Why is there not a single bridge spanning the Amazon River, which is over 6000km long?

The Amazon River is the second longest river in the world , flowing through Brazil, Peru, Bolivia, and Colombia, and has the highest flow rate in the world, and is home to a valuable ecosystem, including a variety of fish and the endemic Amazon river dolphin . . However, even though the main stream of the Amazon River is over 6,000 km long and spans multiple countries, there are no bridges built, and the scientific media Live Science asked, ``Why on earth does the Amazon River This article explains the question 'Isn't there a bridge?'

Why are there no bridges over the Amazon River? | Live Science

There are nine bridges on the Nile River , the longest river in the world, in Egypt's capital, Cairo alone, and more than 100 bridges have been built on the Yangtze River , one of Asia's largest rivers, over the past 30 years. The Danube River is about one-third the length of the Amazon River, but there are 133 bridges spanning it. Compared to these rivers, it seems strange that there is not a single bridge over the Amazon River, whose basin is home to more than 30 million people.

Regarding the mystery of why no bridges have been built across the Amazon River, Walter Kaufmann , a professor of structural engineering at the Swiss Federal Institute of Technology Zurich, said in an email to Live Science that ``bridges across the Amazon River are not so urgently needed.'' No,” he points out. Most of the Amazon River meanders through sparsely populated areas, with few major roads connected by bridges, and boats and ferries are not established as a means of transportation in the cities and towns that border the river. Therefore, there is no need to rush to build a bridge.


Stephen Horvath

Kaufmann said technical and logistical challenges posed by the nature of the Amazon River also hinder construction of the bridge. For example, the Amazon River basin has extensive wetlands and soft soil, requiring very long viaducts and deep foundations. This means that building a bridge requires a large amount of financial investment, and even if a bridge is built, there are few benefits that justify the economic cost.

Additionally, the location of the Amazon River changes depending on the season, and there are significant differences in the water level. Especially in the lower reaches of the Amazon River, the average river width is about 3 to 10 km during the dry season from June to November, but it can be up to 50 km during the rainy season from December to April. Kaufmann said, ``The Amazon environment is certainly one of the harshest in the world.'' ``Construction of bridges across straits is difficult when the water is deep, but at least they can be constructed using pontoons (aquatic structures).'' is possible.”

At the time of writing, there is no bridge that crosses the main stream of the Amazon River, but a bridge called Ponte Rio Negro that crosses the tributary Negro River opened in 2011. In 2019, Brazilian President Jair Bolsonaro announced infrastructure projects including the construction of a 'bridge over the Amazon River,' and the city of Manacapul in the Brazilian state of Amazonas announced plans to build a bridge across the upper reaches of the Amazon River. There is a non-zero possibility that a bridge will be built across the Amazon River in the future.

However, American biologist Philip Fearnside , who spent a long career in Brazil, said, ``Construction costs would be prohibitive compared to the economic benefits that a bridge over the Amazon River would bring.'' `` Manaus Free Trade It is cheaper to transport products by water from factories in the region to São Paulo .” It also warns that plans to build a bridge across the Amazon River will give loggers easier access to the rainforest and lead to environmental damage.

'I think bridges will only be built when the need outweighs the hardship and cost,' Kaufmann said. 'Personally, unless there are unforeseen economic developments in the area, I think bridges will be built soon.' I don’t think it’s going to happen.”

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