It was Good Friday, March 24, 1989, when the Exxon Valdez left the oil-loading station at the Trans-Alaska pipeline terminal for California. The 300-meter (984 feet) supertanker had 163,000 tones of crude oil on board. The helmsman navigated the ship safely through the Valdez straight, leaving Captain Joseph Hazelwood to take over command of the ship.

Because icebergs had been reported along the route normally taken by the ship, Hazelwood ordered the vessel to take a riskier, alternative route. Then he went to his cabin and got drunk, leaving one of his officers in command of the oil tanker.

That officer, however, happened to be the same helmsman who had maneuvered the tanker through the difficult passage, and he was overworked and tired. At four minutes past midnight, the tanker made a wrong turn, striking Prince William Sound's Bligh Reef off the southern coast of Alaska. Because a simple hull wall was all that contained the crude oil, there was no way of stopping it from spilling out.

The Alaskan ‘black death‘

At first the weather was calm. But the emergency boat on standby was out of operation, and even if it had been fit for use, it wouldn't have been able to stop the amount of oil spilling from the Exxon Valdez. As a result, for the first few days after the crash, no efforts were undertaken to stem the flow of oil into the ocean. More than 40,000 million liters of crude oil spilled into the cold Arctic Ocean water. Then a severe storm set in, ripping the oil slick apart. A section of slick made it to land, polluting more than 2,100 kilometers of rocky coastline. Another portion drifted away, and another sank to the sea floor.

The oil spill was devastating in many ways: It destroyed the gills and lungs of marine life and stuck to the coats of marine mammals and the feathers of birds, which froze to death or drowned because they are unable to swim. When the animals tried to clean themselves, they poisoned themselves - as they did when they ate food contaminated with oil.

One estimate put the number of seabirds that died in the first few days after the accident at more than 250,000 – another as high as 675,000.

Two hundred and fifty bald eagles were found dead, along with 3,500 sea otters. More than 300 seals died and 22 killer whales, along with countless mussels, starfish, crabs, crayfish, snails and bottom-feeding fish. Billions of fish eggs spawning the seabed of Prince William Sound were destroyed, and the phytoplankton did not survive the spill. The entire food chain was disrupted.

Oil still lurks beneath the surface

For those reliant on ocean fishing to make a living, their lives changed drastically from one day to the next. The entire region's economy collapsed.

A quarter of a century after the disaster, most bays in the area now appear to be clean, and most of the animal and fish species also appear to have recovered. But looks can be deceiving.

An estimated 80,000 gallons of oil are believed to have seeped into the ground, some of it in the form of highly weathered clumps of tar. What's dangerous is the part hidden under stones in layers of sand, preventing oxygen to enter and microorganisms to flourish. There, the oil has remained a thick, mayonnaise-like emulsion. Investigations by the US Geological Survey show the emulsion loosing none of its toxicity over time. The vertical layering of the rocks, however, prevents the sand from washing out to sea.

Twenty-five years after the tragedy, traces of hydrocarbons have been found in the tissue of mussels and sea bed organisms. In 2013, samples taken from the livers of ducks and sea otters revealed that they, too, continue to come into contact with the oil as they search for food.

Poison still lurking

Indeed, the recovery of sea life has been a mixed bag. Sea otters, for instance, appear to be rebounding and more humpback whales have been sighted in Prince William Sound than ever before. But the numbers of killer whales and seabirds remain low.

Herring eggs and juveniles died following the 1989 accident, which also weakened the adult herring population before it was wiped out completely in 1993 epidemic. Not only the herring fishing industry but also the entire ocean food change has suffered as a result. The large schools of fish that were once so plentiful in this ocean area are now history.

There are so many pollutants from the oil industry off the coast of Alaska today that one can no longer solely blame Exxon Valdez, making a long-term assessment of the effects difficult.

The question is: Is Exxon Valdez fully to blame? Or are the oil production, loading and shipping activities that have followed since then also responsible for today’s situation? No one seems to have an answer.

If anything good has come out of the Exxon Valdez disaster, then maybe that the accident happened early enough to have an impact on future plans for the Arctic oil industry. With greater oil drilling comes greater risks of contamination to the ecosystem.