{"id":21499,"date":"2017-07-04T11:35:15","date_gmt":"2017-07-04T09:35:15","guid":{"rendered":"https:\/\/www.ferrovial.com\/blog\/es\/?p=21499"},"modified":"2025-12-12T11:23:19","modified_gmt":"2025-12-12T10:23:19","slug":"hawaiian-volcanoes-effect-on-roads","status":"publish","type":"post","link":"https:\/\/www.ferrovial.com\/blog\/en\/2017\/07\/hawaiian-volcanoes-effect-on-roads\/","title":{"rendered":"Building roads under the eye of the volcano: when asphalt and lava come together"},"content":{"rendered":"

Coconut palm beaches, crystal-clear waters, thick jungle, little-known animal species, ukuleles and the spirit of Aloha<\/em>\u2026 Hawaii conjures up myriad different images in our minds. However, there is one thing that we invariably associate with this isolated archipelago lying in the middle of the Pacific Ocean: its volcanoes<\/strong>.<\/p>\n

The close to 400,000 inhabitants of the remotest islands on the planet have been learning to live side by side with nature at its wildest centuries<\/strong>. Earthquakes, tsunamis and fierce storms regularly batter the archipelago. But what really marks Hawaii\u2019s destiny, day after day, is lava. And perhaps the best way to understand this is through its road network.<\/p>\n

Mauna Loa, standing 4km in height, is the Earth\u2019s tallest volcano, and Kilauea the most active, with 35 years of uninterrupted eruptions<\/strong>. These two are the most famous, but there are many more. In fact, the island has 20 volcanoes, both active and dormant; 30 if we also count those on the atolls and furthermost archipelagos, or 80 if we count the Hawaiian-Emperor seamount chain<\/a>, of which the islands are the visible part.<\/p>\n

Rivers of a relatively liquid lava cross the islands, destroying everything in their path and changing direction seemingly at will until they enter the sea. From one day to the next, a whole village may be cut off and all access roads buried under several metres of lava. So how do the people in Hawaii keep their road network open? How can asphalt coexist with molten rock?<\/p>\n

\"hawaiian<\/a>

In 1973, a river of lava again covered the Volcanoes National Park road \/ USGS, RL Christiansen<\/p><\/div>\n

Volcanoes mark the trend<\/strong><\/h2>\n

Kilauea is the second youngest of the Hawaiian volcanoes, at close to half a million years. It is also the most active and the one that has brought the greatest danger in the island\u2019s recent history. The Pu\u2018u \u2018\u00d6\u2018\u00f6 crater started spouting lava in 1983 and has never stopped.<\/strong><\/p>\n

Since then, unpredictable rivers of lava have been constantly flowing down the slopes and moving towards the ocean, posing enormous challenges for the district of Puna, one of the most densely populated areas on the southwest of Hawaii\u2019s main island. Since 1983, molten rock has buried more than 200 houses here<\/p>\n

And this is where the work of the USGS Hawaiian Volcano Observatory<\/a> shows its worth. The Observatory regularly issues a report on the state of the eruption, the direction of the lava flow, its speed and the risks involved. In addition to this public information service, technical staff use cameras and sensors<\/a> to monitor the eruption 24\/7, and draw up risk maps based on the data recorded.<\/p>\n

\u201cThe episode 61g flow [uninterrupted now for a year] remains active and is entering the ocean at Kamoukuna\u201d, explains the last update available. \u201cThe flows pose no threat to nearby communities at this time\u201d. But it was a different story in the summer of 2014<\/strong>.<\/p>\n

\"hawaiian<\/a>

Lava flow from Kilauea entering the ocean \/ USGS<\/p><\/div>\n

On 27th June, a new eruption of Kilauea decided to head for the district of Puna. For days it disappeared underground, advancing through some of the many subterranean volcanic galleries criss-crossing the island, only to reappear on an even more dangerous path. In September, the town of Pahoa started preparing for the worst, as the incandescent lava flow approached highway 130, used by an average of 15,000 vehicles per day<\/strong>.<\/p>\n

However, the lava never made it to the main road, instead deciding to change direction at the last moment, although it did block secondary roads, now solidified as large basalt walls around the town. Despite the happy ending, the incident tested out the island\u2019s state of emergency preparedness<\/strong>.<\/p>\n