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Sinking of CSS Alabama

WASHINGTON DC 20374-5060

The Navy's Computerized Shipwreck Database Inventory: Unique Concerns and Issues in its Development and Use

by Barbara Voulgaris, Underwater Archaeology Branch

(Material contained herein is made available for the purpose of peer review and discussion and does not necessarily reflect the views of the Department of the Navy or the Department of Defense.)

The gulls glided low then landed swiftly atop the towering walls of the stone fort. They seemed to sense what was about to happen and, like sentries, watched intently from their perch. Shortly after 6 am on that late summer morning, the warship crossed the bar at flood tide. Under heavy gunfire from shore batteries and enemy warships, the vessel veered left to engage an enemy ship. Suddenly, the warship was rocked by a tremendous explosion, which violently pushed the vessel onto its side. It heeled over and sank rapidly taking its captain and most of its crew down with it.

Nearly 138 years later, the unfortunate Tecumseh is but one of the 3,043 shipwrecks contained in the Naval Historical Center's Shipwreck Database. Little did Admiral Farragut know all of the complex preservation issues that would later arise from those "damn torpedoes."

Most of us have some familiarity with many types of databases, from detailed descriptions of their contents, to their structure, purpose, and even the software and hardware used to design and run them. Although these are all important considerations in developing any database, rather, I will address several issues unique to the development and use of the U.S. Navy's Shipwreck Database.

These unique issues include: the legal requirements establishing the database; the different criteria and priorities used for inclusion, including special problems; the nomenclature developed to identify naval shipwrecks by time period and type; the disclosure of information in relation to the program's protection responsibilities; and how the database helps establish research priorities and allocate resources to specific time periods and geographic areas.

Legal Requirements Establishing the Database

Section 110 the National Historic Preservation Act tasks Federal agencies with inventorying and protecting their cultural resources. In response, the Navy's Naval Historical Center (NHC) initiated its underwater archaeology program in 1993. An initial priority of the program was to establish an inventory of all shipwrecks under U.S. Navy jurisdiction. The foundation of this database was built by merging the National Park Service's National Maritime Initiative database and an older incomplete Navy database. Since then, our inventory has grown to include more than 3,000 wrecks. Like most databases, it is a continual work in progress. It is however, being used as a cultural resource management tool for the identification, location, evaluation, nomination, and protection of historic naval properties. Additionally, it is being used to develop strategies and establish priorities for future research and project planning which I will discuss at the end of this paper.

Criteria and Priorities for Inclusion, and Special Problems

At first, the criteria and priorities for inclusion appeared straightforward; all submerged vessels owned or managed by the U.S. Navy. More specifically, naval vessels lost through war or peacetime operations in U.S. or foreign waters from the colonial-era to the present. This enormous time frame spans more than 283 years of naval history. World War II represents the largest number of wrecks (1,084), the second largest group, post WW-II present (740), and the third largest group of wrecks encompasses the Civil War-era (564).

Because the scope of this inventory is so broad, research and data gathering was prioritized by era and navy. Priority one was to include all U.S. Navy vessels, with a special emphasis on World War II and Civil War-era shipwrecks. If a vessel was owned, leased, or chartered by the Navy and described as sunk, wrecked, destroyed, burned, exploded, foundered, grounded, abandoned, lost, or with any other term implying a submerged wreck, it was included in the inventory. The second priority included all Confederate ships that are 100 % government- owned. These included not only naval vessels, but also state and army vessels. The third priority included foreign naval vessels in U.S. waters.

However, this is when criteria and priorities became less straightforward and more convoluted. As research intensified, Navy ownership and/or final disposition of many vessels became increasingly unclear. Regardless, it was decided that these vessels should be included in the inventory until jurisdiction and fate could be determined through further research. Such types of problematic criteria include the following:

These issues are very complex and continue to remain problematic with each of these areas embodying their own very unique dilemmas. One recent case illustrates just how complicated these issues can be when we received an inquiry from England about the wreck Ezra Weston, submerged in the waters off Exeter. The Chief Constable's office in Exeter was reviewing an application for an explosives certificate which involved the wreck and they inquired if it was still under U.S. jurisdiction. The Ezra Weston was a liberty ship and therefore under the jurisdiction of the U.S. Maritime Commission. However, the Navy did have an interest in the vessel because the ship's armament was probably Navy. Further complicating the matter, it was carrying cargo that belonged to the U.S. Army, and due to the potential historical and archaeological value, the U.S. National Park Service's consulting archaeologist would most likely also have an interest. That is four government agencies that potentially have an interest in this single wreck. That was more than enough for the chief constable to deny the explosives permit. And we haven't heard a thing from their office since. However, even though the ship was not Navy property, we decided to include the wreck in our inventory because it carried Navy property.


Developing a strategy that allowed for confusing and conflicting Navy nomenclature required creative thinking. In order to perform an accurate quantitative analysis of the data, consistency of terms was essential. For example, searching for the number of ironclad rams lost during the Civil War off the North Carolina coast in 1863 would be impossible without consistency.

Generally, nomenclature for types of U.S. Navy vessels is rather distinctive. For example, the terms frigate, ship-of-the-line, sloop-of-war, and ironclad, are indicative of different classes of 18th and 19th century warships that vary by tonnage, armament, and rigging. "Battleship," in conjunction with a hull number such as BB-1, indicates a 20th century warship. However, we found conflicting documentation when the same term referred to very different types of vessels. Sloop may mean a small, one-masted, fore-and aft-rigged sailing vessel, or a sloop-of-war. A steamer could refer to steam-powered vessels employed in any number of distinct naval activities such as tender, tug, or transport. The class designation YC referred to a coal barge in the 1920s, but in the 1930s, it was used for open-lighters. Also, different terms were used to refer to a single ship. The same vessel might be called a galley in one document and a gunboat in another. This could mean that it was a galley acquired by the Navy and converted to a gunboat, or it could refer to a specific class of warship built to a galley design. The same steam-powered frigate with screw propulsion may be called a screw steamer, frigate, or simply a warship in various documents.

Such problems were particularly evident in, although not exclusive to, 18th and 19th century vessels. This is due in part to less standardization in ship nomenclature, design, and function. While some of these earlier vessels were built specifically as warships and auxiliaries, many were commercial or private vessels altered for military use. A sailing vessel could be used as a whaler, or converted to a naval gunboat or transport. Many sidewheel steamers were transformed into casemated gunboats. And a vessel could be employed in any number of uses during its naval service. The same steamer could at various times be considered a packet boat, a transport, or a tug, and referred to as such in documentation.

Nomenclature for these early ships is derived from a combination of rig, hull design, propulsion, use, and naval-class descriptions. Often a single database field cannot adequately identify the vessel. To correct this problem, five different fields were developed to be used in conjunction with one another to gain a relatively clear description of ship type. For 18th and 19th century vessels, a distinction was made between those that were built as a specific class of naval warship or auxiliary, and those acquired by the Navy and converted to naval use. Eighteenth and 19th century ship types were defined by combining descriptions of class, hull type, mode of propulsion or armament configuration, such as screw frigate or ironclad ram.

Terms currently used in the database to identify vessel type are: the Sailing Navy (18th and 19th century); the Old Steam Navy (19th century); and the New Navy (late 19th century to present). These terms were collected from a variety of historical sources. Terms for Sailing Navy and New Navy are fairly consistent and are generally taken unmodified from sources. Steam Navy nomenclature is much more irregular, thus a simplified and synthesized vocabulary was developed for vessels of this era.

The Sailing Navy

Terms used to describe sailing vessels tend to distinguish a ship primarily by class, hull type, rigging, or employment. Terms should clarify whether the vessel was a specific class of warship or was acquired and converted for naval use. If it was an acquired vessel, hull type or rig was entered into the "vessel type" field and the ship's employment was entered into the "use at loss" field. If the vessel was a specific class of warship, and if the number of guns the vessel carried is known, then that number was included within the "class" field.

The Old Steam Navy

Ships of the steam navy can be divided into two major categories: armored and unarmored, and a third for miscellaneous vessels. Terms indicating armored vessels describe major distinguishing visual elements of a ship's armor, hull design, or armament. Terms for unarmored steam vessels indicate class of warship or hull design, and mode of propulsion.

Nomenclature for 19th century armored vessels is varied and inconsistent. Therefore, instead of deriving terms directly from documentation, as with the sailing vessels, synthesized and simplified terminology was developed specifically for the database. The terms are broken down into three general categories that include: ironclads, monitors, and other types of armor. Within each category, there are several design variations. These terms adequately describe most 19th century armored vessels and are entered into the "vessel type" field. The employment of armored vessels as warships or gunboats is implied, and therefore, the ship's duty should be entered into the "use at loss" field (ex: vessel type: ironclad ram, use at loss: blockade duty).

The New Navy

Vessel types after 1920 are arranged into the following groups that include: warships; mine vessels; patrol vessels; landing vessels; auxiliaries; district craft; airships; Coast Guard vessels; and miscellaneous nomenclature. The class designation appears in the first column and is entered in the hull number field along with the vessel number (ex: AC-36). The vessel type, entered in the "vessel type" field, is listed in the second column along with any guidance or special information. Generally, the years in which the designation and vessel type were in use is given along with any changes that may have occurred. These terms are derived from the standard nomenclature published in the Naval Vessel Register.

Disclosure Policy

Although the database is still in draft format and many records are far from complete, it does contain valuable information regarding the location and character of shipwrecks. The release of specific location data, and information about a wreck's cargo, the existence of armaments, or knowledge of grave sites, could endanger wreck sites by exposing them to non- professional recovery techniques, looters, or treasure hunters, thus undermining the NHC's preservation responsibilities. Although no laws specifically protect the location or character of U.S. Navy wrecks, there are various statutes, regulations, and interpretative guidelines that address management and preservation of historical and archaeological sites that are applicable to naval shipwrecks.

Section 304(a)(2) of the NHPA (with 1992 amendments) provides the NHC the authority to withhold from disclosure the location of their historic resources if is determined that release of this information would risk harm to the resource. Therefore, no specific location information, information identifying cargo, armaments, or knowledge of grave sites is currently being released. In the case of Freedom of Information Act (FOIA) requests, this information is protected under 32 CFR 701.25 Exemption 3: Limited by Statute.

Shipwreck information derived from the database will be released upon approval of a written request by the Underwater Archaeologist, or other central authority at the NHC. Information released depends upon the requestor's status as a preservation professional and his or her purpose. In releasing data to other state and/or federal agencies engaged in similar tasks, the NHC can provide specific location and other data otherwise restricted. However, the requesting agency must agree not to release this data to the public or to any other agency without prior written approval from the NHC.

This policy was tested in September 1995 when the NHC received a Freedom of Information Act Request for copies of all materials it generated regarding the confederate submarine H.L. Hunley, recently found off the South Carolina coast. The NHC provided everything requested except documents that contained any references to the location of Hunley, home telephone numbers, and information that was considered predecisional in that it constituted internal advice, recommendations, and/or subjective evaluations.

Research Priorities

By conducting a quantitative analysis of wrecks by state and era, we've developed a list of research priorities. By far, Virginia has the largest number of Civil-war era wrecks. We have asked for Legacy resources to develop a partnership with that state as well as resources to continue our partnerships with Maryland, Vermont, and South Carolina. Based on information from the database, we are then able to select which resources are most important to survey first, based on their historical significance, and/or if the resource is threatened by human or environmental actions.

Another priority includes the Aircraft Wrecksite Database inventory. This inventory began at approximately the same time that the shipwreck database did, however it is nowhere as complete and comes with its own set of unique difficulties. The project is immense in that there are approximately 30,000 accident reports on file in Naval Aviation History and each report must be studied to determine if the plane was actually lost. It is estimated that this database will eventually hold more than 25,000 aircraft wrecks. As we near the next century, we would like to concentrate on those wrecks where there is very little archival information such as vessels from the colonial period and the War of 1812. As our databases continue to become more complete, the Navy's underwater archeology program continues to make strides in protecting its historic resources and helping to shed new light on our nation's rich maritime history.

25 May 2001