Santos-Guarujá tunnel auction is this friday; everything you need to know about Brazil's largest infrastructure project

The immersed tunnel will be 1.5 kilometers long, with 870 meters submerged under the Santos Port navigation channel (Alexsander Ferraz/AT)

Awaited since 1927, when the first project was announced, the immersed Santos-Guarujá tunnel marks a historic milestone. The future concessionaire responsible for the unprecedented dry connection project in Brazil will be revealed this Friday (5th). The auction is scheduled for 4 p.m. at the São Paulo Stock Exchange (B3), in the capital. A full house is expected, with government officials, businesspeople, and over 40 accredited journalists, all focused on the most anticipated infrastructure project in the country. Vice President Geraldo Alckmin (PSB), Governor Tarcísio de Freitas (Republicanos), Minister of Ports and Airports, Silvio Costa Filho, among other authorities, have confirmed their attendance.

Competing in the bidding process are the Spanish company Acciona, in partnership with Ballast Nedam, a Dutch company that is a global reference in immersed tunnel construction, and the Portuguese construction firm Mota-Engil, which has investment from the Chinese state-owned company China Communications Construction (CCCC), another major player in construction and engineering. Proposals were submitted on Monday, and the envelopes will be opened this Friday.

“One of the conditions for signing the contract is the presentation of qualified subcontracting. Mota-Engil and Acciona, although large international construction firms, do not have experience with immersed tunnels, which is why they have subcontracted. Mota-Engil subcontracted CCCC and Acciona subcontracted Ballast Nedam, precisely to meet the certification requirement”, explained the State Secretary for Partnerships and Investments, Rafael Benini, in an interview with A Tribuna.

The route between the cities can be completed in just two minutes by car; the project will also include a Light Rail Vehicle (VLT) branch (Disclosure)

“After the auction, there will be a period for appeals and contract awarding (formalization of the winner). We will analyze all the paperwork and expect, within 30 to 60 days, to have the contract awarded and officially declare the winner”, said Benini.

As Brazil's largest infrastructure project, and qualified under the Growth Acceleration Program (PAC), the tunnel will be built jointly by the State and the Federal Government, with an estimated investment of R\$ 6.8 billion. Of this, R\$ 5.14 billion will be funded equally by both governments, and R\$ 1.66 billion by the concessionaire.

The winner will be the bidder offering the highest discount on the maximum annual public compensation value, set at R\$ 438.4 million (reference date: March 2025). The sponsored concession contract, under a public-private partnership (PPP), will last for 32 years, extendable, with the asset returning to the Federal Government at the end of the term. The future concessionaire will be responsible for construction, operation, and maintenance of the project, and may earn tariff revenue of R\$ 2.34 billion starting from the sixth year of the concession.

The dry connection will run from the Macuco region in Santos to Vicente de Carvalho in Guarujá (Disclosure)

Public funding Benini explained that, under the delegation agreement, the State and Federal Government each have 60 days to deposit their share into the project account. If one party fails to provide the funds, the other has 90 days to cover the shortfall. “If the funding is not provided, the concessionaire has the right to a ‘way out’, meaning they can withdraw from the contract. By that stage in the process, we will be halfway through next year”, he said.

Minister Silvio Costa Filho recently stated that the Santos-Guarujá tunnel will be similar to the Fehmarnbelt Tunnel, which will connect Germany to Denmark — currently the largest infrastructure project underway in Europe. According to him, the same technology will be used in the Baixada Santista tunnel. In addition to reducing travel times and boosting port logistics, Costa Filho believes the tunnel reaffirms Brazil’s position as a leader in infrastructure engineering in Latin America.

TCU denies request to suspend auction The Federal Court of Accounts (TCU) rejected on Thursday (4th) a request from the Public Prosecutor’s Office at the Court (MPTCU) to suspend the tunnel auction. The decision was made by Minister Bruno Dantas, the rapporteur for the tunnel case at the Court.

On Tuesday, MPTCU had requested the suspension of the auction, alleging possible favoritism by the Brazilian Development Bank (BNDES) in providing financing to foreign groups involved in the bidding, to the detriment of Brazilian construction firms. The alleged financing restrictions would have prevented local companies from participating in the project.

Dantas ruled that the arguments presented did not meet the requirements for suspending the bidding. He also emphasized that obtaining financing is a market risk.

Although the suspension was denied, the TCU ordered its technical unit to continue monitoring BNDES’s actions in the case. This oversight will take place under a separate process already established to audit the planning and execution of the project.

Bid document inconsistencies On August 27, Dantas required adjustments to the delegation agreement following a meeting with representatives from the Federal Government, the State, and the Santos Port Authority (APS), in order to ensure legal security. The parties agreed to sign an addendum to the cooperation agreement, with no impact on the project timeline.

Revisions On June 13, in Santos, Governor Tarcísio de Freitas stated that the bid document had been revised, increasing the project cost by nearly R\$ 1 billion, based on feedback collected during the international roadshow held in Europe, which gathered global infrastructure operators.

From dry dock to tunnel opening After the auction, once all documentation is verified, public funding is deposited, and the contract is signed, the concessionaire will determine the location for building the dry dock where the tunnel’s concrete structures will be assembled. “There are available areas in Santos and Guarujá, such as Prainha. The concrete block construction phase should be completed by 2030, when the structure will be immersed 22 meters deep in the port channel. The tunnel’s top will sit at 21 meters, with an additional meter for safety”, explained Rafael Benini.

Tunnel access works in Santos and Guarujá are also expected to begin in 2030. “Once the immersion is completed — sealed and opened — the next phase will involve paving, installing tracks (for the VLT), and implementing systems. Our expectation is to open the tunnel in 2031”, projected the Secretary.

With a total length of 1.5 kilometers, including 870 meters under the estuary channel, the tunnel will feature three lanes in each direction — two for passenger cars, buses, and trucks, and one exclusive for the VLT — in addition to a pedestrian and bicycle gallery. The crossing will take just two minutes.

Currently, travel between Santos and Guarujá is by water and land. Ferries and small boats transport over 21,000 vehicles, 7,700 cyclists, and 7,600 pedestrians daily. The crossing takes an average of 18 minutes — not counting queues and delays — while the route via the Cônego Domenico Rangoni Highway can take up to an hour to cover 45 kilometers.