The airflow now moves between the North and South beneath the Teno massif. After three and a half years of excavation, the Erjos tunnel, a crucial part of the Island Ring, witnessed the mechanical breakthrough of the final two meters of the wall separating the two galleries drilled from Santiago del Teide and El Tanque. This milestone marks the completion of the connection between the two sections, covering a distance of 4,855 meters.
The parallel tunnel, running alongside, has already reached 4,555 meters of drilling, accounting for 97% of its length. Only 300 meters remain to be completed, and it is expected to be finished by August, as per the forecasts of the Regional Ministry of Public Works, Transport, and Housing.
To expedite the excavation work, drilling has been carried out simultaneously at all four entrances, operating around the clock in three eight-hour shifts, seven days a week. Robotic excavators have been utilized, and drilling techniques have involved both blasting and mechanical methods, depending on the terrain conditions. This approach has allowed an average daily drilling rate of 15 meters.
Upon completion, the project will feature two cut-and-cover tunnels, with lengths of 140 meters at the south portal and 100 meters at the north portal. This expansion will increase the length of the largest tunnel in the Canary Islands, and one of the largest in Spain, to the projected 5.1 kilometers.
The breakthrough of the first tunnel, which closed the western section of the Island Ring, has confirmed the predictions made by the Director General of Road Infrastructure, José Luis Delgado, last October. At that time, with 60% of the drilling completed, Delgado had anticipated that the two north-south connections would be established during the summer.
Once vehicles begin circulating through the double tunnel, expected to take no less than 15 months, it will significantly alleviate traffic congestion on the TF-5 motorway and enhance economic connectivity between the north and south of the island. Moreover, travel will be safer and faster.
The dual carriageway is projected to accommodate approximately 17,000 vehicles daily crossing the Teno massif, a figure surpassing the initial estimate of 5,000 cars. Technical studies indicate that within a decade, the traffic volume is expected to exceed 30,000 vehicles. José Luis Delgado emphasized that this marks “the beginning of the end of traffic congestion,” and believes that this major infrastructure project will transform island mobility. As an example, he stated that someone living in Tacoronte who needs to travel to the south will save time by using the western route.
Motorists traveling between El Tanque and Santiago del Teide will save over 20 minutes compared to the current winding mountain road, TF-82. The new section of the dual carriageway, once completed and connected to the rest of the TF-5, spans 11.3 kilometers, with nearly half of it underground.
The groundbreaking ceremony was attended by numerous authorities and technical managers involved in the project. The Acting President of the Canary Islands Government, Ángel Víctor Torres, praised the four years of work, highlighting that 13 out of 16 road projects in the Tenerife road agreement are already in the construction or tendering phase, accompanied by environmental impact assessments.
Erjos Tunnel: a significant milestone for Tenerife
Pedro Martín, the Acting President of The Island Council, emphasized the focus of the institution on advancing road projects and executing works during his term, in collaboration with the Government of the Canary Islands. He described the underground infrastructure as a significant milestone for Tenerife.
Emilio Navarro, the Mayor of Santiago del Teide, hailed the project as not only economically significant but also socially, in terms of health and family reconciliation. Representatives from El Tanque, Los Silos, and Buenavista also attended the event.
The construction of the Erjos double tunnel, known for its challenging terrain conditions, was awarded in 2019 for 241 million euros. However, due to price adjustments, the budget has increased to 256 million euros. A portion of this amount, 18 million euros, has been allocated for environmental actions surrounding the project. The Canary Islands Government has already paid certifications totaling 120,334,038 euros, nearly 47% of the initial budget, under the Canary Islands-State road agreement (2018-2027).
Excavation work commenced on November 25, 2019, in the municipality of Santiago del Teide, carried out by the joint venture formed by Fomento Construcciones y Contratas (FCC), El Silbo, and Syocsa-Inarsa. The project directly employs 102 workers, including operatives and specialized personnel, and an additional 204 people, including suppliers, drivers, and catering staff attending to the workers.