Dozens of seized superyachts may cause significant environmental damage if governments fail to pay millions in maintenance costs, experts say

• The seized yachts of sanctioned Russian oligarchs are in limbo as European authorities decide next steps.
• Experts say that without maintenance, the yachts could quickly become an environmental hazard.

Dozens of superyachts seized from Russian oligarchs could pose a significant environmental threat to marine life and surrounding environments if they are not maintained — a process that typically costs millions.

Earlier this month, Italy seized a $578 million megayacht belonging to Andrey Melnichenko, France seized a $120 million vessel owned by Igor Sechin, and Spain seized a $153 million superyacht linked to Sergei Chemezov. More recently, the UK detained a $50 million superyacht, whose owner remains concealed.

Insider spoke to three experts that said the superyachts have the potential to wreak havoc on the environment if the governments that seized them choose to let the vessels go without daily maintenance.

"Abandoned ships are an environmental hazard," Anna Barford, the Canadian Shipping Campaigner at the environmental group Stand.Earth, told Insider. "As the vessel breaks down contaminants leak into the marine environment."

Determining responsibility for maintenance costs

According to Benjamin Maltby, a partner at Keystone Law in the UK and an expert in yacht and luxury asset law, the maintenance cost of a yacht usually totals about 15% to 20% of its overall value. For Melnichenko's yacht, for example, that would translate to up to $115.6 million in annual expenses.

Even foregoing the costs to staff, repair, fuel, and insure the ship, the fees to dock the yacht can quickly add up. Todd Roberts, president of Marine Boat Works in California, previously told Insider that docking alone typically costs tens of thousands of dollars per month.

Whether the asset is detained, seized or arrested, the maintenance costs will fall on the owner, Maltby said. However, there is a duty of care that comes into play as soon as any authority detains a possession.

"Under English law, you are under a legal duty of care," Maltby said, noting that an authority will become a bailee, an individual who temporarily gains possession, but not ownership, of a good or other property.

"I think it would be embarrassing for the various European governments that seized the yachts to not take care of them," he said.

Environmental hazards

Crew members are essential to a superyacht's maintenance, for everything from washing the bow of the ship to technical maintenance. An unmanned ship could rapidly waste away and deteriorate in a matter of weeks.

According to Barford, if the superyachts are left without proper care, the local marine ecosystem could face any number of issues, from sewage leaks to industrial waste.

"If sewage is not properly maintained, it can have a fail rate of over 90%," she said. "That means you have gray water, raw or improperly broken down sewage leaking into the water. It can cause issues for fish, spread disease, even acidify the ocean to a degree."

Maltby added that another possible long-term risk is "accelerated galvanic corrosion," which English marine biologist Jannah Kehoe described as a phenomenon in which two different metals come in contact with each other and with an electrolyte which, in this case, is seawater.

"These conditions generate an electrical current and cause one metal to break down faster than the other, and will commonly cause the steel hull of a ship to break down if untreated," Kehoe said.

The corrosion can be extremely harmful for the environment. According to Barford, it could contaminate the water and cause plants and other marine life to die because either they cannot metabolize the industrial waste or it will get passed on through the food chain.

It could even get to a point where humans come in contact and consume contaminated fish or oysters from the site, she said.

Ultimately, the best move to avoid the deterioration of the yachts and local marine life would be to dry dock the yachts, but the process would be expensive, Barford said. It would require an intensive cleaning process, as well as the use of heavy machinery to lift the yachts out of the water and transport them to a new location.

The yachts could also lose their certification if they are not maintained, meaning they ultimately could lose their insurance, as well as any ability to cover costs in the event of serious environmental hazard such as an oil spill.

"Normal operations already have a negative impact on marine life," Barford said. "When you factor in an essentially unattended ship, it only gets worse."