One way that I know that there is a lot of fiber construction occurring is that many of the people I talk to tell me that they’ve seen fiber construction in their neighborhood. I always ask about the type of construction they are seeing, and many folks can’t define it. I thought today I’d talk briefly about the primary methods of fiber construction.
Aerial Fiber. The aerial fiber construction process starts with steps most folks don’t recognize as being fiber-related. Technicians will use cherry pickers or climb poles for make-ready work that prepares the poles to accept new fiber. There might even be some poles replaced, but most people wouldn’t associate that with fiber construction. The construction process of hanging the fiber can be hard to distinguish from the process of adding wires for other utilities. There are generally some cherry pickers and a vehicle involved that holds a reel of fiber wire. The aerial construction process can move quickly after the poles have been properly prepared, and many folks won’t even realize that fiber has been added along their street.
Trenching. Trenching fiber is the best-named construction method because it exactly describes the construction process. With trenching, a construction crew will open a ditch with a backhoe and lay conduit or fiber into the open hole. Trenching is usually chosen in two circumstances. First, it is often the least expensive way to bury conduit along stretches of a road that don’t have impediments like driveways. When a contractor builds fiber in a whole city, trenching might be used along streets that have not yet been developed and that don’t yet have sidewalks. Trenching is usually the preferred construction method when putting fiber into a new subdivision – the ditches are excavated, and conduit is placed before the streets are paved.
Plowing. Cable plowing is a construction method that uses a heavy vehicle called a cable plow to directly bury fiber into the ground as the plow drives along the right-of-way. Fiber plowing is done almost exclusively when burying fiber cable along a route where the fiber will be placed in unpaved rights-of-way, such as along a country road. The right-of-way must be open and not wooded to allow access to the cable plow.
A cable plow is an unmistakable piece of equipment. It’s a bulldozer-sized vehicle that holds a large spool of fiber. It’s unmistakable to see a cable plow because folks will inevitably wonder what the contraption is moving along a country road. But the plowing work can proceed quickly, and the more noticeable crews are the ones boring underneath driveways and intersections along the plowing construction route.
Boring. Also called horizontal boring, trenchless digging, or directional drilling, this is a construction method that uses drills to push or pull rods horizontally underground to create a temporary hole large enough to accommodate a conduit. This is the technique used to place fiber under paved streets, driveways, and sidewalks.
Boring rigs come in a variety of sizes based on the length of the expected drill path. Small boring rigs might be mounted on the back of a truck. Large boring rigs are standalone heavy equipment that are often mounted on treads (like a tank) instead of wheels to accommodate a wide variety of terrain. It’s fairly easy to identify a fiber boring operation because there will be vehicles of all sorts around the area and usually large reels of brightly colored conduit nearby. The chances are that if you see fiber construction in a town, it is using boring.
Microtrenching. This construction process is unmistakable. A heavy piece of equipment that contains a giant saw cuts a narrow trench in the street. The saw is usually followed by trucks that haul away the removed street materials. The cutting process is loud and draws everybody’s attention. Microtrenching can be finished in a day in ideal circumstances where the hole is cut, side connections are made with a high-pressure water drill to get fiber under the streets and sidewalks, and the narrow trench is refilled and capped.