On Board With NOAA Hydrographer Ben Evans

Find out what it's like to run the National Oceanic and Atmospheric Administration's new high-tech coastal mapping ship.

September 10, 2012

What’s a hydrographic field party? It sounds like it could be a wild time.
Well, that all depends on how you define wild. If surveying the pristine unmapped wilds of Alaska or working under pressure to reopen a major port to maritime commerce after a hurricane sounds like fun, work on a hydrographic field party might be for you. Hydrographic field parties are part of the 200-year tradition of the U.S. Coast Survey. President Thomas Jefferson signed legislation authorizing a survey of the United States’ coast, to produce charts for the nation’s fledgling shipping industry.

How long does the party last? How many days do you stay out on the water at a time?
The length of each mission depends on the type of vessel and the project. When Hassler is surveying an offshore area, like we are doing this summer off the coast of New York, we stay out for 10 days to two weeks at a time and run hydrographic survey operations for 24 hours a day.

Do you call yourselves NOAAmads?
That’s a great play on words! The navigation response teams are the most “NOAAmadic,” since the Office of Coast Survey moves them around from state to state, responding to survey requests from ports and pilots. But those of us on “NOAA’s Arks” (the ships) are really not like nomads who don’t have permanent homes.


What’s a typical day like on the water mapping?
There really isn’t a typical day in hydrography. Some days are more thoughtful than exciting, as we systematically map an assigned area of the seabed that turns out to be free of the surprises — we sometimes call this deliberate back-and-forth survey work “mowing the lawn.” Other days are quite hectic, though — whether because we are dealing with the inevitable hiccups in our survey gear and ship systems, working among heavy maritime traffic in a busy port or challenged to find a way to stay productive in unfavorable weather conditions.

What types of technology do you use — how many different types of sonar to collect the data?
Hassler is equipped with four different sonar systems: shallow-water multibeam echo sounders, a midwater multibeam echo sounder, vertical-beam echo sounders (one in each hull) and side-scan sonar. We also rely on high-accuracy position and attitude sensors that combine GPS and accelerometers to measure the ship’s position, heave, pitch, roll and heading. Also critical are our sound speed profilers, which allow us to measure the speed of sound through the water column and correct the sonars’ acoustic signals refraction and travel time.

What’s the most unexpected thing you discovered during a survey?
That’s a tough question — one thing that I’ve learned in 12 years as a NOAA hydrographer is that there are a lot of odd features on the seafloor, both natural and man-made, so very little surprises me anymore. One of the strangest things I have encountered, though, was a complete steam-driven engineering plant sitting on the bottom of Long Island Sound. We found boilers, a steam engine, propeller shaft and large (approximately 8-foot diameter) propeller — but no ship! Presumably it was all that was left of a wooden-hull ship that sank or was scuttled and then gradually rotted away.


Is the job ever dangerous?
Beyond the normal hazards of life at sea, the danger in this job comes when we are needed to reopen ports after hurricanes or other emergencies. When a hurricane is barreling toward shore, NOAA is deploying our hydrographic assets so we can hit the water after the hurricane leaves. We need to survey the ports or sea lanes, looking for underwater dangers to navigation, like debris or shoaling, before the Coast Guard will allow shipping to resume.

How will your new vessel, the Hassler, change your job?
Hassler is an unusual piece of engineering. The ship is a small-waterplane-area twin hull (SWATH) design, which is a specialized catamaran with most of the buoyancy well below the waterline. This makes the ship more stable and less influenced by the action of wind and waves than a comparably sized monohull, improving the quality of our hydrographic data and allowing us to continue working in rough weather.

When will the work you’re doing now show up in our chart plotters?
Five years ago, it could take four years to update a chart using new survey data. Today, using new technologies and processes, NOAA can process the survey and update the charts in less than a year; we can complete high-priority surveys in 90 days.


How does one become a hydrographer?
Love the ocean. Mess about in boats. Get excited by science and math.


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