When pipes first had to be put underground, people did the obvious and easiest thing: they dug a hole, and put a pipe in it. But in the 21st century, the surface is full of important infrastructure like roads and buildings, and even the underground is increasingly jammed with buried utilities and other obstructions. In the world of tunneling, the word “trenchless” refers to a tunneling method that does not require the surface to be disrupted, in contrast with the simpler method of just digging a trench. Trenchless tunneling technology has been a game changer for utilities, allowing them to be installed quickly and cheaply, even in complex urban environments.
The history of trenchless tunneling technology goes back to the early 19th century, when the first attempts were made to install underground pipes without the need for surface excavation. It wasn't until the latter half of the 20th century, however, that the technology really began to take off, thanks to a few key innovations.
One of the earliest known uses of trenchless technology occurred in 1845, when a Scottish engineer named James Gordon was tasked with installing a water main beneath the streets of London. Rather than digging a trench from the surface, Gordon innovated a technique called "pipe jacking" to install the pipe. This involved digging a narrow shaft at one end of the pipe's intended route, and then forcefully pushing the pipe through the ground—using hydraulic jacks—to a similar shaft at the other end of the route.
Pipe jacking proved to be a relatively effective method for installing underground pipes, but it was slow and labor-intensive. In the decades that followed, a number of other trenchless methods were developed, including the use of horizontal drilling, which allowed engineers to create longer underground tunnels without the need for surface excavation.
One of the key developments in the history of trenchless technology came in the 1970s, with the advent of "directional drilling." This technique, which was first used in the oil and gas industry, involves the use of specialized equipment to create underground tunnels in a controlled and precise manner, making pipe installation and other underground infrastructure more accurate and efficient than ever before.
The 1980s saw the emergence of a number of other important trenchless technologies, including "pipe bursting" and "pipe relining." Pipe bursting involves breaking up an existing underground pipe and replacing it with a new one, while pipe relining involves inserting a new pipe into an existing one. Both of these techniques are faster and less disruptive than digging up an existing line or installing pipe.
The 1990s and 2000s saw the continued growth and refinement of trenchless technology. One of the key innovations during this time was the use of GPS technology to improve the accuracy of horizontal drilling, allowing for underground tunnels that were more precise and ensuring that the tunnels were aligned properly and that the pipes and other infrastructure were installed in the correct location.
The past few decades have also seen the development of new materials and coatings for underground pipes. These advances allowed for the creation of more durable and long-lasting pipes, which were better able to withstand the challenges of underground installation and the harsh conditions of the underground environment. The increased use and refinement of drilling fluids have also added to the distance and speed possible in trenchless tunneling, and drilling fluids are increasingly recycled to minimize environmental impact.
Today, trenchless technology is widely used around the world for the installation of a wide range of underground infrastructure, including water and sewage pipes, electrical and telecommunications cables, and natural gas lines. It is a faster, more efficient, and far less disruptive method than traditional excavation or trenching, and has revolutionized the way that underground infrastructure is installed.
