Ride with the tide
NOAA's sensor-laden, Web-accessible system makes ports into safer havens
- By Patrick Marshall
- Feb 14, 2008
Any port in a storm? In a pinch, sure. But, particularly in a
storm, not all ports are equally safe. Any sailor worth his salt
would advise you to favor one supported by the Physical
Oceanographic Real-Time System program.
Developed by the National Oceanic and Atmospheric
Administration, PORTS provides real-time oceanographic and
meteorological data that can make the difference between smooth
sailing and running aground or crashing into a bridge. With the
addition in December of the Port of Mobile, Ala., PORTS is
operating at 14 locations nationwide with more additions
Specifically, PORTS measures, integrates and disseminates
observations of water levels, currents, salinity, wind and bridge
clearance from 50 sensors. The data is updated every six minutes
and can be received by mariners ' or anyone else ' via
cell phone or Web browser.
Based on the PORTS information, a ship's pilot can decide
to delay entering or leaving a port. Alternatively, a ship's
master could decide that the ship could take on extra cargo if
there is, say, an unusually high tide. The information not only
affects safety but also can significantly impact the bottom line
' for cargo carriers, port authorities, first responders and
Born of disaster
Darren Wright, NOAA's program manager for PORTS, said the
program came about as a result of the Tampa Bay, Fla., Sunshine
Skyway Bridge disaster in 1980. The southbound span of the bridge
was destroyed when a freighter collided with a support column
during a storm, sending vehicles into the water and killing 35
'After that happened, it was determined the current pushed
the tanker into the bridge,' Wright said. 'If we had
some real-time current information that may well have helped avoid
the problem. Since we had some of the equipment that was necessary
for the information they were looking for, we designed a system
in-house to provide real-time information that the mariners could
use to avoid groundings and to promote efficient and safe
The first PORTS system was installed at Tampa in 1991.
PORTS was developed from the start to be a partnership between
NOAA and the local port authority. NOAA delivers the expertise,
data management and ongoing support, and the local port authority
provides funding for the equipment and maintenance of the
In its first incarnation, PORTS data was accessed via direct
dial-up to the PORTS database.
Shortly thereafter, a voice system was added that allowed users
to call in for information.
Internet access was added in 1996.
Data is transmitted from on-site sensor platforms to NOAA
headquarters in Silver Spring, Md., primarily via IP modems. The
system also has access to NOAA's Geostationary Operations
Environmental Satellite data, although it's not often
'There's too much data to transmit over the
satellite in the windows that we're allowed to use, so the IP
modem is the primary method,' Wright said. PORTS has access
to the satellite only in one-minute blocks, and because the
transmission rate is only 1,200 bits/sec, the satellite cannot
deliver the data flow required for PORTS' near-real-time
Wright added that where the signal is not sufficient for IP
modem use, radio transmitters get the data to a working IP
Approximately 769M of decoded data is processed per day to
support the 14 participating ports.
PORTS has already earned high marks from users ' and
'We have been exceptionally pleased with it,' said
James Lyons, director and chief executive officer at the Port of
Mobile. 'It's very, very valuable information. We run a
lot of deep-draft vessels in and out of here. It has been giving us
invaluable information on the timing of arriving and sailing
vessels from a safety standpoint. Having that accurate information
also enables ships to put on just a little bit more cargo if we do
have a good positive tide.'
Number crunchers agree. In two studies on the economic benefits
of PORTS, analysts for the port authorities found that the system
saves as much as $7 million per year for Tampa and as much as $16
million per year for the Houston-Galveston port. The savings
include money not spent responding to such incidents as groundings,
collisions and hazardous spills, in addition to shortened wait
times for ships and the ability to load more cargo.
One report found just one additional foot of available draft
allows crews to load enough additional cargo to generate between
$36,000 and $288,000 in increased profit per trip.
Although the Port of Mobile has not yet formally studied
savings, 'cost/benefit-wise, I think it's well, well
worth it,' Lyons said. Data from the system has led port
officials to hold off on allowing entry for a ship that might have
hit bottom and allow entry for a ship they might have otherwise
made wait for several hours. 'I'm a big fan of
it,' he said.
Lyons said the port spent $400,000 setting up the system, and he
estimates it costs about $100,000 a year to maintain.
'That's pretty minimal when you consider the benefits.
It's a real outstanding effort that NOAA has put forth. They
ought to have them everywhere.'
Wright said there are plans to bring an additional six ports
into the system during the next year.
And NOAA is looking to improve PORTS as it expands, starting
with data delivery. First, Wright said, program officials are
looking at alternative transmission media. Negotiations are under
way to provide access to the Iridium network of satellites, which
would allow direct transmissions from some remote sensors to the
satellite. Wright said the program also is looking for ways to
reduce message sizes. All these efforts are directed at increasing
the amount of data that can be provided to mariners in as close to
real time as possible.
NOAA also is working to provide access to PORTS through the
Coast Guard's Automatic Identification System. 'They
use it in their vessel traffic service centers to monitor where all
the vessels are,' Wright said. 'In addition to just
monitoring, the data is transmitted out to all vessels in the area,
and vessels that are equipped with an AIS receiver can also see
where all the other vessels are. It's really used for safety
of navigation, so everyone knows where everybody is. We're
working with the Coast Guard to get our PORTS data sent to the
Coast Guard, and they are going to broadcast it out to the all
vessels in that area.'
Lyons has another suggestion for improving PORTS. 'About
the only thing it doesn't have that we would love to have is
a wave height indicator,' he said. 'We hope that
they're going to find a way to include that in the system in
the future. It would be useful to have, offshore, a wave height
indicator so that the pilots can more accurately determine at what
point they need to quit boarding where it's not safe.
'Secondly,' he added, 'we do a lot of
intercoastal traffic going over to Mississippi Sound as well as
over into the eastern Gulf and the coastal waterway over toward
Pensacola, [Fla.], where wave height can make a difference for
inland barges ' transiting. Sometimes maybe they're
holding back when they don't have to.' ■