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Trenchless water main replacement is a process that can be used to replace an existing water main without having to dig up the surrounding surface. This article will explain what trenchless water main replacement is, how it works, and when it is a better option than open-cut replacement. We’ll also look at the costs and advantages of using this trenchless replacement method.

What is trenchless water line replacement?

Trenchless water main replacement is a process by which an aging pipe is replaced without having to dig up the surrounding area.

Replacing a water main without excavating the ground is often called trenchless replacement. This process uses different methods, such as horizontal directional drilling (HDD) and pipe bursting, to create a new water main without destroying the surrounding surface. Trenchless replacement is often used in areas with limited space or when the old water main is buried very deep, making it difficult to access.

When trenchless replacement is not possible, open-cut replacement–in which the old pipe is removed and a new one installed in the same place–is required.

Who needs this? Who would find this useful?

Both cities and individuals can benefit from trenchless water main replacement. A city could use the process to save money and reduce inconvenience when they need to replace a water main that is underground or old, but in otherwise good condition. A homeowner can use it to avoid digging up their yard in order to switch out an aging pipe for a new one, which requires more time and effort than trenchless replacement methods.

How does it work?

In trenchless replacement, a new pipe is pushed through the old one with a reamer. The technique for this varies depending on the type of existing water main and soil conditions. In HDD, a machine bores horizontally underneath the ground from one point to another–in some cases achieving depths of more than 100 feet–until it reaches the desired location. There, a drill bit is used to make a small hole in the old water main, and a new pipe is inserted through that hole. The new pipe is then pulled back through the soil until it emerges at the other end of the borehole.

Pipe bursting is another trenchless replacement technique. During this process, a new pipe is pushed through the old one by applying pressure from the outside of the existing water main. A reamer is used to remove small sections of pipe as needed to create room for the new pipe as it passes through.

What Are The Costs?

Cost estimates for trenchless water main replacements vary depending on the project, but they are typically less expensive than traditional open-cut replacements. HDD is more expensive than pipe bursting, but it can be used in a wider variety of situations.

For a more detailed explanation of the cost to replace a water line with trenchless, please read our article: The Average Cost of Repairs for an Underground Water Line in Atlanta, Ga

What are the advantages of using trenchless?

The advantages of trenchless water main replacement include less environmental impact, reduced noise levels, and quicker completion times. In addition, this process preserves existing infrastructure and is often better suited than open-cut replacement for older, shallow water mains that can be easily damaged.

What are the disadvantages?

Trenchless replacement may not always be an option for a municipality or homeowner because of the method used to access the old water main. In some cases, a water main in good condition may still need to be replaced because it is in a place where open-cut replacement is the only method possible.


Trenchless water main replacement can be a great alternative to open-cut replacement when an old pipe must be replaced because it is in an area where digging up the surrounding surface would not otherwise be possible.

Trenchless water main replacement can also be less expensive than open-cut replacement because it is more environmentally friendly and quicker.

The downside of trenchless water main replacement is that it might not always be possible to use this method of replacing an aging water main. It may also only be suitable for older pipes made out of cast iron and clay, and not PVC or other new materials.

In such cases, it’s important to seek professional plumbers experienced in both traditional and trenchless methods to determine the best approach for the specific situation.

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