There are many telling signs of a pipeline in need of repair, from sewage puddles to unpleasant odors in the air. Once your pipeline has reached this point, it’s time to call in pipelining professionals and let them rehabilitate your pipe.
The expert team at SEKISUI SPR is a top choice for a seamless trenchless sewer repair. But what type of repair does your pipeline need? And are there pros and cons to each trenchless repair method? We’ll answer these questions and more below. Read on to learn the trenchless sewer repair pros and cons.
What Is Trenchless Sewer Repair?
Trenchless sewer repair, or trenchless pipe rehabilitation, is an increasingly popular method of repairing damaged pipelines. This repair method uses innovative technology to rehabilitate pipelines without needing to dig the above ground. Instead, trenchless lining technologies renew the pipe directly underground, lessening the impact on the environment. Additionally, since the trenchless repair method is able to be completed without digging or total pipe replacement, it’s a much more cost-effective method.
The Pros and Cons of Each Sewer Repair Method
Now that we’ve discussed what trenchless sewer repair is, let’s look at the different methods of completing this repair. We’ll dive into the trenchless sewer repair pros and cons of each below.
Spiral Wound Lining
Spiral Wound Lining is a SEKISUI SPR specialty. This trenchless sewer repair method involves the mechanical process of installing a wound PVC liner into the pipeline. This advantageous option minimizes the need for a temporary bypass and reduces the environmental impact of rehabilitation. Advantages and disadvantages of this pipeline repair option include:
- Environmentally friendly. Spiral Wound is 100% mechanical using no chemicals or thermal processes.
- Cost-effective. With a limited need for digging or total pipe replacement, this trenchless sewer repair method is often cheaper.
- Live flow lining. This method can be done in a live pipeline, minimizing the need for a bypass.
- Flexible. SEKISUI SPR’s Spiral Wound Lining technology can handle a variety of pipeline shapes and sizes.
- Cross-sectional loss. The wound PVC profile slightly reduces the ID of the host pipe, however, the hydraulic capacity of PVC (Manning’s Coefficient of .009) typically makes up for this loss.
- Gravity only. Spiral Wound liners are rated up to 10.7 PSI, meaning they predominantly serve gravity sewer, storm water, and culvert applications.
Cured-in-Place Pipe Lining (CIPP)
The next method on our trenchless sewer repair pros and cons list is Cured-In-Place Pipe Lining (CIPP). This method consists of inserting and curing a resin impregnated tube within an existing pipeline. The new pipeline is intended to act as a support to the existing pipeline, effectively repairing the host pipeline. This epoxy pipelining process does have a few pros and cons, such as those mentioned below:
- Minimal ID loss. The repaired CIPP liner offers very minimal cross-sectional loss.
- Variations. CIPP is offered in a number of forms that vary from the types of resin used (vynelster, epoxy, etc.) to the installation/curing method (heat, steam, tower, UV).
- Gravity + Sewer. The CIPP technology is offered for both gravity pipelines and pressure applications; such as pressure sewer or water mains.
- Permanence. Epoxy is a permanent and solid material that can be difficult to adjust. Once a CIPP repair has been completed, it may be challenging to repair the pipeline again later.
- Managing flow. CIPP requires a dry pipe for renewal which involves plugging and often temporary bypass pumping. This can add 15%-20% to the total cost of the project. However, the price of this repair option is still significantly less than taking the traditional open-cut repair route.
Pipe-bursting is a unique sewer repair method that safely replaces the existing pipe with a new one. In this process, a bursting head is used to break up the existing pipe while pulling a new pipe into the void that is left. Let’s take a look at a few of the trenchless sewer repair pros and cons of this method:
- Pipe upsizing. With this method it is possible to increase the diameter of the pipeline that is being replaced.
- New pipe. With the old pipe being destroyed, a completely new pipeline will act in its place.
- Pipe Condition. The existing pipe’s condition or level of cleaning is of smaller importance since it will be completely replaced in the bursting process.
- Excavation pits. Pipe bursting requires pits at both ends for a proper installation. Although pipe bursting is trenchless, it requires a bit of digging and backfill.
- Managing flow. With the existing line being taken out of service, the flow needs to be pumped around the area of repair.
Sliplining involves inserting a smaller pipe into the host pipe as a way to renew the existing pipeline. However, this process does require grout to connect the pipes and fill the empty space in between. There are quite a few advantages to this method, including:
- New pipe. The pipe inserted within the existing line is a new, typically HDPE pipeline.
- Live flow lining. With the installation process not requiring a dry pipe, sliplining can be conducted within live flow.
- Cross-section loss. If grouted incorrectly, this method can cause damage to the slip liner and require another repair.
- Cleaning. Since a new pipe is being inserted, the existing line must be thoroughly cleaned and cleared of any debris.
Spay-in-Place-Pipe Lining (SIPP)
SIPP involves spraying the interior of a pipeline the entire length with material in order to renew the system. The sprayed material is typically cement, polymer or an epoxy. The installation process uses machinery/robotics to coat the entire pipeline. This process has a number of pros and cons, including:
- Minimal ID loss. The internal coating marginally reduces the diameter of the pipe.
- Variety of applications. SIPP is capable of being used on gravity and pressure lines as well as round and non-round shapes.
- Managing flow. The SIPP process requires flow to be diverted around the area of repair.
- Cleaning. Since the original pipe wall is to be coated, a heavy cleaning is needed to clear debris and ensure a successful lining.
Evaluate each method depending on your project
While this list of trenchless sewer repair pros and cons can offer a clearer picture of what type of repairs are available, the best solution is dependent on the scope of work for your rehabilitation project. A project requiring bypass pumping for certain methods may not for others. A lining job in the city may have different above-ground restrictions than in the suburbs.
Contact our team to learn more about these different trenchless sewer repair processes and how we can help you rehabilitate your pipelines!