This is the third section of a four-part article dealing with the volcanic eruptions in the Westman Islands, south of Iceland in the decade from 1963 to 1973. Part one covered the eruption of the volcano Surtsey in 1963, and my visit to the island in 1970 (WAT ON EARTH, Spring Issue 1997). Part two covered the early days of the eruption of Eldfell on Heimaey in 1973 (WAT ON EARTH, Fall issue, 1997). In this issue I will describe the continuing eruption until the cessation of activity in 1973. The final section scheduled for the fall 1998 issue of WAT ON EARTH will cover events on the island from 1973 to date. Just out of interest, as I am typing this article I am also re-living the eruption on my computer screen watching a "mini-view" of the Heimaey Eruption film, that I have placed on CD-ROM running in the corner of my screen.
As in the last issue, I will provide some personal accounts taken from my diary and then provide a more "detached" analysis of what was happening during this six-month period. By mid-April I was back on the island. Unfortunately teaching commitments at Waterloo and the lack of personal funds prevented me from staying on the island on a permanent basis. I had seen the eruption practically from its inception into the early days of February, and I had left the island with the feeling that although things were not going too well, the Icelanders were not going to roll over and quit. Well, things did not go too well in February, or in March for that matter, and April - well - but perhaps I am getting a little ahead, let's pick up the story in mid-April.
Grey, overcast, cloudy skies, Reykjavik in April. The rain rippling in concentric circles on the black cinder runway and the smell of kerosene in the air. Another delay, a two-hour hold on departure because the airport at Heimaey is still closed with bad weather. Eventually we took off. The aircraft was Gullfaxi a DC-3, which had undoubtedly seen better days. As we passed over the low hills outside Reykjavik I wondered if it was the same aircraft that had taken us to Heimaey in that blue August morning in 1970.
We crossed over the coast, the line of breakers marching away toward the east - toward Dryholay and Vik. Fifteen minutes later the first of the Westman Islands appeared below, black, in the leaden grey-green sea. Moments later the wing tilted and the south end of the high cliffs of the western crater slid past, the waves breaking in two large caves near the base. A quick blurred view of the town writhing in white steam, and then with a bump we were on the end of the runway. Fifteen minutes later we were on the way into the town. My "home" was to be the Hotel HB, reserved for "rescue workers" and visiting scientists. Less than an hour after I had landed I joined a Norwegian reporter and we started into the town.
The streets were blocked with tephra and we soon encountered a wooden barricade labelled "Haetta - Danger: - no admittance". We had been informed about the barriers, which had been put in place the previous month when gas concentrations built up. We skirted the barrier and walked swiftly toward the center of the town. At the end of the street I could see a wall of lava, just beyond the bank. It appeared to be almost twice as high as the houses, rising perhaps 20m above street level. We turned up toward Astuvegar, the house on the corner now almost buried with ash - the garden walls had disappeared. Up the street piles of black ash told the story of bulldozers clearing blocked roadways. The signpost at the top of the street had completely vanished and across the road the rooftop that had stood forlornly above the ash plain in January had also partially disappeared. Someone had dug down through the tephra to the front door, a great ramp penetrating perhaps 4m deep. We turned and walked back through the town stepping over black rubber snakes, the high-pressure water lines leading from the harbour to the lava. Behind us Eldfell still grumbled casting a red glow over the steam rising from the lava front. I returned to the hotel at midnight the sky behind me lit up with the cherry-red glow of the volcano.
Figure 1. The last major advance of lava into town was on April 1. This was one of the last houses to be destroyed in late March.
The following day I started off back near the bank. The lava presents an incredible spectacle, huge blocks lie twisted and broken where they have fallen away from the front. At the base is a house, crushed and broken, venetian blinds splayed out through the shattered front window. The washing line in the back garden buried in black ash. The height of the lava front seems to bear testimony that the cooling of the lava appears to be working. I left the house and walked to another. Just inside the doorway, untouched on the countertop, a dessert (apple crumble) made by someone probably on that fateful night in January. Next to it a box of sugar lumps and a jar of Nescafé. In the front room the telephone was still plugged into the wall, some Christmas decorations stood in a pile in the corner, a broken coffee table and an abandoned organ were all that was left.
Down the street I walked over a roof and descended into the lower part of Kirkjuvegar. Two things caught my eye. Over the tops of the houses I could see the blue flag of Iceland with its red and white cross. Barely two hundred metres from the lava front it indicated the defiance of the islanders. At my feet the first green grass shoots were poking through the ash, the lava front here was only 50 metres away. Kirkjuvegar was blocked with lava. Vehicle tracks ran down the street and vanished beneath the lava front. I went over yet another set of rooftops and emerged onto the roadway at Midstraeti. Here the roadway has been driven up onto the new lava. There was a sudden roar behind me and emerging from the low cloud and steam was a lorry taking more ash to construct a roadway into the centre of the lava field.
Well, perhaps this is enough to give you a feel for what was happening in mid-April. But what had happened earlier?
When I left the island in the early days of the eruption, over 40 houses closest to the volcano had been lost. The lava flows were starting a slow march toward the centre of the town and bulldozers were fighting to create barricades in an attempt to divert the lava flows from the harbour approaches and the centre of the town. During the first two weeks of February more houses succumbed, and then a major setback. As so often happens in cinder cone eruptions, the lava welling from the side and base of the cone caused a massive slope-failure on the flank of Eldfell that allowed a surge of partially solidified tephra to overwhelm the man-made barriers. With the barriers gone, the lava flows moved directly toward the centre of the town. Unfortunately it also moved to the north shearing the electricity cables from the mainland and one of the two water pipelines also coming across the sea-floor from southern Iceland to Heimaey. More alarmingly for the Icelanders the harbour approach was now limited to a 200m wide channel. A few weeks earlier it had been almost one kilometre wide.
This setback caused the Icelanders to rethink strategy. There was now a reality that the centre of the town and the main fish plant as well as the harbour and port facilities could be overwhelmed. Some $2m worth of fish products were airlifted out, major processing equipment was removed from the fish plant and the rescue workers concentrated on stopping the flows using a technique tried briefly on Surtsey - fighting the fire with water!
Cooling efforts on the lava front had commenced in early February, but it soon became obvious that in order to provide a concerted effort to slow the lava advance this technique would have to be conducted with more than the town's fire hoses. Large quantities of lava were flowing from the new vent. During February and March the island expanded by almost 2 km2, with some flows reaching speeds of one metre per minute. The Icelanders purchased 38 large diesel pumps that were principally located along the inner harbour breakwater. They forced seawater through 30cm diameter plastic pipes to the lava fronts. In some cases the pipelines snaked almost 1.5 km through the town and onto the lava front. After being dragged into place by teams of rescue workers they were cut and spliced. Valves were attached to smaller fire hoses and the seawater was directed into fissures in the lava. The object of the exercise was to cool the leading edge of the advance. Once the temperature dropped by 200 degrees C, the lava front solidified. This acted as a temporary barrier and more cooling was conducted, gradually thickening and stabilising the front in an attempt to divert the flows in a different direction.
The one thing the Icelanders did not want to see closure of the harbour entrance. As mentioned above this was getting very narrow, and so a boat was brought in during late March to cool the seaward advance across the harbour approach. For a while in late March it appeared that this battle was lost. Major lava advances at the end of March
Figure 2. The water pipelines ran from the harbour, snaking through the town, eventually emptying into the crater of Eldfell.
consumed dozens of homes and business. On one day 60 houses were lost, and then the tide turned. The last big flow into the town occurred on April 1, and it was not too soon. The Icelanders were now directing the cooling efforts from the back wall of the fish plant onto the edge of the lava, and before the flow stopped it actually crushed its way into the rear rooms of the factory which was on the waterfront in the centre of the town! Whether it was a result of the heroic defence established by the citizens, or, in my opinion, a more fortuitous "diminution and diversion" of lava coming from the vent, the Icelanders won the battle to save the fish plant and the harbour. However, the house and business casualty listing was high. Over 300 homes and businesses were destroyed and 75 more were buried under large thicknesses of ash in the eastern suburbs of the town. The lava field averaged about 30 to 35m and in places it was over 80m thick. Even though the lava flows had stopped advancing into the town Eldfell was still very active with huge lava fountains interspersed with ash-rich blasts that were really exciting to witness.
Tephra thicknesses were considerable in eastern Vestmannaeyjar. Many buildings were partially or completely buried in ash, which was up to 6 or 7m thick in places. In February and March gas also started to become a problem. Concentrations of carbon monoxide and carbon dioxide were lethally high at times. Methane and sulphur dioxide also were recorded in high amounts. On calm days these gases were monitored very carefully and if concentrations approached danger levels the town's fire sirens were sounded. Rescue workers were then to get to high places (upper floors of houses or rooftops) until they could be evacuated, or until gas levels dropped. The one fatality of the eruption took place at this time with a person who was overcome by gases in the basement of a building.
The eruption appeared to cease just over 5 months after it had started in the last few days of June. A huge effort had been made to save the town because it is one of the very few safe harbours along the south coast of Iceland. It was also an extremely important fish-processing centre, responsible for almost 11 percent of fish exports from Iceland in 1972. In 1973 (the year of the eruption) the town had expected to process about $20m (US) in fish exports. The eruption saw one fish plant destroyed and two others damaged. As soon as visible activity ceased a major effort commenced in cleaning the town. (In fact this went on all through the eruption, and it was not unusual to see rescue workers, sweeping streets and clearing gardens even in the middle of the eruption). In late June and July people were seriously thinking of returning to Heimaey. Students joined the rescue workers and the streets were cleared. Gardens were excavated and new plants established, house walls were washed, steel sheeting used to deflect pyroclasts in the early days of the eruption were removed, and new paint was applied to refresh ash-blasted facades. By mid-July most of the Heimaey trawler fleet, which had been sent to other facilities throughout Iceland, came back to their homeport. About the same time forty families arrived back on the island and the island started to return to normal.
Figure 3. The lava flow was finally halted inside the back rooms of the fish plant on the quayside in the centre of town.
Figure 4. The harbour approach. The centre of the fight with Eldfell was to keep the harbour entrance open. This photograph, taken in early July, shows that the battle was won.
But, of course, things could never be quite the same. Heimaey had a second volcano only a few metres lower than Eldfell, and the twin cones dominated the view of the eastern part of the town. Many islanders said that this new configuration provided more shelter for the town when the northeast gales blew during the succeeding winters. The huge quantities of ash that had been ejected were removed from much of the eastern part of Vestmannaeyjar and were used to provide new house foundations in the area north of the airport. Part of the estimated 20 million tons of ash were used to extend the airport runways. The Icelandic Geothermal department commenced an evaluation of the new lava field to see whether it would be practical to build a heating system for the island (it was). Finally plans were laid for the new suburbs and social structures, such as the swimming pool, to replace those destroyed during the eruption.
My personal view is that this eruption did more than change the lives of people on Heimaey. It also changed my life. During the eruption I had carried a Bolex 16mm camera and a very large tripod to film different aspects of what was happening. Eventually the pieces of film were put together during 1973 and 1974. Having spent a large amount of personal finances to travel to and from to the island I decided to try to recoup some of the losses by producing a film of the eruption. This was eventually mixed in 1974 and appeared as a "Nature of Things" documentary on CBC entitled "The Heimaey Eruption: - Iceland 1973". It also led to my introduction to public awareness of science activities and to the support of those who are attempting to show the validity of their research and teaching interests to the public at large. In the next issue of WAT ON EARTH I will provide information on what has happened on Heimaey in the 25 years since the eruption.
Alan V. Morgan