A Remote-sensing Survey of Key West Harbor and Approaches,

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A Remote-sensing Survey of Key West Harbor and Approaches, 2003-2004 Magnetometers Ready to be Deployed, Key West Harbor, December, 2003

1 A Remote-sensing Survey of Key West Harbor and Approaches, Magnetometers Ready to be Deployed, Key West Harbor, December, 2003 Prepared by: Corey Malcom Mel Fisher Maritime Heritage Society 200 Greene St. Key West, Florida In Accordance with FKNMS Permit #

2 Acknowledgements: Phase 1 of the Key West Harbor archaeological survey has been completed only through the efforts of many. Logan Mitchell, John Wray, Craig Jones, Bruce Darby and George Robb, Jr. of the RPM Nautical Foundation conducted the remote sensing-surveys. Jeff Royal and George Robb, Jr. of RPM processed the magnetic data. Howard Phoenix, Craig Jones and John Wray of RPM, and Sara Tinsley of the Mel Fisher Maritime Heritage Society conducted the reconnaissance diving to identify targets. All underwater photographs are by Howard Phoenix.

3 Phase 1: Archaeological Investigations of the Key West Harbor, Project Overview: Maintenance dredging of the Key West Harbor is scheduled to begin in early To identify, and alleviate any potential impact on archaeological resources, a preliminary archaeological survey of the areas to be affected was conducted. The initial phase of this assessment was a magnetic remote-sensing survey. A number of man-made objects have been identified through this effort, including some of significance. The results of this survey will be used to guide any further archaeological research within the Harbor. Purpose: Key West Harbor was used intermittently in historic times from 1513, when the first European explorers passed through the area, until the early 1800 s. Since 1822, with the island s permanent settlement, it has served continuously as the main point of entry and anchorage for private, commercial and military vessels. As crews and passengers engaged in the course of their daily routines, objects were lost or disposed of overboard. Shore-side activities resulted in similar losses. Over time, many man-made objects have found their way onto the sea floor, and remain there, resulting in an area of concentrated debris. Throughout the recent past, many artifacts from all periods of the islands history, have been collected from the harbor by recreational scuba divers. As large ships enter and exit, they churn the bottom sediments, and objects are constantly being both covered and uncovered. Before beginning this survey, it was expected that many significant artifacts remained, both buried and exposed, within the proposed dredge areas. The harbor was dredged to a depth of 34 feet in the 1960 s, and the 2004 dredging project is planned as maintenance dredging, designed to return it to its 1960 s level. Significantly, the current dredge plans include a provision to go to 37 feet an extra degree of excavation to ensure the desired controlling depth is achieved, and which may impact in situ archaeological preservation. Beginning November of 2003, at the request of the State of Florida Bureau of Archaeological Research and the Florida Keys National Marine Sanctuary, the Mel Fisher Maritime Heritage Society (MFMHS) and The RPM Nautical Foundation (RPM) began an archaeological survey of the Key West Harbor. This survey was intended to mitigate any impact to submerged archaeological resources that might result from the US Navy dredging project of the area, set to commence in This work is planned in two phases, with the first being the remote sensing of the proposed area of impact. The second will be the recovery of archaeological resources, both as dictated by the results of Phase 1, and also through a random sampling strategy. With the completion of the magnetic survey of the impact areas, and identification of anomalies, selected cultural resources have been deemed significant, and should be removed before any damage or destruction occurs from the dredging.

A view of Lakota s back deck with magnetometer cables and reels during the Key West Harbor survey December 2003 Survey Methods: The 48-foot, aluminum-hulled R/V Lakota was used to tow an array of

4 A view of Lakota s back deck with magnetometer cables and reels during the Key West Harbor survey December 2003 Survey Methods: The 48-foot, aluminum-hulled R/V Lakota was used to tow an array of three Geometrics model 881 cesium magnetometers. Each magnetometer recorded the magnetic field found within its range. This data was then be interpreted as a gradiometer, utilizing the differences in readings between magnetometers. Each of these towed devices was spaced 5 meters apart. The magnetometers sampled the magnetic field at a rate of 0.3 seconds, while traveling at a speed over ground of between 3 and 6 knots. The survey vessel traveled in lanes spaced at 15 meters (approximately 1/100 th of a nautical mile), oriented with the direction of the proposed dredge channel, ensuring that one magnetic sensor passed over every 5 meters of the survey area. Consistent and accurate lanes were ensured through the use of Trimble s Hydropro Navigator software, and Lakota s combination of bow-thruster forward, and twin propellers aft. As the proposed survey area varies in depth from 40 feet to 30 feet, the towed gear was adjusted accordingly. The collected magnetic data was recorded via Geometrics MagLog Lite software, which allows the information to be merged with that from the Global Positioning System. Data was collected to three sets of CD s on a daily basis, as well as stored in the computers hard drives. The combined magnetic and geographic data provided information relating to the distribution of shipwrecks. The magnetic data was interpreted via Surfer 8.0 software, which produced charts showing magnetic intensity relative to the geographic position, via differential GPS, across the surveyed areas. Additionally, a 600mHz Marine Sonics sidescan sonar fish was towed across selected areas. The sonar was set to image either 25 or 50 meters to each side of the towed fish, depending on water depth. The sidescan sonar data was collected and interpreted through Sea Scan PC software, providing underwater, visual images of the surveyed tracks.

5 From this evaluation, divers assessed a total of twenty-six magnetic targets for their significance. These were selected by their magnetic intensity, and in some cases, their relationship to other known anomalies. Using GPS data, the boat anchored near each anomaly, and divers with metal detectors worked to pinpointed the hits. Their observations were recorded, and in many cases photographs were taken. In accordance with FKNMS regulations, there was no excavation during this phase of investigation. The survey computer s on-screen display of the magnetic signal as it was being recorded in Key West Harbor.

6 Boundary coordinates of the three areas - Cut A, Cut B, and the Key West Harbor covered by the remote-sensing survey.

7 The Survey Area: There are three areas of the Main Ship Channel and Harbor that are to be dredged. They run in approximately a north-south line from just west of the island of Key West, to the reef approximately 7 miles south. The areas to be dredged are bounded as follows: Harbor Entrance: N24º W81º N24º W81º End Mid Channel Range: N24º W81º N24º W81º CUT A Range: N24º W81º N24º W81º R12 (dog leg): N24º W81º CUT B Range: N24º W81º N24º W81º Harbor Perimeter: N24º W81º N24º W81º N24º W81º N24º W81º N24º W81º N24º W81º

8 Results: Based on the magnetic data, divers investigated selected anomalies, recording the details of their findings. The majority of anomalies were recorded in Cuts A and B. Key West harbor itself showed much less activity. The divers searches were conducted with the aid metal detectors. The following observations were made: Cut A Anomalies Investigated Anomaly Location Diver Comments 01 W Buried Object N W Multiple small buried readings N W Many medium buried readings N W inch diameter steel cable, same as #5 N W inch diameter cable, over 300 feet N W inch diameter cable N W Debris field, incl. 4x8-foot iron frame and chain N W Buried 4-5 foot diameter reading N W Small readings, unidentified N W Iron framework, plate, banding N W x14 foot buried hit N W x2 foot metal bands N

9 Cut A Magnetic Chart with Investigated Anomalies

10 Cut B Anomalies Investigated Anomaly Location Diver Comments 01 W Soft silt, small hits, cans, iron rings N W Scattered modern wreckage, plates, shrimp-net, tire N W Piece of metal 20x1 feet, C-shaped N W Buried metal object, Iron Tank N W Danforth-style anchor, lbs. N W foot Anchor, Metal chair frames, line N W Oil-pan from engine N W foot iron bar with 20-inch sq. ends N W Iron bracket and 24-inch steel bar N W x 14-inch anchor palm N W I-beam, pulley, pipe, bundle of line N W x 6-foot iron plate, I-beam, netting N W Very large anchor in two pieces with 100ft of chain N Misc. metal debris, glass bottles, ceramic dishes 14 W Crank and pole, Iron plate 30 x 15 inches N

11 Cut B Magnetic Chart with investigated anomalies.

12 Cut B Anomaly 2 I-beam fragment Cut B Anomaly 2 Iron Pipe or Outrigger section Cut B Anomaly 2 Netting Cut B Anomaly 2 Tire Cut B Anomaly 2 Scattered Metal Debris Cut B Anomaly 2 Scattered Metal Debris Anomaly B-2 proved to be scattered debris, most likely from a modern commercial fishing vessel. Though none of the hull was found, significant portions such as rigging and netting were, suggesting that this may have been a site where the trawling gear snagged, tearing portions of this equipment away from the vessel.

13 Cut B Anomaly 3 Flattened Pipe, End View Cut B Anomaly 3 Long View Anomaly B-3 is a roughly 20-foot long iron pipe that has been flattened. It may be part of a commercial fishing vessel s outrigger. Cut B Anomaly 4 Cylindrical Iron Tank Cut B Anomaly 4 Partially buried iron object Anomaly B-4 is an iron tank with mounted valves, and a partially buried object. The blackish appearance of the concretion, with loose rock and shell adhesions suggests the latter is made of modern iron. Cut B Anomaly 6 Anchor Cut B anomaly 6 Chair and Line Anomaly B-6 is an iron-stocked anchor, approximately 6 feet long. Associated is a tangle of line surrounding at least one metal chair frame. The anchor is of an older design.

14 Cut B Anomaly 7 Oil Pan From Engine Cut B Anomaly 8 Five-foot iron bar with 20-inch square ends Cut B Anomaly 8 View 2 Anomaly B-8 is a large, 5-foot long iron bar with 20-inch square plates fixed to both ends. It is roughly the size of an axle and pair of wheels from a train, but its original function is unknown.

15 Cut B Anomaly 10 Cut B anomaly 10 Anchor Palm Anchor Palm Anomaly B-10 is a heart-shaped, iron anchor palm. It has been detached from the anchor. Cut B Anomaly 11 Pulley Set Cut B anomaly 11 Tangle of Line A combination of pulleys, I-beam, iron pipe, and a tangle of line at Anomaly B-11, suggests this is snagged trawling gear from a commercial fishing vessel. Cut B Anomaly 13 Detached Anchor fluke View 1 Cut B Anomaly 13 Detached Anchor fluke view 2

Cut B Anomaly 13 Anchor shank, View 1 Cut B Anomaly 13 Anchor

Anomaly 13 Iron Box Anomaly B-13 is actually a large area with

over 100 feet of chain attached to the shank, and one detached

A variety of other iron and aluminum objects are nearby.

dishes, many of which appear to be 100+ years old.

16 Cut B Anomaly 13 Anchor shank, View 1 Cut B Anomaly 13 Anchor shank, View 2 Cut B Anomaly 13 Anchor Chain and Shrimp Net Cut B Anomaly 13 Misc. Iron Debris Cut B Anomaly 13 Dark green glass wine bottle Cut B Anomaly 13 Iron Box Anomaly B-13 is actually a large area with the most prominent feature being a large stockless anchor with over 100 feet of chain attached to the shank, and one detached fluke. It appears the fluke was designed to be removable. A variety of other iron and aluminum objects are nearby. Also associated are a number of glass bottles and ceramic dishes, many of which appear to be 100+ years old. The area looks to be both a dumpsite, and a collection area for items washed out of context by both natural and propeller induced forces.

17 Key West Harbor Magnetic Chart

18 Conclusions: The majority of the investigated anomalies were composed of modern debris. Two, Anomaly B-6, and Anomaly B-13 are the locations of iron anchors that are of interest. Anomaly B-6 is an iron-stocked anchor that could be as old as 150 years, judging it as it is found. At Anomaly B-13 there is a large stockless anchor in two pieces with a large amount of chain. It is of undetermined age or origin. The dive-training program at the Florida Keys Community College has expressed an interest in removing these anchors to their underwater research area, adjacent to the Stock Island campus. This same facility houses the wooden hull remains of the 1622 Spanish galleon Nuestra Señora de Atocha, and would be a good place to preserve the anchors, while also allowing them to be available as an educational resource. Throughout both Cuts A and B there were buried magnetic anomalies, but the potential for their significance is diminished by the fact that these areas were previously dredged in the mid-1960 s. If time allows, there might be some interest in excavating a sampling of these. Otherwise, the potential is still strong for non-magnetic items to be found within the proposed dredge area, especially within Key West harbor itself. At Anomaly B-13, there are a number of bottles and ceramic items that appear to be over 100 years old. A sample of these should be collected. A system of sampling areas of the Harbor itself should be employed to gain some understanding of the similar types of materials that can be found there. At selected points within the boundaries of the dredging operation, divers should collect all cultural materials that can be found within a given radius of the point. To ensure proper post-recovery documentation, the Mel Fisher Maritime Heritage Society has agreed to provide conservation and curatorial services for any recovered objects. With such a strategy, enough material can be observed and collected to give a good sense of the cultural materials found at the bottom of one of the oldest harbors in the state of Florida, as they existed at the beginning of the 21 st century.

REPORT OF INITIAL SURVEY OF AN UNKNOWN BARGE OFF OF CEDAR POINT, SANDUSKY, OHIO. July 26-27, Submitted to Cleveland Underwater Explorers, Inc.

REPORT OF INITIAL SURVEY OF AN UNKNOWN BARGE OFF OF CEDAR POINT, SANDUSKY, OHIO July 26-27, 2008 Submitted to Cleveland Underwater Explorers, Inc. By Jack Papes SUBJECT Report of Initial survey of an unknown