Sea Empress oil spill
The Sea Empress oil spill occurred on February 15, 1996, when an oil tanker ran aground off the coast of Milford Haven in southwest Wales, releasing over 75,000 tons of crude oil into the sea. This incident became the third-largest tanker spill in United Kingdom waters and had significant ecological and economic repercussions. The oil spread rapidly due to adverse weather conditions, affecting a wide area, including parts of the Bristol Channel and extending to Lundy Island and the southeast coast of Ireland.
In the aftermath, immediate responses focused on assessing the environmental impact, implementing cleanup measures, and protecting local fisheries. A fishing exclusion zone was established to prevent the capture of contaminated fish, while mechanical and chemical methods were used to mitigate the oil's spread and clean affected beaches. Although local finfish populations recovered relatively quickly, shellfish faced more severe contamination and a slower recovery process. Extensive research conducted between 1996 and 1998 provided insights into the spill's long-term effects on marine life, revealing that while the immediate impacts were significant, by 2001, many affected populations had begun to recover. The spill highlighted the vulnerabilities of marine ecosystems and the complexities involved in responding to environmental disasters.
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Sea Empress oil spill
THE EVENT: Grounding of an oil tanker off the coast of Wales, resulting in the release of thousands of tons of crude oil into the sea
DATE: February 15, 1996
The Sea Empress grounding resulted in the third-largest tanker spill in United Kingdom waters, causing adverse effects to a number of wildlife species and considerable difficulties for the fishing industry within the region.
On February 15, 1996, the Sea Empress oil tanker ran aground on a wave-exposed, current-scoured section of coastline near Milford Haven in southwest Wales. Over the next six days, the vessel released more than 75,000 tons of North Seas light and about 400 tons of heavy fuel oil. Still leaking oil, the Sea Empress was recovered and towed to Milford Haven on February 21.
Weather and wave conditions that prevailed at the time of the spill facilitated the spread of oil slicks well beyond the immediate area of the grounding. Heavy oil slicks drifted into Milford Haven and also flowed north and south along the open Pembrokeshore coast. During the first weeks after the incident, oil was observed across a wide area of the Bristol Channel. More distant shores that were affected included those around Lundy Island and the southeast coast of Ireland.
Initially, the three main concerns were to establish the size of the area affected by oil, plan cleanup measures, and determine how badly various populations of shellfish, finfish, and other wildlife had been contaminated. Shortly after the spill, a fishing exclusion order was applied to the affected region, banning the catching of any fish within a designated area. Some of the spilled oil was mechanically sucked up at sea. Between February 17 and 25, large amounts of chemical dispersants were used to break up the oil into small droplets in order to reduce the to the coastline and to birds at sea. Mechanical methods were employed to clean beaches for the most part, but some dispersants were used to remove weathered oil from rocks next to selected beaches. The main recreational beaches were cleaned up by mid-April, allowing visitors to again enjoy them.
As local finfish were found to have little to no contamination, the ban on catching salmon and sea trout was lifted in May, 1996. The shellfish, however, were more heavily contaminated and recovered more slowly. Between 1996 and 1998, research was conducted to assess the impacts of the and the recovery of a range of key commercial fish species, particularly those that are important for food chains. By June, 1996, more than 6,900 oiled birds of at least twenty-eight species had been recovered dead or alive, and more than 3,000 birds had been cleaned and released.
Approximately one-third of the spilled oil evaporated from the sea surface, but because of a combination of natural and chemical dispersion, approximately 50 percent of the spill volume dispersed into the water column. The ultimate fate of this dispersed oil was unclear for some time, but water samples analyzed in 1997 showed low levels of total hydrocarbons. The impacts of the spill on the marine life in the area lasted for some years, but by 2001 the various populations appeared to have recovered.
Bibliography
Clark, R. B. Marine Pollution. 5th ed. New York: Oxford University Press, 2001.
Fingas, Merv. The Basics of Oil Spill Cleanup. 3rd ed. Boca Raton, Fla.: CRC Press, 2012.
"Oil Pollution Case Study: The Sea Empress." Young People's Trust For the Environment, 2024, ypte.org.uk/factsheets/oil-pollution-case-study/what-happened-to-cause-the-disaster?hide‗donation‗prompt=1. Accessed 24 July 2024.
Speight, Martin, and Peter Henderson. “Threats to Marine Ecosystems: The Effects of Man.” In Marine Ecology: Concepts and Applications. Hoboken, N.J.: John Wiley & Sons, 2010.