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Penobscot Expedition Archaeological Project

In June 1779 the government of Great Britain dispatched a contingent of soldiers to Majabagaduce, Massachusetts (the present-day town of Castine, Maine) and established the military and political headquarters of a new colony for loyalist subjects fleeing rebellious American colonies in New England. The State of Massachusetts responded to the British invasion by organizing what was to become the largest combined military and naval operation conducted by the Americans during the War for Independence. On July 24, 1779 the American naval and land forces--known collectively as the Penobscot Expedition--entered Penobscot Bay and laid siege to the British fort. However, just as victory appeared to be within their grasp, the Americans were forced into a disorganized retreat up the Penobscot River by a British relief squadron that arrived at the entrance to the bay approximately one month later. The British vessels rapidly overtook the fleeing American forces, causing the latter to abandon and scuttle most of their ships to prevent their capture.

During the mid-1990s, Brent Phinney, the owner of a sawmill and steel fabrication shop in Brewer, Maine, discovered the remains of a wooden shipwreck in shallow water immediately off the Brewer (eastern) side of the Penobscot River. Shortly thereafter, he discovered a scatter of colonial-era cannon and other artifacts in the river just offshore of downtown Bangor. In June of 1998 Phinney contacted Dr. Warren Riess, Research Associate Professor of History and Marine Sciences, University of Maine (Darling Marine Center), to assist in recovering artifacts from these and other archaeological sites. Riess in turn contacted the Naval Historical Center's Underwater Archaeology Branch. Naval Historical Center representatives then met with state officials in Augusta to discuss Phinney's discoveries. Among other things, the meeting addressed the shipwreck site's preservation and protection, as well as the removal of artifacts. The mutual interests of the Navy and the State of Maine and their overlapping responsibilities for the Navy's ship and aircraft wrecks in Maine waters was also discussed.

Since 1999, the Underwater Archaeology Branch has conducted research in the Penobscot River as part of a multi-year cooperative effort with the University of Maine's Darling Marine Center and the Maine Historic Preservation Commission (MHPC) to research, investigate, and document shipwrecks and other submerged archaeological sites associated with the Penobscot Expedition of 1779. The submerged sites discovered by Brent Phinney were the subjects of the first phase of investigation. The remains of the wooden vessel (nicknamed the "Phinney Site") underwent a reconnaissance site investigation in 1999 and 2000. Preliminary analysis of data recovered during the 1999 field season led staff archaeologists to conclude that the Phinney Site represented the remains of a small eighteenth-century vessel that may have comprised one of the ill-fated American fleet that participated in the Penobscot Expedition of 1779.

Analysis of the vessel's remaining architecture indicates that it had a keel length of approximately 25.5 meters (83.7 feet), was constructed of a variety of American timber (predominantly white oak), and burned extensively prior to its loss. Specific hull characteristics, including the presence of radial cant frames in the bow, suggest that the vessel was constructed circa 1770. Attributes that point to a connection with the Penobscot Expedition include the presence amidships of two disabled 3 or 4-pounder cannon, as well as an extensive scatter of iron shot throughout the wreck site. Currently, not enough data exist to conclusively identify the vessel, although a number of the aforementioned characteristics closely match historic descriptions of the Continental Navy brig Diligent. The Underwater Archaeology Branch's research indicates that Diligent was constructed in Boston in 1776, had a length on deck of 88 feet, 5 ¾ inches, was armed with either 3 or 4-pounder cannon (depending on the source consulted), and was scuttled approximately two miles below the falls at Bangor (close to the Phinney Site's recorded location).

The artillery and munitions scatter (nicknamed the "Shoreline Site") was the subject of archaeological documentation and assessment in 2001. The Shoreline Site assemblage comprises Revolutionary War-era artifacts ranging from small ceramic fragments to complete pieces of iron artillery. Artillery associated with the site includes two 4 or 6-pounder cannon and one ½-pounder swivel gun. A large, diffuse scatter of colonial-era iron projectiles, including round, grape, case, bar, and half-bar shot, was found in close proximity to the cannon, as was a large iron conglomerate containing a variety of iron shot, fasteners, and scrap metal. Other artifacts observed at the Shoreline Site include glass bottle fragments, iron bar stock, and miscellaneous ferrous hardware. No wooden ship components were found in association with any of the artifacts, leading the Underwater Archaeology Branch to speculate that the Shoreline Site may represent a pile of munitions and artillery that was hastily discarded during the final hours of the American retreat upriver.

In September 2002 members of the Underwater Archaeology Branch initiated an intensive 10-day magnetometer survey along nine corridors of the Penobscot River. The 2002 survey was intended to locate the remains of at least ten American vessels, including the Continental Navy frigate Warren (the flagship of the American fleet), which was reportedly destroyed by its crew at Oak Point near the town of Winterport. The Underwater Archaeology Branch also attempted to pinpoint the wrecks of nine other smaller craft scuttled near Bangor. According to historical sources, most of the vessels that managed to reach Bangor were scuttled in the river immediately below the vicinity of the present-day falls (referred to as the "head of navigation" in numerous historical references), and were very close to one another when destroyed. Warren was apparently burnt at "Oak-Point Cove" (present-day Kempton Cove) after going hard aground during the American retreat.

Originally, the Underwater Archaeology Branch had planned to survey only two corridors of the river; however, cooperative weather conditions and extended workdays enabled staff archaeologists to plan and execute magnetometry of seven additional survey sections. Consequently, a large percentage of the navigable upper reaches of the Penobscot River have now been magnetically investigated. The survey identified approximately 700 localities, many of which exhibit magnetic signatures consistent with the size, duration, and complexity expected of historic shipwreck remains.

At the behest of Dr. Arthur Spiess (Maine State Archaeologist), the Underwater Archaeology Branch submitted a letter report to the MHPC describing the results of a remote-sensing survey conducted in a portion of the Penobscot River known as Dunnet's Cove. This section of the river, located along the western shore just south of the Bangor Harbormaster's dock complex, was to be impacted by the Maine Department of Environmental Protection (MDEP) as part of a proposed hazardous material cleanup and mitigation project. Dunnet's Cove lies well within the boundaries of a larger project area investigated by the Underwater Archaeology Branch in 2000 and 2002, and is believed to contain the remains of one or more Penobscot Expedition shipwrecks. Armed with information provided in the Underwater Archaeology Branch's letter report, the MHPC planned to oversee MDEP's activities and prevent damage or destruction of potential shipwreck sites during the mitigation process.


1995–1996 Brent Phinney locates the remains of a wooden shipwreck in the upper reaches of the Penobscot River while diving for sunken logs. Shortly thereafter, he discovers an artillery and artifact scatter across the river from the shipwreck site.
June 1998 Phinney notifies Dr. Warren Riess of the presence of the wreck and suggests that an archaeological recovery project be initiated; Riess in turn contacts the Naval Historical Center and apprises the Underwater Archaeology Branch representatives of the situation.
August 1999 Naval Historical Center staff members meet with officials from the state of Maine to discuss initiatives to protect and preserve both sites discovered by Phinney. The meeting also addresses management of U.S. Navy ship and aircraft wrecks in Maine waters.
August– September 1999 Members of the Underwater Archaeology Branch initiate a reconnaissance site investigation of the shipwreck site (Phinney Site), as well as a limited remote-sensing survey designed to analyze environmental conditions at the wreck site and the immediate surrounding area.
September 2000 The Underwater Archaeology Branch conducts limited excavation and detailed hull recordation of the Phinney Site, as well as a brief site reconnaissance of the Shoreline Site. In addition, staff archaeologists conduct a magnetometer survey in a limited corridor of the Penobscot River between the cities of Brewer and Bangor.
September 2001 The Underwater Archaeology Branch archaeologists evaluate the post-disturbance condition of the Phinney Site, thoroughly document the extent and state of preservation of exposed components of the Shoreline Site, and conduct a magnetometer and side-scan sonar survey along a section of the river near Winterport that historical sources indicate is the site of abandonment for the Penobscot Expedition shipwrecks Warren and Samuel.
September–October 2002 Members of the Underwater Archaeology Branch initiate a 10-day remote-sensing survey of nine corridors of the Penobscot River thought to contain Penobscot Expedition shipwrecks. Of particular interest to the Underwater Archaeology Branch are the remains of the Continental Navy frigate Warren. Archaeologists also attempt to locate the remains of another early naval vessel, the United States corvette Adams, scuttled by its own crew near the town of Hampden during the War of 1812. By the close of the survey, a large percentage of the navigable upper reaches of the Penobscot River have been magnetically investigated.
March 2003 The Maine Historic Preservation Commission requests that the Underwater Archaeology Branch submit a letter report to the Maine Department of Environmental Protection (MDEP) that outlines the results of the Underwater Archaeology Branch shipwreck surveys conducted at Dunnet's Cove (near Bangor) in 2000 and 2002. The riverbed in Dunnet's Cove is slated for MDEP-sponsored hazardous material cleanup and mitigation projects to remove large quantities of viscous coal tar that leaked into the cove from a nearby coal gasification plant.


Hunter, James W., III  
       2004  The Phinney Site: The Remains of an American Armed Vessel Scuttled During the Penobscot Expedition of 1779. The International Journal of Nautical Archaeology, Volume 33, Issue 1.
       2004  Unearthing a Forgotten Naval Defeat. Pull Together: Newsletter of the Naval Historical Foundation and the Naval Historical Center. Spring and summer edition.

Hunter, James W., III, and James S. Schmidt

       2003  The Penobscot Expedition Archaeological Project: Field Investigations 2000 and 2001. Naval Historical Center Underwater Archaeology Branch, Washington, D.C.
Hunter, James W., III, James S. Schmidt and Harry Pecorelli, III  
       2003  Archaeological Remote-Sensing Survey, Penobscot River, Penobscot County, Maine: Magnetic Analysis of Dunnet's Cove. Naval Historical Center Underwater Archaeology Branch, Washington, D.C.
Published: Wed Dec 02 12:12:15 EST 2020