Why Replace Conventional Trenching with Trenchless Technology?

By Denise Sullivan
Published: December 28, 2017 | Last updated: July 5, 2023
Key Takeaways

Trenchless rehabilitation is cheaper, less disruptive and requires less time to complete as opposed to conventional trenching projects, costing $50-$250 per foot.

Plumbing repairs are costly, and in most cases, they are not fully covered by homeowners’ insurance. Some plumbers still tell homeowners that they need to dig up pipes for repairs. While that may be true in some instances, such as collapsed lines, for the most part, trenchless solutions may be a better option.

The Problem with Conventional Trenching

Conventional trenching methods, sometimes called open-trenching, is when a crew digs away from the dirt, concrete or asphalt above the section of broken pipe, exposing it. Once unearthed, the team then removes the old plumbing and replaces it with a new line. Because the tubes must be wholly exposed to do the work, the costs and amount of time to complete the job add up.

The Cost Estimate of Conventional Trenching

An open-trenching project costs approximately $50 to $250 per foot. For a small, easily accessible job, the digging and replacement of the line costs between $3,000 and $6,000. However, if the repair project is more than 50-feet, homeowners can be looking at $5,000 to $13,000 for just the digging and new pipe.

The cost estimate is only for digging up the old line and installing a new pipe. It does not include any extra considerations. Re-landscaping, road closures and labor costs add to the bill. If the owner must tear up concrete from a sidewalk or driveway or asphalt from the road to complete the repairs, the price grows even more. In the end, the total estimated cost my reach over $25,000.

The Disruption of Conventional Trenching

Even if cost is not a factor, conventional trenching methods are disruptive. The workers must dig a trench in the area surrounding the line. This open space may pose safety risks to children and animals. When the repairs go into the street, lane or throughways close, disrupting traffic flow and causing problems for others. If the problem is under a home’s foundation, the dwelling may be unlivable during the repair time, costing residents more money for hotels and kennel fees.

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The Time Delays of Conventional Trenching

Conventional trenching methods are time-consuming. Water lines are buried deep beneath the frost line to keep the extreme weather from causing problems. With that in mind, digging soil to access these lines can take a full day, or more depending on how much line needs exposure. During winter months, this may mean digging through permafrost, which extends the job.

If the pipe lies under a foundation, it could take weeks to fully excavate the line, as workers must break through the concrete before digging through the soil. If the foundation is disturbed, workers pour new concrete, which must cure before the area is livable again.

Extra Equipment Needed During Conventional Trenching

Depending on the project, homeowners might have a significant crew on-hand during the repairs. Open-trench projects require at least one backhoe. However, a saw or jackhammer may be necessary for breaking up concrete and asphalt. A dumpster for disposing of concrete, asphalt and old pipe is also necessary. Large trucks and wenches to move pipe around may also be part of the project.

The Benefits of Trenchless Construction and Repair

Trenchless technology allows owners to repair their plumbing issues in a simpler fashion. For homeowners, the repairs may not be trenchless, as workers still need to access the line. However, the digging is minimal in comparison to the open-trench method. Technicians dig an entry point to access the plumbing. Most projects also require an exit or reception trench as well. Like the entry access point, the exit area is relatively small in comparison.

The Costs of Trenchless Repair

When compared to the overall cost of a trenchless project, homeowners find that it is cheaper. Projects run between $50 to $250 per foot, with an average project cost of $6,000 to $12,000. However, unlike with a traditional repair, there is no added cost of re-landscaping or repaving.

Less Disruption During Trenchless Projects

There is little disruption with a trenchless project. There is no diversion of traffic, even if the line goes under a street. Flooring is not disturbed, and residents do not have to leave during the repairs.

Short Timespan of a Trenchless Project

Overall time on a project reduction is from a few weeks to a couple of days. A team of three to four plumbers finishes within two to three days with plumbing repairs to an average house consisting of one kitchen, one laundry area, and 2.5 bathrooms.

The time frame includes a half-to-full day of preparation, a day to complete the project, and a day for inspections. A small backhoe may be necessary to speed up digging. However, the equipment needed for these projects is much less invasive.

At the end of the project, it takes less time to repair the damage. Since only soil is disturbed, workers return the excavated dirt to the hole. For the most part, seeding, sodding or re-landscaping is not necessary as the area is small.

What the Future Holds for Trenchless Tech

Relative to traditional plumbing repair techniques, trenchless technology is relatively new, with development in the last 40-years or so. While it has grown in popularity in The UK and America, many countries are still adopting the technology to put it to use.

In India, the city of Hyderabad is beginning to implement trenchless rehabilitation of their underground lines. In total, the city plans on using cured-in-place pipe to rehabilitate 120km of pipeline running under their feet.

In addition to India cities adopting the technology, areas of South America are beginning to take usage of these techniques. While parts of South America had already embraced the change to trenchless methods in the 1990s, smaller countries within the continent have not been as eager. These countries are beginning to change the way they repair plumbing.

Adoption in more countries is not the only future for trenchless projects. With the advancement of technology, better methods are emerging. Ground penetrating radar assists workers in locating leaks or cracks in underground pipes. (Learn more in "The View Underground: Ground Penetrating Radar.")

Robot technology allows workers to see inside the hazardous lines without risk to themselves.

Trenchless installation of environmentally friendly potable water mains is coming to many areas. EPA regulations make it necessary to renovate clean water mains in a way that will cause less contamination to the surrounding areas. Using pipe bursting methods, workers can install the new lines while removing the old ones without having to unearth them.

Trenchless technology has revolutionized plumbing repairs. With less downtime and overall cheaper cost to the consumer, it is the ideal method when it comes time to fix a pipe issue. As technology advances, the trenchless method becomes more advanced and a better choice.

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Written by Denise Sullivan | Technical Writer @ Trenchlesspedia

Denise Sullivan

Denise Sullivan is an accomplished freelance writer from Louisiana, with a Associate's Degree in Journalism from Eastern Oklahoma State College. She also graduated from East Central University with a Bachelor's in Biology. Denise began her writing career writing operations and maintenance manuals and software utility manuals for flight simulators. Since, she has expanded her writing to a broad spectrum of topics.

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