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Salvage for Science
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ROV:
Remotely Operated Vehivle (ROV) rigged for action with hook, lines and sonar.
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From December 1999 to April 2000, the Woods Hole Field Center (WHFC) deployed a regional
array of six tripods on the seabed and five surface moorings to study sediment transport
and circulation along and across the New York Bight and Hudson Shelf Valley. There is
always risk associated with deploying instrumentation and the more gear one puts out,
the greater the risk. With luck and skill, we recovered all the gear on the scheduled
recovery cruise, except the most strategic tripod at Site B, where both the valley-axis
and cross-shelf lines of instruments met. The tripod's recovery float came to the surface
towing the lifting line, but due to chafing, the line parted when we pulled the tripod
off the bottom. We dragged the area with sturdy 150-lb grappling hooks, hooking the
tripod once or twice and tipping it over, but we were unable to bring it to the surface.
Deteriorating weather and lack of ship time finally sent us home, leaving over $75,000
of instrumentation with its data on the bottom.
We regrouped and enlisted the help of a Woods Hole Oceanographic Institution (WHOI)
remotely operated vehicle (ROV). Jonathan Borden (WHFC) and Andy Girard (WHOI) spent
a week getting the unit in shape, devising rescue hooks to attach to the ROV and practicing
off the WHOI dock on spare tripods we had on shore. In late June, we secured time on the
R/V Connecticut, and Jon, Courtney Harris, Dave Foster, Marinna Martini, Ben
Gutierrez and Jane Denny (WHFC) joined Andy to head back to New York for a second try.
As we were loading, Dan Codiga of the University of Connecticut asked us if we could
attempt to rescue a lost bottom package off Montauk, NY, if we had time on our way home.
Crowded Deck:
Tripod on a crowded deck prior to deployment.
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We arrived at the NY Bight tripod site at 0400, completed verification of the tripod's
location in a fast two hours, deployed the ROV and had the tripod on deck by 0800 in
spite of very poor visibility for the ROV on the bottom. Jon and Andy's hook-up rig
worked like a charm (see ROV photo). We had so much time left, we returned home by way
of Montauk Point and had a "go" at Dan's gear, recovering that too! At 2300 on the same
day that we had arrived at the NY Bight site, we were headed back to the dock with two
prizes on board. Not only did we retrieve the tripod but all the instruments were also
in good condition. Courtney, one of the principal investigators, reports that the data
look excellent with intriguing up-valley near-bottom currents.
Many thanks to Andy for his piloting, Jon for handling cruise logistics and for his
help and expertise with ROVs (from his old Alvin days), Jane and Ben for navigation
via GIS, and Courtney and Dave for their help on deck. Dan was very grateful to everyone
for willingness to put in an extra long day to try for his instruments. May all science
expeditions go so well!
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August 2000
in this issue:
cover story:
Biscayne Nat'l Park Corals
Santa Monica Bay
Salvage for Science
Joint USGS—Monterey Aquarium Cruise
Teachers Tour WHFC
Students Tour WHFC
West Falmouth Harbor Water Sampling
World's Largest GIS Conference
Modeling Workshop
SC/GA Coastal Erosion Project
NOAA Data Integration
Talk at WHFC
New Babies in Western Region
New Coastal & Marine Geology Circular
August Publications List
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previous story
U. S. Department of the Interior | U.S. Geological Survey