New underwater tunnel in Santa Catarina promises crossing in 2 minutes at a depth of 29 meters; VIDEO

The tunnel uses the same technology used in the Santos-Guarujá project in São Paulo. In Europe, a similar structure is being built between Denmark and Germany, and will be the world's largest immersed tunnel.

In light of this new step, g1 Santa Catarina prepared a report to explain the details of the project, which promises a crossing of up to two minutes for cars between the two cities.

In this report, you will see:

1. What is the crossing like nowadays?
2. Why an underwater tunnel?
3. What will the tunnel be like?
4. How much will the tunnel cost? Who will pay?
5. When will construction begin? How long will it take for the tunnel to be completed?

The cities of Itajaí and Navegantes are separated by the Itajaí-Açu River , the most important in the region.

Currently, the connection between the two cities is made as follows:

• 🛣️across the bridge via the BR-101 highway;
• ⛴️by ferry , which can carry both vehicles and pedestrians.

Both modalities, however, have challenges, according to the Multipurpose Intermunicipal Consortium of the Association of Municipalities of the Itajaí River Mouth Region (CIM-Amfri), responsible for the project.

Architect Rafael Albuquerque, who works at CIM-Amfri, summarized the problems:

"Local traffic, commuting between cities, using the federal highway ends up adding to the usual traffic on this federal highway. Or it is at the mercy of long lines waiting to use the ferries. In terms of urban mobility, our region is on the brink of collapse."

The submerged tunnel was chosen taking into consideration other structures in the cities, such as Navegantes airport and the two ports , Itajaí and Portonave.

To build a bridge, for example, it could not be too high, so as not to interfere with planes, nor too low, so as to interfere with the passage of ships.

"The determining factor was the height required for a bridge connection. For the airport, the maximum permitted height is 45 meters, while to meet port demands, the minimum permitted height is 65 meters," explained Albuquerque.

The tunnel solution has been discussed for about eight years, according to the architect.

The tunnel's depth was designed to avoid hindering the river's shipping traffic, which supplies the ports of both cities. These vessels require a depth of 14 meters, so the structures were located deeper.

Check out the tunnel's features:

• 🚗 The tunnel will have two structures with three lanes in each direction. One lane in each direction will be dedicated to public transportation. Vehicles should cross in one to two minutes;
• 🚶‍♀️ Between the road structures, there will be a central lane for pedestrians and cyclists, equipped with moving walkways and also accessible by elevators;
• 📏 It will be about 500 meters long, 29 meters deep (equivalent to a nine-story building) and 36 meters wide;
• 💸 Drivers will pay a toll to cross the road, but the amount has not yet been determined. Pedestrians and cyclists will be exempt;
• ⚠️ The tunnel will not be transparent. The ramps will have a maximum incline of 5%, suitable for bicycles.

The final location of where the tunnel will begin in each city depends on geotechnical studies that will be commissioned in the next phase of the project, CIM-Amfri reported.

The tunnel's construction will be made possible through a public-private partnership. According to CIM-Amfri, the bidding process is expected to be launched 18 to 24 months after the contract with the World Bank is signed.

The winning company will be responsible for the construction, operation, and maintenance of the tunnel for a specified period. The estimated investment for the project is approximately US$180 million (approximately R$975 million), a figure that may be adjusted after the technical studies are completed.

The state government will provide financial assistance to the project, confirmed the Executive Secretariat for International Coordination and Strategic Projects.

Construction work is expected to begin in the second half of 2028 , if it is possible to sign the contract with the World Bank by October of this year.

The deadline for the work to be completed is 2032. The information is from CIM-Amfri.