Ship Wrecks as Ticking Time Bombs: Interview with Dr. Matt Carter

April 29, 2020Interviews

It has been exactly ten years ago since the disastrous explosion of BP’s “Deepwater Horizon” oil rig. This incident caused a large-scale environmental catastrophe, leaking an estimated 3.19 million barrels (over 130 million gallons) of oil in the Gulf of Mexico. However, oil rigs are not the only dangers to the environment in terms of possible oil leakage.

Over 3000 ships sank in the Pacific during WWII, including about 300 oil tankers. As they rust, many of them are starting to leak oil. Several Pacific Island communities are worried that major oil spills from other wrecks will soon devastatingly pollute the reefs and mangroves of their coasts. But very little is known about which wrecks are ticking time-bombs and which wrecks have already lost their oil. 

We spoke to Dr. Matt Carter, a maritime archaeologist and the Research Director for the Major Projects Foundation. He is an International Fellow of the Explorers Club and has worked on, and led, maritime archaeological projects in 12 different countries.

Dr. Matt Carter
Dr. Matt Carter, Research Director for the Major Projects Foundation

Why do ship wrecks spill oil?

Ships are not designed to withstand the forces of being submerged underwater for a long time, as well as the process of corrosion that comes with this. Our only way to stop oil leakage is to remove the oil before they sink or once they reach the bottom. The key is to get the oil while it is still contained.

However, every ship sinks differently. Some ships sink to the bottom with parts or even all of their fuel tanks intact – over time, a wreck may corrode, and eventually, the oil starts to leak slowly. Or a wreck may collapse directly, which can lead to a much more massive spill. 

The vast majority of potentially polluting wrecks around the world date from WWII, and now after over 75 years, they are at the very end of their lives. It is estimated that in the next 5 -10 years, many of those wrecks will suffer structural collapse releasing all the oil they still contain.

How do underwater oil spills affect our environment? What are the immediate effects on the environment close to a spilling shipwreck? 

It depends on the type of spill. If oil is “only” leaking slowly, then it can chronically poison the ecosystem around the wreck. If it is a more significant release, then the damage can be much more widespread. To say the least, science is clearly stating that oil spills are negative for marine life. 

Major Projects Foundation Diver inspecting ship wreck
Major Projects Foundation: a diver inspecting a ship wreck.
Photo Credit: Steve Trewavas

Additional Info:

Oil in the Ocean poses many dangers for marine life. Many birds and fur-bearing mammals lose the insulating qualities of their fur and are thus exposed to the cold and harsh elements, possibly dying from hypothermia.

Sea turtles can get trapped in the oil and mistake it for food, poisoning them. Inhaling oil, as dolphins and whales can do, affects the health of their lungs, their immune function, as well as reproduction.

Fish experience “reduced growth, enlarged livers, changes in heart and respiration rates, fin erosion, and reproduction impairment.”

Globally, how many leaking shipwrecks are out there? And how many are considered “ticking timebombs”? 

Globally there has been an estimate of around 8,500 potentially polluting shipwrecks. As only a fraction of these wrecks have been investigated, we simply don’t know how many of these pose an immediate or future threat and which ones aren’t. 

The Major Projects Foundation focuses on the potentially polluting shipwrecks in the Pacific, where we have narrowed down the list of over 1200 to 53 ‘Category 1’ wrecks that are deemed the highest potential environmental risk.

Sea life nesting on Ship Wreck
Sea life evolving directly on sunken ship.
Photo Credit: Steve Trewavas

The ranking system takes into consideration…

  • … the variables of cargo (loaded tankers, for example, are given highest priority),
  • … the propulsion system (motorships or oil fired streamers are given much higher priority over coal powered steamships),
  • … the type of vessel (tankers are given highest priority over other vessels),
  • … its size (the larger the vessel, the higher the priority),
  • … and where the vessel sank (vessels that sank in shallow waters are given a higher priority to ships in deep water)

Category 1: is representing the highest potential environmental risk; 

Category 2: medium but increasing potential environmental risk; 

Category 3: low but increasing environmental risk; 

Category 4: not considered an environmental risk as in very deep water (where water pressure congeals the oil) or wreck has been heavily salvaged and/or has had oil removed;

Category 5: no risk whatsoever as ship fully salvaged post-war.

How do you identify those shipwrecks and where do the difficulties lie?

We identify those through historical research, mainly of English-language and Japanese archival material, as well as through talking to the people who have dived those wrecks.

The problem is, that there are thousands of these wrecks around the world and narrowing the list to the ones that are the highest risk is a combination of historical research and survey either through diving or ROV.

There is a lot of work to be done and it is very time consuming. In the USA, UK and Europe there has been Government support and they have made some really good progress but there has been practically nothing done in the Pacific and no government support. The key difficulty is resourcing – the more support we get the more staff we can direct toward the research and fieldwork. 

From identifying a wreck to ”sealing it shut,” what’s the general procedure of such a project? 

It is a multi-stage process. First, the wrecks need to be identified and then surveyed if they are deemed an imminent risk. Then, the wreck can be pumped out, meaning that we drill holes into the tanks and remove the oil. We are still in the early phase of our mission where we are identifying and surveying the wrecks.

How do tools like video recording or photogrammetry help your work? 

Video survey allows us to get an overall idea of the condition of the wreck and understand how it is corroding and what species of marine organisms have colonized the wreck.  

Photogrammetry is another useful tool, which allows us to take thousands of photos of a wreck and turn them into an accurate 3D model from which we can understand the exact condition of the wreck and even take measurements. We can also overlay the original plans of the ship over the 3D model to see exactly where the fuel tanks are to see which ones might have been ruptured in the sinking or from corrosion. 

3D Model of Ship Wreck
3D model of a shipwreck.

Are there ways regular divers can help? 

Absolutely! With so many potentially polluting wrecks around the world, we are very keen to work with divers who are out and diving these wrecks so that we can get the information we need to prioritize which ones are leaking and which will leak in the future. 

Taking video of shipwrecks that are a potential threat, and uploading those videos to the Paralenz App helps us in our mission to remove these threats before it is too late! 

Thank you, Matt!

About Major Projects Foundation

Paralenz partner Major Projects Foundation (MPF) is a marine research and conservation not-for-profit organisation with a focus on deploying engineering solutions to protect ecosystems and cultural heritage in the Pacific.

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