Iroquoise Project

 Iroquoise Project 

Carleton Island Project

Project Background

In the mid 1970's, the New York State Diver's Association worked under a New York State permit to excavate a shipwreck in North Bay Carleton Island in the St. Lawrence River near Cape Vincent, NY. Carleton Island was a British shipyard and shipment terminal occupied only during the American Revolutionary War. It was the supply post on the North East End of Lake Ontario where goods were transferred from small river bateaux on to lake sailing vessels. Two volunteer divers/researchers on the project, Dennis McCarthy and Michael Hughes of Syracuse, became interested in trying to identify the wreck in North Bay by the process of eliminating vessels that would have existed at the time Carleton Island was operational. 

"Iroquoise" British Library

In searching primary documents in the Canadian National Archives, Michael Hughes discovered a court of inquiry of a shipwreck in 1761. This court of inquiry was of the British vessel
Anson that had been "cast away" on an unknown ledge of rocks in the St. Lawrence River. By comparing information from the 1761 court of inquiry with a documented list of what had happened to the fleet on Lake Ontario from 1760 to the outbreak of the Revolutionary War, it was concluded that the court of inquiry had to relate to one of two possible ships. These two ships had been captured from the French by General Amhurst in 1760. Additional documents were used to determine that the vessel which had run aground and been "cast away" was the renamed French corvette l'IROQUOISE.

Letters from the ship's commander to the commanding officer of Fort Niagara, Fort William Augustus ( Chimney Isle) and Fort Ontario, placed the "cast away" location of the Anson/Iroquoise in the area of the Narrows, which lies in the New York State waters of the St. Lawrence River between Wellesley Island and the mainland.

Having found this information, Michael Hughes and Dennis McCarthy began to talk to other divers about shipwrecks that had been found in the Narrows. They discovered that in 1962 divers had removed French cannons from a wreck on Niagara Shoal. The location of Niagara Shoal fit the description given in the 1761 court of inquiry on the loss of the Anson. One of the cannons had been donated to Jefferson Community College in Watertown, NY and is currently on display at the campus.

In 1972, a scuba diver from Syracuse recovered a wood stocked anchor from Niagara Shoal. The anchor had a large ring, which is typical of older anchors that used hemp rope. More modern anchors had smaller rings to be used with iron anchor chains. From photos, that were sent to the Smithsonian, the anchor was identified as being from the 18th century. SRHF members viewed the anchor in 1994 at the New York State preservation center at Pebble Island.

Niagara Shoal

In the early 1980's Michael Hughes and Dennis McCarthy were taken to the site of the shipwreck by Skip Couch of Clayton. The vessel was laying in 65 ft to 80 ft of water. At the time, visibility was very poor and the shipwreck was very difficult to dive due to very strong currents at the site. A limited survey of the vessel showed it was in a deteriorated state. It was completely open with only the very lowest potion of the vessel remaining. Having been a diving site since 1960, no visible artifacts remained.

In 1993, interest in this vessel rekindled when 

 Peter Engelbert, Staff Archaeologist from the Ontario Ministry of Culture and Tourism, to visited the site. Dennis McCarthy and Michael Hughes returned to Niagara Shoal for the first time in over ten years. It was evident that the vessel had deteriorated greatly. It was completely covered in zebra mussels, adding significant weight to the extremely fragile structure. With the renewed interest in the shipwreck and concern for its deterioration, the St. Lawrence River Historical Foundation Inc. (SRHF) was formed as a non-profit corporation in July of 1994. SRHF's charter is to promote research and education regarding the maritime history of the St. Lawrence River. The IROQUOISE PROJECT of SRHF is designed to document through non-contact methods the wreck on Niagara Shoal and to preserve this information for future generations, regardless of what happens to the vessel itself.

Niagara Shoal Wreck Site

Iroquoise 1759 - 1761

The Niagara Shoal Wreck Site is at approximately 44.17.22 latitude by 76.00.33 longitude. Located in the Town of Clayton, Jefferson County, New York State, it is situated in the upper narrows of the American Channel of the St. Lawrence River. Niagara Shoal is marked by US Coast Guard buoy number 211. Niagara Shoal is a rock ledge that runs several hundred feet due north from Susan Island to the green buoy number 211. Not more than 0.2 miles from the site is Grass Point State Park, where buoy 211 can be seen from the docks and launch ramp area. The green buoy 211 is the outer channel marker for the St. Lawrence Seaway, which runs adjacent to the wreck site. With a shallow depth of about 5 ft (1.5 m), depending on river level, the shoal drops to about 180 ft (54 m) in depth in the center channel. Both sides of the shoal run from about 30 ft (9.1 m) deep near Susan Island to over a hundred feet deep near the peak of the shoal. The shoal runs diagonal to the current, which can be several knots at times. The Niagara Shoal Wreck rests on the down river side of the shoal in 65 ft (19.8 m) to 80 ft (24.4 m) of water, about 150 ft (46 m) SE toward the mainland from the buoy. 

Niagara Shoal Wreck Site Underwater

Resting in cracks and crevices on top of Niagara Shoal are several bricks and wood pieces. The wood is similar to that on the wreck in both the shape and style of some of the small fasteners. In all, about five to six pieces have been observed. None of the pieces are longer than 1 meter. Some of the wood appears to be charred, as if it had been in a fire. Descending down the channel from the peak of the shoal are a series of rock ledges and slopes of mud covered with snail shells. What appears to be a very straight wooden pole over 10 ft (3 m) in length and .5 ft (.15 m) in diameter is located just above the wreck site. On the slope above the deep end of the wreck is a triangular wooded crib in 65 ft (19.8 m) of water made out of hand-cut logs. The length of the logs is about 10 ft (3 m). The shallowest part of the wreck is at a depth of 65 ft (19.8 m) just below the previously mentioned wooded pole. At this shallowest point, the frames to the upriver side of the shoal are almost vertical, while the frames to the down channel side rest on their sides. The tip of the keelson starts at this point and runs over 66 ft (20 m) to the deepest part of the wreck in 81 ft (24.4 m) of water. The frames extend from both sides of the keelson in various stages of decay. Located near the deep end of the wreck is a large round timber that is about 10 ft (3 m) in length and 1.6 ft (.5 m) in diameter. Around the base of this timber is an iron band. Ten meters to the down channel side of the wreck is a sunken spar buoy and granite weight. One hundred meters on a line with the keelson and directly ahead of the wreck is another wreck in about 95 ft (30 m) of water. This wreck seems to be a turn of the century motor boat. It is covered in snail shells and overburdened. 

Brief History of the Site

For an unknown period of time, the remains of a vessel on Niagara Shoal were visible during the fall when the temperature of the St. Lawrence River dropped and the water clarity improved because of a reduction of algae. As late as 1919, newspaper articles (1) described the visible remains of a vessel of war in about 25 ft (7.6 m) to 30 ft (9.1 m) of water. It was assumed at the time to be a vessel of war due to the fact that numbers of cannon balls, shot, and weapons had been found on islands adjacent to the shoal. In the early 1960's, scuba divers found and recovered from the vessel three cannons and an anchor (2). Two of the cannons were of French origin and the third was English. The anchor had been damaged; one of its flukes broke off when it was caught under the side of the barge that was raising it. The anchor's very large ring was wrapped in tar-coated burlap. One of the French cannons was given to Jefferson Community College in Watertown and is currently on display in the commons of that facility. The other two cannons and the anchor are in the Binghamton, New York area. Scuba divers in the sixties reportedly found a large number of belt axes inside the hull of the vessel. Because of this, the diving community referred to the site as the Belt Ax Wreck. In 1973, a diver found a second anchor on the up channel side of the shoal on a gravel bed. This anchor also had a large ring and part of its hemp hawser was still attached. The anchor was recovered and, after the diver preserved it in polyethylene glycol, loaned it to the Sackets Harbor Museum, which in turn eventually shipped it to the Pebbles Island storage facility. Fellow diver Michael Hughes and I first saw the site in the late 1970's. At that time, the visibility on the site was less than 5 feet and lights were required. Zebra mussels had cleared the visibility by 1993. 

Field Investigations 

Dive Season 1 1994

The primary goal of the 1994 season was to survey the Niagara Shoal site and determine enough information to file for a detailed survey permit. Starting in September, a general survey was made of Niagara Shoal and the wreck site. A site sketch was made that was used in preliminary measurements. The entire site was video taped and the peripheral to the site was searched. Besides the wreck, other large objects located near the wreck were discovered and recorded. Some of these items were a triangular crib of hand hued logs, a sunken spar buoy with a large granite base, a metal spar buoy and a wreck of an turn of the century wooden hull boat.

Dive Season 2 1995

During the time period from June 1995 to October 1995 , 18 volunteer divers made over 100 dives on the Niagara Shoal Wreck. The primary goal of the 1995 season was to map and photograph all exposed structural remains of the vessel. The Direct Survey Method (DSM) of measurement was selected for mapping the exposed structure of the wreck. Nick Rule developed this technique for use on the MARY ROSE in England. For this method, data points consisting of a number 6 galvanized nail with a plastic label tag are placed on the vessel. Each data point requires two criteria: they need line of sight to a minimum of 3 others (but preferably 6 or more) and they need line of sight to areas that are to be mapped. The number of data points needed is determined by the number of points required to provide direct measurements of a minimum of three (but preferably four) to each item being mapped. Once the datum points were placed, all the direct distances between all the primary datum points were measured. A site measuring map was developed from basic measurements of the wreck in the fall of 1994. This site measurement map was then used in selecting data point locations and in developing measurement plans for dives. Eleven data points were placed on the wreck. Peter Engelbert selected each point using the previously stated requirements. Data points were tagged with plastic cards numbering from 1 to 11. A loop of plastic was placed over key objects to be located by the DSM measurements. Preliminary site DSM data preparation and evaluation was done by Alan MacEwen. With the primary Datum points set as the reference points for further work, they were then measured between each other with the distances being recorded. This data was computer processed to generate the XYZ coordinates. Confidence in the Z-coordinate of each primary datum point was increased by taking relative depth measurements with an underwater air level. Once the work on the primary datum points were completed, the dive activity shifted to recording distances from the datum points to key structural objects. A team of three divers were used for measuring. Before entering the water, the dive team would determine the measurements to be made that dive from a site map located on the dive boat. A table of the datum points and objects to measure were printed on a waterproof paper attached to a clipboard. The divers would then enter the water and when all divers were ready, descend down the slope to the wreck site. Once on the wreck site, the first diver would attached the measuring tape to the nail marking a datum point. The second diver would extend the tape to the object to be measured. The third diver would make sure that the tape was tight and not obstructed and then record the measurement on the waterproof paper. At completion of the measurements or when the first diver's scuba tank got down to 1000 pounds of air, the team would return to the surface. Given the depth of the wreck, diving on air only and the diving conditions, the average dive time for a team was about 20 minutes to complete about 10 measurements. Longer dives were achieved with the use of Nitrox Scuba Tanks but this was only used during the placement of the Datum points. In order to avoid nitrogen build-up problems (bends) caused by repetitive dives, a two dives a day limit was enforced for each diver.

The Internet was used extensively by members of the survey team to exchange data and coordinate dives. Nick Rule, who developed a computer program for processing DSM data, volunteered to process the information from this project free of charge. Data was formatted for his computer program and sent via the Internet to England for processing that yielded X,Y,Z coordinates and measures of confidence in these coordinates. Some of the initial measurements had to be remeasured when they were identified by the DSM program as being of low confidence.

An initial photo-mosaic of portions or the wreck was made by swimming over portions of the wreck and taking sequential pictures. Once developed, these pictures were fitted together by hand to be used with the site drawing for identification of wreck features.

The Niagara Shoal site is located in one of the major sport scuba diving areas of the St. Lawrence River as well as on a favorite fishing spot. Even though we experienced no problems from other divers or fishermen while we were on site, we did find one problem. The last frame on the wreck that contained datum points F and G was discovered moved from the wreck. It was found in about 35 feet of water above the wreck on the slope of the shoal. It appeared to be in good condition and since it was moved after most of the DSM measurements were completed it could be replaced in the wreck close to its original position if needed. It most likely was caught by a boat's anchor and dragged away from the wreck in order for the boat to free itself.

Dive Season 3 1996

The goal of the 1996 season was to obtain more DSM measurements of the wreck site as well as to check certain measurements that were highlighted by the DSM software as being of low confidence and to develop a detailed photo-mosaic. Measurements of several major structural features were made in detail. An expanded search/survey of the area surrounding the wreck was carried out during several dives. In 1996, smaller dive groups were used in order to get more precise information. Each dive team consisted of only 2 to 3 divers. The photo-mosaic was achieved by photographing three sets of overlapping photographs of the wreck. Anchors with 10 foot lines attached to fillable containers were placed at each end of the wreck at an offset of about 10 feet from the center line of the keelson. Each container was filled with air and a line with premarked intervals of 5 feet was tied between the air filled contains. The lift provided by the buoys was sufficient to hold the line between them relatively straight with less than a one foot curve over about 60 feet run of the line. A diver with a level on his camera then swam the line taking pictures at every marked interval pointing the camera down while keeping it level in the XY plane. On completion of a 'photographic run', two divers would move the anchors from side to center then to the next side. Thus allowing a complete set of pictures to define the entire wreck. The frames containing datum points F and G that were moved on the site (see last year report on site disturbance) were placed back near the site but not on the site at this time. The frames were also measured in detail. No additional noticeable disturbance was detected at the site during the 1996 season. It was fully videotaped at the end of the year as well as partially taped several times during the summer.

Expanded search: Several dives were made to the 120-foot depth below the Wreck site. The purpose of this was to see if any debris from the wreck was present. The only major find was a large iron container about 3 feet high and two feet round. This was measured and photographed as well it's general location was marked.

In total over, 31 dives were made on the site by 8 divers. This year smaller teams were used so as to be able to get more precise information. Each dive consisted of only 2 to 3 divers.

Dive Season 4 1997

Dive season four was spent reconfirming some of the measurements from the previous season and doing more general site survey. Dives were made to the 130 foot depth both below the wreck and up channel from the site.

On one dive an empty divers "goody" bag was found on the site as well as what appeared to be a disturbed bottom outside the wreck structure. No other noticeable disturbances were seen. 

Underwater Video

Several hours of underwater video were recorded over the 4 year diver period. In additional to the remains of the hull all other object in a 50 meter surrounding area we recorded. This includes the second wreck, spar buoy, some cribbing and other objects.

Underwater Still photography

General photography was used to record major structure of the remains of the vessel on Niagara Shoal. Print, slide and video were used to ensure complete documentation of the site. As well as general photography, both photographic and video mapping was done in the plane of the keelson to provide image data that can be used in development of a photo-mosaic. Underwater photography was provided by Gerry and Joyce Wall of U/W Concepts, Ottawa Ontario, Canada.

Quick Photomosaics

Taking advantage of the visibility on the dive site several "quick Photomosaics were made of the site. A diver with a camera would swim over the wreck and take continuos photos . Once the Photos were developed they would be placed over each other to produce an image of the site. 

Computer processed Photomosaic

A photo CD has been created with over 60 key photos of the wreck. The visibility of over 40 ft (12 m) on site allowed available light photographs to be made of the entire wreck from a height of about 10 ft (3 m) above the bottom. An experimental photo mosaic was done of the keelson section of the wreck using photo-mosaic means to generate a continuos photo of the center section of the wreck. The Photo CD will allow computer processing to provide for a complete seamless photo-mosaic. 




Photo Mosaic digital processing provided by Kendrick McMahan

Capt. Alain DEMERLIAC, 18th Century French Naval Architecture

Archeologist, Peter Engelbert

DSM measurements process by Nick Rule

A. Britton Smith of Kingston Ontario, Historical research.

Dive support was provided by SOS Prescott and Sea N Sky Scuba of Prescott.

Still photographs by Gerry & Joyce Wall of U/W Concepts of Nepean, Ontario

Underwater Video housings by Ocean Image, Inc. of Ithaca, NY and Cape Coral, Florida

Underwater video by Michael Hughes

Photomosaic digital processing provided by Kendrick McMahan

Preliminary site DSM analysis by Alan MacEwen, Glouchester, Ontario

Legal expertise by Todd Smith, Syracuse, New York

Donald 'Moe' Hunt Watertown, New York

Wilber Wahl French Creek Marina Clayton, New York

Mike Williams, Site photo's

David G. White, NY Sea Grant

Survey team

The following divers participated in the project .

(No particular order)

Skip Couch Clayton, New York

Don Martin Lyn, Ontario

Greg Boyer Syracuse, New York

Bob Seiselmyer Syracuse, New York

Don Phillips Waterloo, New York

Michael Hughes Little York, N.Y.

Dennis McCarthy II Syracuse, New York

Dennis McCarthy Syracuse, New York

Ian Boyden Boston, Mass

Peter Engelbert Ottawa, Ontario

Gerald Wall Nepean, Ontario

Joyce Wall Nepean, Ontario

Alan MacEwen Gloucester, Ontario

Twyla MacEwen Gloucester, Ontario

Adam W. Rushton Gloucester, Ontario

Lou Bumbala Kemptville, Ontario

Karl Tylman Brockville, Ontario

Dave Ostifichuck Smith Falls, Ontario

Gerald McGregor Nepean, Ontario

Jeff Manger Syracuse, New York

Mike Johnson Ithaca, New York

Mike Williams Kitchner, Ontario

Ron Brunet Kemptville, Ontario

Shannon Kelly Ogdensburg, N. Y.

Ross MacKan Kemptville, Ontario

Dave Cooper Oxford, Ontario

Scellig Stone Manotick, Ontario

Daithi Stone Manotick, Ontario

Alastair Champion Manotick, Ontario

Fraser Champion Manotick, Ontario

Ralph Hoskins Scarborough, Ontario

Scott Humphrey Scarborough, Ontario

Phil Rafferty Lindsay, Ontario

Steve Knobel Kemptville, Ontario

Saint Lawrence River Historical Foundation (c) 1994 - 2004