The Subfluvial Tunnel formerly known Hernandarias Tunnel was the first of its kind in South America and is a 7,864-foot pipe under the mighty Paraná, a river longer than the Mississippi and with the highest flow rate. This tunnel was opened on December 13, 1969.
The tunnel connects Santa Fé and Paraná, the two capitals of the Argentine provinces. A journey that used to take hours is now made easy and comfortable in minutes.
Another benefit that many talk about is the increase in tourism that the tunnel has encouraged. On both rivers, hotels, inns and bed and breakfasts are operating like never before. Brazil, Paraguay and Uruguay have bus lines that run through the tunnel, from there to tourist spots in Argentina. In October 1970, 70,654 cars and buses passed through the tunnel.
It's common to hear people ask, "Have you ever seen the tunnel?" It was this interest that piqued my curiosity. So when I visited a friend in Santa Fe, I expected to travel through the huge submarine tube.
In a few minutes we will arrive at the tolls. Cars have to pay 75 cents. Signs say the top speed is 60 kilometers per hour (37 miles per hour) and the lowest is 40 kilometers per hour (25 miles per hour).
In short, we are on the ramp of almost 300 meters leading to the tunnel. Around the last third of this ramp is a visual adjustment area. Here, the waning light allows our eyes to adapt.
Inside the tunnel, the air is cool and pleasant compared to the heat outside. The two-story concrete ramp is spacious, nearly 25 feet wide, and the roof nearly fifteen meters high. The side walls are covered with green tiles. I am very impressed with the width, lightness and purity of the tunnel.
Along the left wall there is a platform every one hundred and ten meters. In each of them we see a telephone, a fire extinguisher and a hose. On the same side there is a walkway protected by a balustrade for the guards.
We were soon in the visual alignment area across the river. The tunnel journey took about three minutes. But instead of satisfying my curiosity, it only increased. I decide to go home.
Later, during a tourist visit, I learn that the ventilation system allows a complete renewal of the air inside the tunnel every three or four minutes. In addition, two gas analyzers indicate the accumulation of carbon monoxide along the tunnel.
I also found that in the control room, fourteen televisions follow the trend of motor vehicles. In the event of an emergency, drivers will be instructed by a loudspeaker network installed approximately every four meters along the tunnel.
It is also explained that the simple act of lifting one of the phones puts a person in contact with the control room. In the event of a fire, we are informed that the 24 fire extinguishers and hoses are ready for use. For safety reasons, fuel tanks are prohibited from using the tunnel. They should continue to use the old ferry to cross the river.
I am particularly interested in learning more about the construction. Thirty-six giant cylindrical tubes, each about 215 feet long and thirty-five feet in diameter, and an adapter tube make up the entire tunnel. On the outside, three layers of polyester resin reinforced with glass wool make the pipes waterproof.
These pipes were prepared in groups of four, placed in a floating position and then lowered into a ditch that had been dredged to the bottom of the river. The frogmen came out and tied the pipes with iron bands. When the thirty-seven pipes were attached, they formed an airtight unit nearly a mile and a half long. Mud covered this pipe and the riverbed was as before.
The Argentine Underwater Tunnel is a true technical marvel.
Beautiful,nice one