Santa Tereza-Voturuá Reservoir-Tunnel is located on the border between São Vicente and Santos Disclosure/Sabesp Did you know that the largest treated water reservoir in the form of a tunnel in Latin America is located between the cities of Santos and São Vicente, on the coast of São Paulo? With capacity to store 110 million liters, the structure was excavated in rock inside the Santa Terezinha and Voturuá hills. To g1, Sabesp informed that the Santa Tereza-Voturuá Reservoir-Tunnel serves Santos and São Vicente, in addition to reinforcing the supply of Guarujá and Praia Grande. Also according to the company, the structure is strategic for water security in Baixada Santista. ?Click here to follow the g1 Santos channel on WhatsApp. Construction began in 1979 and ended in 1981, being carried out simultaneously on the side of both cities. As previously disclosed by Sabesp, the tunnel was built 42 meters above the sea so that the supply would be by gravity, saving resources with electrical energy. According to the Santos Archive and Memory Foundation, the tunnel was excavated in granite gneiss rocks that are around 600 million years old, the same formation as Sugarloaf Mountain in Rio. The quality of the material made it possible to take advantage of the local structure itself. Santa Tereza/Voturuá Reservoir-Tunnel was inaugurated in 1981 Disclosure/Sabesp The reservoir is more than a kilometer long and is divided into two chambers, each around 13 meters high and 15 meters wide. Check below how much is equivalent to the maximum capacity of 110 million liters: ?220 million 500 ml water bottles; ?44 Olympic swimming pools with 2.5 million liters of water; ?55 thousand tanker trucks with a capacity of 2 thousand liters. Santa Tereza-Voturuá Reservoir-Tunnel is located on the border between São Vicente and Santos Collection A Tribuna g1 also gathered some interesting facts about the reservoir, according to information from the Santos Archive and Memory Foundation. See below: ?During the works to build the reservoir, the stones removed from the hills were used to form the Submarine Outfall; ?Studies have identified that the rock mass where the tunnel was inserted has a geological age of approximately 600 million years; ??The tunnel is made up of gneiss granite rocks, the same formation as Sugarloaf Mountain, in Rio de Janeiro (RJ). The quality of the material allowed the use of the local structure itself. Santa Tereza-Voturuá Reservoir-Tunnel is located on the border between São Vicente and Santos Collection A Tribuna Inside the tunnel Access to the tunnel is via the Voturuá Ecological Park, located on Rua Dona Anita Costa, in São Vicente. The reservoir has already been opened for public visitation a few times. In fact, the reporting team from TV Tribuna, a Globo affiliate, was on site in 2025 (watch below). The largest water reservoir in Latin America is located on the coast of SP. Despite this, Sabesp told g1 that the reservoir is not open to public visits. "Access to the interior of the structure only occurs during scheduled maintenance, when internal cleaning is carried out," explained the institution. The company added that a set of investments is underway aimed at strengthening water security in the region. The expectation is that Baixada Santista will receive another 21 reservoirs by 2029, increasing capacity to more than 130 million liters. "Together, they will have a volume that exceeds the storage capacity of the Santa Tereza-Voturuá Reservoir-Tunnel, reinforcing the system's infrastructure and ensuring greater operational security for supplying the population", he concluded. Entrance to the Santa Tereza-Voturuá Reservoir-Tunnel A Tribuna Collection VIDEOS: g1 in 1 minute Santos