The Braer Disaster (Oil Spill)

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Contents

The oil spill

The Braer had a payload of about 84,700 tonnes of light Norwegian crude oil and some additional 2000 tonnes of heavy oil and diesel for her engines. Compared with other accidents involving oil tankers over the last decades these were relatively small figures: The Amoco Cadiz wrecked off Brittany in 1978 carried a payload of 227,000 tonnes ... but it was two and a half times more than known from the Exxon Valdez which sank with some 37,000 tonnes of crude oil in Prince William Sound, Alaska, in 1989.

Simulation of oil spill for the days from January 6th to January 21st, 1993

From that it was clear that Shetland had to face an environmental disaster which was to be regarded as the "worst case ever possible", but looking back we do have to admit that it could have been worse. Fortunately for Shetland, the Gulfaks crude loaded on the Braer is not a typical North Sea oil. It is lighter and more easily biodegradable than other North Sea crude qualities. This, in combination with some of the worst storms seen in Shetland, prevented the event becoming an even bigger disaster.

Ruined crops in an oil sprayed field

The storm and a longer lasting period of strong winds after the accident improved the natural dispersion of the oil by wave action and evaporation; in addition, they kept the mass of the oil along the southern coasts of Mainland and hindered a drift onto Shetland's coast further away.

On the other hand, the waves and the wind caused major problems which nobody had foreseen: a massive oily spray covering a big inland area and thus destroying field crops, affecting fresh water lochs and creating an incalculable risk to the health of both humans and animals.


An account of the first week

Tuesday, 5th January

Following the grounding at 11:19 hrs, a first aerial surveillance flight was underway by 2.45pm. Oil was observed drifting into Bay of Quendale from Garths Ness. No counter-pollution measures were taken at sea on this day.


Wednesday, 6th January

Day1.gif
MPCU Dakota spraying dispersant, 8th January 1993.

The next morning thick floating oil was reported for a stretch between Siggar Ness and Sumburgh with broken sheens in the West Voe of Sumburgh.

Sheens were also observed on the west coast as far north as May Wick by 3pm. The Marine Pollution Control Unit (MPCU) carried out a trial dispersant spraying in the morning. Some of the oil was successfully dispersed.

Later non-dispersed floating oil was sprayed but the operations ceased around 3.45pm.


Thursday, 7th January

The oil had reached the southern tip of Burra Isle on the west coast and Lambhoga Head on the east coast. A helicopter tried to spray a very small quantity of dispersant close to the wreck, but this had to be abandoned due to the adverse weather conditions.

A surveillance flight in the afternoon showed that the oil did not move further northward since the morning.


Friday, 8th January

The result of oil damage

Sheens of oil reached Scalloway on the west coast and heavy sheens were reported near fish farms in Clift Sound; light sheens were observed on the east coast, as far north as Mousa.

Weather conditioned worsened so that no spraying of dispersant took place but out on the open sea waves of up to 10m high dispersed the oil naturally.

The first light sheens were observed on Spiggie Loch. The loch, an important RSPB bird reserve, was contaminated by both oily spray and by surface oil during high tides. It was therefore protected by a boom. Later a sand and earth dyke were added to prevent further influx of oil.


Saturday, 9th January

Oil spill at January 9th, 1993 - The worst day

Saturday was the worst day following the incident with the maximum extent of surface oil movement observed during the spill.

It seemed that the Braer began to break under the pondering waves.

She released a new major spill of oil during the night which spread rapidly along the west and east coast of South Mainland.

Streaks of sheen had spread north to the southern coast of Bressay in the east and to the west off Weisdale Voe and Sand Voe on the west coast.

Saturday was the last day on which spraying from the MPCU Dakotas took place but 10 tonnes only could be sprayed.


Sunday, 10th January

No counter-pollution activity was carried out that day due to the strong gusts but considerable natural dispersion was observed.

There was only little oil on the sea's surface, except near the wreck.

Sheens were reported north of Fora Ness, on the west coast, and Lambogha Head, on the east coast.


Monday, 11th January

The vessel broke up during the day. A massive release of oil occurred during the afternoon and heavy hydrocarbon odour was reported as far north as Lerwick during the evening.

Again there was the fear of an explosion.

Surveillance flights using infra-red imagery had suggested that a large part of the cargo was still in the vessel until the ship broke up.

The extent of the oil on the surface was similar to the previous day, although heavy oil concentrations were reported between Siggar Ness and Sumburgh Head.


Tuesday, 12th January

The vessel broke into three parts and all of the remaining cargo was released.

Due to severe weather conditions there were no surveillance flights until 2pm.

From the flights considerable physical dispersion of oil were reported with a lot of brown foam in the surf zone along the west coast.


Wednesday, 13th January

Aerial surveillance on the 13th confirmed no change in the extent of surface oil pollution from the previous day.

Sheens and brown foam in the surf zone were less noticeable.


The days thereafter

Everything that happened to the Braer within the first week of her wreckage was due to the strong and gusty winds (for details see table below). Strong winds commanded the situation during the second week after the accident, too.

The winds got stronger and especially on the 13th and the 17th we saw extraordinary peaks even according to Shetland "standards" with gusts of 100 mph and above. The storms did not allow any anti pollution action on and over the sea but they showed extraordinarily positive results with regard to the natural dispersing of the oil.

The level of visible surface pollution declined throughout the second week after the grounding although there had been two minor spills of oil and/or some kind of hydraulic liquid on the 15th (see image to the left below) and on 19th January, 1993. Shortly after 21st January, 1993, all visible oil had disappeared from the sea but despite that pellets of emulgated oil and tar were washed ashore for weeks and months.


Oil spill at January 15th, 1993
Oil spill at January 21st, 1993
Wind Directions and Speeds
January 1993 Direction Average Speed mph Gusts mph
5th S to SW 45 90
6th WSW 35 88
7th SW 36 68
8th WSW 41 85
9th WSW 33 65
10th SW 35 91
11th SSW 40 71
12th WSW 34 71
13th (17th) SW 50 100


Regular surveillance flights by MPCU Dakotas continued until the 25th January, with Sullom Voe Terminal helicopter flights thereafter.

For more detailed information see the following Shetlopedia pages:

More pages about different aspects may be added later.

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