplicate deletion.  These targets were split up into four categories – pilings (extant and remnant), crab pots, a channel buoy, and unidentified features, with many of the unidentified features likely to be crab pots and natural debris like tree limbs.  Researchers did not discover any large structure which could possibly be identified as a shipwreck within the research area.

MAGNETOMETER

The magnetometer survey revealed small isolated magnetics spikes randomly dispersed throughout the survey area, with no collection of significant targets located.  Of the identified side scan sonar targets, 17 were found to have magnetic signatures which suggested to researchers that these were most likely crab pots.  Like the side scan data, nothing of significant size suggesting the existence of s shipwreck was discovered in the research area.

Map of research area with magnetometer data. Inset reveals close-up of an anomaly.

SHORELINE TRANSECT SURVEY AND METAL DETECTION

This survey turned up a few modern artifacts similar to those found elsewhere in the survey area such as crab pots, a cinder block, and contemporary building timber.  None of the anomalies detected with the metal detector were ground truthed, but suggest refuse lost or left behind by individuals who frequent the area for recreational pursuits.

PHOTOGRAMMETRY

The photogrammetric data collected on Pappy’s Lane Wreck proved useful for further investigation of the still unidentified vessel.  This data will be used to compare the present-day wreckage with photographs from 1970s, 1980s and early 2000s in an attempt to understand the degradation properties of the site and predict potential future environmental impacts to the hull.  Additionally, the 3D model contributes to future and ongoing archaeological work.  For example, a comparison of hull features can be made with builder’s plans when and if they are discovered to the model.

 

FURTHER RESEARCH

Although the archaeological survey at Rodanthe is complete and results revealed the paucity of archaeologically significant material within the research area, work remains to be done on Pappy’s Lane.  This fall, graduate students from East Carolina University’s Program in Maritime Studies, led by ECU professor and UNC CSI Maritime Heritage Program Head, Nathan Richards, Ph.D., will conduct an intensive investigation and archaeological Phase II excavation of the site in an attempt to extract empirically verifiable data that could aid in the successful identification of the wreck and shed light on its historical significance.  More information will be provided through this website as the project develops, so make sure to check back for updates.

“Shipwreck of Rodanthe, Pamlico Sound, 10 November 1988″ by Drew Wilson (Source, Drew Wilson Collection, Box 21, Outer Banks History Center, Manteo)”