It was unexpected. The scientists had not noticed any warning signs. There were no data to presage the onset of the eruption . On January 23, 1973, a previously unknown fissure in the Earth below the small Icelandic island of Heimaey opened less than 2 kilometers from the town of Vestmannaeyjar, which had about 5,000 inhabitants at the time. It was just after 2 in the morning and all the inhabitants were fast asleep. They woke up with a start. It was the Eldfell volcano that had erupted. The fissure, almost 2 kilometers long, located near the town, began to spill hot lava in the direction of the town.
The island on which the volcano erupted is part of an archipelago of 15 islands and some 30 volcanic piles off the southern coast of Iceland. The islands are part of an active volcanic system, formed in less than a hundred different eruptions over the last 15,000 years.
The island of Heimaey is the largest of the Vestmannaeyjar Islands and was home to a thriving fishing industry, a hub for trawling.
The volcano woke up
At first, the first eyewitnesses thought that the houses were burning due to a fire, until they realized how the lava was thrown tens of meters into the air. The tongues of lava began their descent down the mountains. The authorities did not take long to evacuate practically the entire island safely (by fishing boats that took them to the mainland) but, in the face of the advance of the lava, which was destroying hundreds of houses in its path, it was preparing the way, slowly but surely , towards the port of the city, one of the most important fishing ports in Iceland. It would end everything. And it was the main source of income for the island. The water temperature rose to 44ºC.
Could something be done?
The port had to be saved somehow. Although the advance of the volcano’s flow heralded the destruction of the entire city, the engineers of the time devised a desperate operation: pumping sea water and trying to cool the volcanic lava in order to stop its advance.
What happened?
The eruption threatened to engulf the town, but the titanic effort to slow and control the lava flow by pumping seawater and spraying the edges of the streams was successful. Emergency personnel who had not left the island began fighting the lava flow using more than 30 kilometers of pipes and 43 water pumps. They pumped more than 6 million cubic meters of seawater into the advancing lava flow. The lava flow towards the harbor slowed down and eventually stopped. The operation began in February and ended in July of that year. It was something unique.
The lava added 2.2 square kilometers to the island, growing from 11.2 square kilometers to 13.14 square kilometers.
The eruption continued for five months, producing not only lava but also more than 1.5 million tons of ash that buried the city. More than 800 houses were destroyed by tephra or engulfed by lava when the eruption ended on June 28, 1973.
A year after the end of the eruption, most of the residents had returned to the island and it is still happily inhabited today.
