Trenchless technology, which is also called “no-dig” technology is the science of installing, repairing and renewing underground cables, pipes, ducts other utilities with the use of techniques that eliminate the need for excavating the ground. And for this and other good reasons, it has been embraced by most companies that are into civil construction. Open-cut method, on the hand, is the use of open trench or excavation for the installation, repairing and the renewal of all underground utilities. Then the excavation is backfilled after the process. The technology, equipment and drill crews for trenchless are more sophisticated, and this has helped in its expansion, however, there is still a significant and growing market space for the open-cut method. And generally in civil construction work, certain factors should be considered in choosing between trenchless and open-cut methods. This article talks about the considerations for both methods.
Rural installation considerations
Rural areas are known for less activities compared with the urban areas. And since there is often fewer activities or obstacles and less restoration to contend with in rural areas, it better to go for open-cut method for trenching and plowing since this will be faster and more cost-effective when dealing with small diameter products. Although, open-cut method is not environmentally friendly as there will be substantive air and noise pollution to the various activities going on in that location, some civil construction companies are still using it.
Urban installation considerations
Urban areas are characterized with large traffic as different business activities are going on there apart from the fact that most ground surfaces are occupied with buildings. Considering all these it will be better to go for trenchless technology in such places. Also, in the highly populated areas and places with more developed infrastructures, it will make no economic sense to start digging or making excavation in such places. It is better to use the horizontal directional drilling (HDD) method for any work to be done there as it is more environmentally friendly compared with the open-cut method. With HDD, you are certain to cause less hindrances to the flow of traffic and other important activities going on at the ground surface. And in most cases, boring a utility line takes less time and more cost-effective in such locations since all you have to do is to go under sidewalks and road and not through it. Apart from that, you have avoided above-ground obstacles while doing your work. However, there are urban and suburban regions where open-cut is better, especially in some areas in Middle East, Africa and some parts of Europe, where unmarked underground utilities are a major issue. And when it comes to crossing under roads, bridges or installation covering a very long distance, trenchless is better.
Large-diameter pipe considerations
During pipe laying projects involving water, gas or oil, in most cases, both the trenchless and open-cut methods are used. When working over very long distances, open-cut will typically be more cost-effective, but contractors should also consider using the horizontal directional drill, auger boring machine or any other piercing tools to cross under rivers, roads or railways. And when it comes to installing large-diameter steel in short distances, or in places with limited space, auger boring machines are the better option.
Conclusively, in areas that are more wide-open, the contractors need to consider which method makes more sense economically considering the existing utilities, the soil type, the nature of the ground, the required depth and the size of product to be installed. For example, it may be less expensive to make use of the open-cut method for installations that are not deep or where the soil is not too hard. However, for deeper installations or those in rocky areas, it is better to go for the trenchless as less excavation would be done in such areas during installation process.