The overwhelming majority of tunnels constructed around the world are completed to an extremely high standard with the expectation that they are going to last decades.
There are a lot of reasons for this, including advanced technology, efficient use of conveyor belts to aid in construction and years of intense planning in order to be prepared for every eventuality and deliver within cost, quality and time standards.
A lot of the successful tunnels we have seen have worked due to the simple principle of measuring twice and cutting once; in other words, the planning and preparation made the execution stage far simpler and far less prone to unexpected curveballs.
Not every tunnel is created with this logic, however, but the ones that were not made with this level of forethought do at least provide some useful lessons for how to get it right next time.
The Path Of Least Resistance Is Not Always The Best Path
In the 1970s, the people of Guoliang Village in China had a problem. The village was largely isolated from the outside world, only accessible by an infamously treacherous stairway known as the Sky Ladder.
To make it easier for the villagers to reach the outside world, a team of 13 people sold their livestock to buy hammers, chisels and other manual tools to carve a road into the side of the mountain.
It took five years in total to dig out the 0.78-mile tunnel with just a single lane of traffic, something that is nothing short of a miracle.
With that point made, the tunnel itself is fraught with issues owing to the necessity of taking the path of least resistance. It is steep, uneven, has no barriers, no light outside of a few holes carved out into the mountainside, and an infamous number of twists and turns.
This was a necessity due to the manual construction, but it has become known as “the road that does not tolerate mistakes” as a result.
Build Based On Environmental Conditions
Plenty of tunnels are built under sea level, even if they are not necessarily designed to be underwater or undersea tunnels.
For the most part, this is fine, but the design of the tunnel needs to be mindful of the environment it is built around. It ideally should be completely free of leaks, and if it is not, it should be designed in such a way that any water that does enter does not render the tunnel a death trap.
This is not the case for the Lefortovo Tunnel in Moscow, better known as The Tunnel of Death due to the nature of its design causing treacherous conditions for drivers, leading to frequent loss of traction, sliding and crashes.
The reason for this is a combination of problems with the execution of the tunnel leading to leaks from the Yauza River and extremely cold winter temperatures in the tunnel itself, causing the standing water to freeze and turn the road into an ice rink.
Whilst the tunnel was not the first plan for the road project, once it became clear that only a tunnel could be constructed, the first priority should have been to make sure that this exact scenario could not occur.
Practical Standards Are Always More Important Than Aesthetics
In tunnel design, there always need to be contingencies in place to protect people’s lives and ensure the safe running of the tunnel. After all, a tunnel that is closed due to an accident or safety concerns is less than useless compared to one designed to ensure a safe evacuation.
These design considerations are far more important than aesthetics, particularly aesthetics that do nothing but make the tunnel more dangerous and mask the failure to deliver even close to what was promised and seriously injure workers in the process.
This was the case with the Vegas Loop, a tiny network of tunnels underneath Las Vegas which use chauffeured electric vehicles to drive people around and have been described as a “death trap” due to the lack of emergency exits or the ability for emergency services to reach the scene of an accident.
The initial plan of a hyper-speed electric pod on semi-guided rails was replaced with RGB glowing lights, conventional chauffeured electric cars and a top speed closer to 35 miles per hour, although in some congested periods, it was apparently closer to four miles per hour.
The system was not designed terribly well, disguising its failings in the veneer of futurism.
