Huge oil tankers call at the Port of Long Beach regularly, but never with a full load.
These massive vessels carrying up to 2.5 million barrels of crude are partially unloaded offshore before coming through the Port's Main Channel to dock at Tesoro’s deep-draft terminal at Berth 121.
Although the channel is 76 feet deep, there was no way to predict how close a ship could come to touching the bottom. These giant vessels are longer than three football fields, and if they sat on dry land would be taller than a six-story building.
What if westerly waves caused the bow of a 1,100-foot long tanker to move up and down? One degree of pitch could mean 9½ feet of increased draft. That’s why the maximum draft for tankers entering the port is 65 feet.
But thanks to a new predictive program being tested by Tesoro, port pilots now possess a significant tool that can measure the actual motion of ships to determine whether they can safely navigate the Long Beach channel, allowing tankers to arrive with deeper drafts and heavier loads.
The system consists of an instrument — called an “octopus” — that pilots put on ships to measure movement. There are also three local and three offshore buoys with technology that measure wave motion, direction and height. All this information is entered into a computer that synthesizes the data to predict a ship’s roll, pitch and under-keel clearance.
Being able to bring these supertankers to dock means less pollution, less congestion and better use of port infrastructure, said Captain Rob McCaughey, Manager of Marine Operations at Tesoro.
“This is ultimately going to reduce the risk of transferring oil on the West Coast,” he said. “Every VLCC [very large crude carrier] that we can bring in fully loaded, it’s four or five ships that are removed from the water and not emitting emissions in the atmosphere. So it's huge.”
The octopus technology could also be used on container ships, drilling, and in the industry as a whole, McCaughey said.
“There's a lot of organizations now that are looking at this technology,” he said. “This is the first of its kind in the U.S. There's a tremendous amount of benefit for this project.”
Port pilots on board
The idea for a pilot program began in 2012, not long after Tesoro took over BP's assets at the Port of Long Beach.
Officials at Tesoro and Jacobsen Pilot Services started talking about technology that could help predict the draft clearance of these supertankers. So a Jacobsen representative traveled to Rotterdam — whose channel is similar to Long Beach’s in depth — and observed pilots using Protide, a predictive system also used in Amsterdam and Germany.
The Port of Long Beach and the state agreed to share the cost of a $50,000 study into Protide, and Tesoro proceeded with the program in 2014.
Before a ship comes through the channel, Tesoro and the pilots go through the Protide results. Then they board the ship and hitch the octopus to a laptop on the bridge.
Once the ship’s motion is recorded, the pilots take that information back to the pilot's station, plug the data into the Protide computer and superimpose the actual results onto the predictive information to see what the ship actually did versus what it predicted the ship would do.
“We've been very methodical over the last year, going through every little step,” McCaughey said. “If it came out close to the program, it was a successful test, and for the most part they were very, very, very close.”
After testing 30 ships, Tesoro agreed in late 2016 that they were ready to bring in a supertanker at 66 feet and the first VLCC under the new system, the Gem 2, entered the channel in early April.
The plan to expand the draft limit is being implemented in four phases, with each phase taking ships a foot deeper than before. In the final phase, a VLCC would be able to pass at 69 feet, the deepest draft a ship at which can be brought in by regulation.
All this would be accomplished while still maintaining at least 10 percent of clearance at all times, McCaughey said.
In early May, Tesoro agreed to move to Phase 2, at 67 feet. If everything goes smoothly, Tesoro could reach 69 feet by the end of the year, McCaughey said.
But there’s no desire to rush the process. In fact, additional safety measures have been added to hedge their bets.
For example, if the program predicts 2 feet of keel clearance with all the motion, Tesoro and Jacobsen set a “hard deck” or clearance of 3 feet. If the program predicts that the ship's going to get within 3 feet of the bottom, clearance needs to be greater than 3 feet, McCaughey said.
If pilots don’t feel comfortable bringing in a VLCC through the channel, they will wait for more favorable conditions.
“This Protide system is just a tool to enable us to see what the ships are actually doing, but we're not only relying on that program to tell us this is what we're going to do,” he said. “We still have what I usually call the seaman's eye. We take our experience in the mix.”
Several agencies are supporting Tesoro’s project, including the U.S. Coast Guard and the National Oceanic and Atmospheric Administration, which is hoping to use the technology to create an inshore wave model for Southern California.
“We believe that this first-of-a-kind capability in a United States port will leverage emerging technologies to better protect our sensitive coastal environment, by reducing the number of offshore oil transfers from supertankers to smaller ‘lightering’ vessels,” said Thomas Cullen, Jr., administrator for the California Department of Fish and Wildlife.
The Port of Long Beach celebrated Tesoro’s success.
“The Port applauds Tesoro and Jacobsen Pilots’ ability to safely move supertankers through our channel,” said Long Beach Harbor Commission President Lori Ann Guzmán. “It is one example of how the Port continues to pursue ways to increase business in a sustainable manner.” Photo captions: In April, the tanker Gem 2, top, arrived with the deepest draft of a vessel, 66 feet, to enter the Port of Long Beach. Above right, the crew and Tesoro and Port officials mark the occasion; a vessel with a 67-foot draft has already surpassed the record, thanks to the "octopus" system.