Pipe Bursting

Pipe bursting, also called in-line expansion, is a proven and affordable form of trenchless pipeline rehabilitation, especially where maintaining capacity is critical. In fact, it’s actually pipeline replacement, using the existing pipe as a conduit for the new one.

Service Overview

EWSG pipe bursting crews have decades of experience using this relatively low-tech, high-value-return method. Pipe bursting typically yields the largest increase in hydraulic capacity of any other trenchless rehabilitation method. This is because other methods—such as lining the inside of the pipe—decrease the existing pipe’s inside diameter and capacity. For this reason, pipe bursting might be especially effective in projects that require maintaining or increasing the size of the current pipe, as well as replacing defective segments. Used in the U.S. since 1986, pipe bursting now rehabilitates more than a million linear feet of pipe per year.

Problem

Stormwater and sewer pipes can deteriorate and fail in any location, regardless of accessibility to make a repair. Often these failed pipes lay in difficult-to-reach areas, or beneath busy roadways or city streets. In such situations, traditional dig-and-replace methods are simply too expensive and disruptive. They tear up streets for months at a time, create lots of dust, noise and hassle for drivers, and displace traffic to retailers, not to mention the expense of traffic re-routing and signaling.

Solution

Pipe bursting opens the existing pipe and forces it outward, then pulls a new pipe into the tunnel just created. This all happens underground the length of the pipe, with surface work happening only at both ends. Pipe bursting is a particularly effective choice for situations where the original pipe is significantly deteriorated and wouldn’t form a sound structure to reline; in sensitive natural areas where wildlife and flora must be protected;

in runs where there are so many defects that even trenchless methods would be too tedious; and in high-activity locations such as golf courses and amusement parks. It’s also a good option for residential and business service laterals, as it entails minimal surface disruption of yards and parking lots.

Result

The old, failed pipe is relatively quickly replaced with a functional new one that may allow for greater capacity, all at an affordable cost and with minimal surface disruption.

Tools and Methods

Our crews locate 5’ x 20’ pits at both ends of the run of pipe to be replaced, typically 4” to 80” in diameter, and of any commonly used material. They work primarily from one of those ends, setting up the expansion head and any needed cables there. The existing pipe is forced open using a bursting tool. Its hydraulic or pneumatic expansion head is pulled through the existing pipeline, typically using a cable and winch. As this happens, it pushes that pipe outward from the center until it breaks apart, creating space for the new pipe. The bursting device also pulls the new HDPE pipeline behind it, immediately filling the void created by the old, burst pipe. The new pipe may be of the same size, but from a practical and value-engineering standpoint, it’s often advisable to replace the existing pipe with at least the next larger diameter size (though it’s possible to nearly double the size if necessary). This approach allows some additional pipe capacity, in the case of increased loading conditions over time.