Pipe Bursting is a lower cost alternative to traditional excavation and replacement. Many factors must be considered while weighing solutions. Factors which commonly impact construction are the size and difficulty of the project, the level of risk, and the market conditions for the job. Each project has unique factors contributing to the choice of pipe bursting. In general, pipe bursting is less expensive than traditional excavation and replacement when there is a relatively low density of service connections, surface areas are paved or otherwise improved, there are surface obstacles (e.g., water bodies, roadways, railways), or Environmentally sensitive areas like wetlands exist. Other factors include conflict with other utilities, contamination of soil, or the disruption of the site needs to be minimized.
Increases Flow Capacity:
One of the main features of pipe bursting is that flow capacity can be increased by installing a same size pipe or larger pipe. While this upsizing can be done with traditional pipe replacement, pipe bursting accomplishes this goal with less risk, at a lower cost, and in less time.
In addition to underground access conflicts, such as other existing utilities, access to the site from the surface can present challenges that increases costs when traditional excavation is being considered. Replacement of pipes under railways, roadways, or water bodies can increase cost to the project dramatically, not to mention delays resulting from permitting requirements and technical challenges. Utilizing pipe bursting to cross under these surface obstacles will reduce time and cost, and disruption to the public.
Reduced Trench Settlement:
Even the best excavation projects risk subsequent subsiding of the trench, resulting in pavement settlement. Many projects allow for pavement settlement over a period of time prior to final paving; however, this additional step in a project increases overall cost. Even if covered under warranty, additional return trips to make pavement repairs further increases the costs of disruption to the public.
As trenches settle, parallel or crossing utilities can also be negatively impacted as fill and surrounding soils shift with the settling trench. The resulting damage to other utilities may be recognized soon after trench settlement, or some time well into the future.
Avoidance of Hazardous Materials:
If soil surrounding the pipe is contaminated, bursting through the contaminated area avoids having to address issues associated with testing and disposal. When the contaminated area is very large, placement of access pits for pipe bursting significantly reduces the volume of contaminated soil that has to be disposed of.
Where Rehab isn’t the Solution:
Where rehabilitation is not the solution, the Owner/Engineer turns to replacement. And pipe bursting is often the solution. Here are a few examples:
- Where an existing pipe is severely “squatted” (i.e., excessive ovality), beyond the amount that can be addressed by cured-in-place pipe (CIPP)
- When there is uneven deterioration of concrete pipe where a “shelf” is created above the flow line of the pipe
Advantages of Pipe Bursting:
The bursting method of pipe replacement is safer, less expensive, quicker, and is less disruptive and risky than traditional replacement.