María Elena Lacilla
Professor of Urban Planning at the School of Architecture
The Cumbre Vieja volcano, which has been erupting since 19 September, was the cause of two other similar events in the last century. Among them was the eruption of Teneguía in 1971, which created 200 hectares of new land for the island. Today, with the lava already in the sea, the natural catastrophe has left behind more than 1,000 damaged buildings over an area of some 300 hectares. Although it is still unclear when and how the event will end, there are very important issues that are already being addressed, such as land ownership and land rezoning, the relocation of people whose homes have been swept away by the lava flow, and the new landscape created by the eruption.
Under the property regime, the land that the volcano's lava gains from the sea will automatically become "public maritime land domain". In the meantime, properties buried on land by the magma flow will remain private. However, the owners will no longer be able to build on them, unless the geological or historical heritage is modified. In fact, it is most likely that these hectares engulfed by the volcano will be declared a protected area, as the State is obliged to protect this new property, which is part of the geological heritage and therefore subject to the Law on Natural Heritage and Biodiversity. In doing so, the State may or may not expropriate the affected properties.
Specifically, the Law on Natural Heritage and Biodiversity recognises the heritage value of a variety of geological elements, including rocks, minerals, fossils, soils, landforms and geological units and landscapes that are the product and record of the Earth's evolution. In this sense, José Barrera - an expert volcanologist from the Illustrious high school of Geologists - points out that it is up to the administrations "how to proceed with these properties: whether to exchange the land to its owners for new ones or to build a new village or town to relocate those affected".
At the same time, the real estate supply in La Palma is scarce, which makes it advisable to consider the construction of a new settlement with new buildings and dwellings of a similar size to those previously owned. The pending question, if this solution were to be chosen, would be to determine the location of the new settlement.
La Palma is regulated from an urban planning point of view by means of an Island Plan of a supra-municipal nature that deals with normal settlement forecasts, among other issues. It also deals with possible seismic risks due to the high level of activity on the island. As a result of what has happened, it seems pertinent to redefine the risks in order to then evaluate the location of possible settlements and, therefore, the requalification of land; as well as where to locate the construction of those dwellings that have been demolished. All of this requires the partnership of scientists, who could identify vulnerable areas in the environment deadline. While it is true that the eruption has occurred where it was not foreseen, the evaluation should be subject to scientific study.
It would be desirable to ensure that settlements - tourist, residential or agricultural - can be developed in places where the likelihood of risk is reduced. In other words, re-zoning should take place on land that guarantees precaution, based on the reports of geological experts, so that there is greater certainty that this land will not be affected by similar phenomena in the coming years. Likewise, another of the elements to be taken into account when defining a territorial plan, taking into account this natural event subject , should be the infrastructures, such as resource for evacuation and civil protection.
On the other hand, land that has been flooded by lava will lead to the creation of a new landscape, as happened in Timanfaya (Lanzarote). Another case that can serve as reference letter to glimpse the future of the Las Manchas area after the eruption can be the reality left behind by the eruption of the Eldfell volcano in Iceland. This volcano erupted on 22 January 1973. It remained active for almost six months and nearly wiped out the port of Heimaey: an urban settlement with almost 5,000 inhabitants and 11 mk2. The site was evacuated but a small group of people were left to fight against the lava and the destruction of the harbour, which was the main livelihood of the fishing village.
The group managed to stop the disaster thanks to a system of pipes that transferred water from the sea to the lava, a technique that had already been experimented in Hawaii in 1960, and which was used in Iceland not only to stop the margins of the lava flow and limit its expansion, but also to reach the largest possible surface of the language lava. The result of that natural episode left a new volcano on the mountain with a height of 225 metres, an area of 3.3 km² covered with lava and 13 km² more island.
After the catastrophe, Heymaey experienced a tourism boom that helped to revive Economics. The inhabitants gradually returned and several plants were built to supply energy to the island by harnessing the heat of the lava flows beneath the solidified surface. Today Heymaey is an important fishing and tourist community, and the village has fully recovered its population.