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Monitoring the Wreck of the Florida with Side Scan Sonar, and a new Florida Webpage

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The twisted steel wreckage of the sunken steam dredge Florida can be seen in this sonar image. The Florida was lost in 1918 off Crescent Beach, south of St. Augustine.

An important aspect of our First Coast Maritime Archaeology Project, and one of the basic tenets of our mission here at LAMP, is the regular monitoring of archaeological sites throughout our region. By visiting known sites regularly and keeping an eye on them, we will be the first to know if they are being negatively affected by storms, beach replenishment dredging, looting, or other man-made or natural actions. Until recently the only way to monitor shipwreck sites in our area was to conduct a dive to get down to them in person. With the support of our First Coast Maritime Archaeology Project historic preservation grant from the state of Florida's Division of Historical Resources, we have changed that. Now we can take our new side scan sonar system and scan known sites with relative ease, in effect creating a database of snapshots giving us an idea of how each wreck looks over time.

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The dredge Florida was a sternwheel steamboat designed and operated as a dredge and snag vessel. Built in 1904, it was used by the U.S. Army Corps of Engineers to operate in the East Florida Canal, today known as the Intracoastal Waterway. She was renowned at the time for being the most technologically advanced vessel of its type, and her designer John W. Sackett incorporated several of his own patents in the vessel's design. From the time of her launching until her loss fourteen years later, the Florida worked constantly deepening the channel of the East Florida Canal and clearing it of sunken logs and wrecks. In 1918, the Florida was forced to make the offshore return route to Jacksonville because drought had severely lowered the water level in the Canal. On this fatal voyage the ship was struck by a storm off Crescent Beach, quickly foundering moments after the order to abandon ship was given. Among the three lives lost were an African-American seaman and Sackett himself.

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The wreck was discovered by LAMP archaeologists in June 2003, using a similar side scan sonar system to that which we now own. Divers at the time confirmed the identity of the wreck and its basic extent and condition. Relatively intact, the wreck is oriented roughly a north-south axis, and rises to as high as 15' from the seafloor in about 51' of water.

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LAMP crew Sam Turner, Renee Post, and Brendan Burke showing off the new side scan sonar towfish.

In July 2008, LAMP crew members visited the site and produced sonar imagery (two of which are pictured above) of this wreck for the first time in five years. Our new device, a Klein 3900, is considered the top-of-the-line acoustic survey technology. It works by towing a sensor unit, or fish (seen above) behind the boat. The towfish emits high frequency soundwaves projecting out and downwards on either side, which bounce off the seafloor like radar and are in turn received by the fish.

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Sam checks out the sonar laptop while Brendan drives the boat.

These signals are interpreted on a laptop screen to form a bird's eye view of the seafloor. This system is an important tool for the search for shipwrecks, and for the monitoring of wrecks whose locations are already known.

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Brendan takes a turn as the sonar operator at the laptop screen.

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One of the benefits of working offshore is the chance to view marine life close up. At first we thought this was a pair of dolphins (humans are not the only ones to use marine sonar!) but we realized this was a sight more rare--two large rays apparently mating.

Since our recent acquisition of the sonar system, we have used it to monitor a number of archaeological sites, including the Florida, the Centerboard Schooner Wreck, the Steamship/Ballast Pile Wrecks, the Industry, and the Tolomato Bar Anchorage site, an 18th-19th century wharf site in the Tolomato River. It has proven a great tool for this kind of monitoring, and it will allow us to create a useful record of site changes over time. Stay tuned for more images of these wrecks . . . !

Announcing a New Webpage!
And by the way, for those who may not have seen the LAMP webpage in a while, we have put up some new material in recent months. This new work includes a page dedicated to the wreck of the Florida, which includes a more complete historical overview, lots of construction information, biographical information on Sackett, a photo gallery with lots of above and underwater pictures, a video library with a dozen underwater videos taken on the wreck, and much more! Check it out by clicking here!

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