Solutions For Lateral Rehab

By Jeff Griffin, Senior Editor | October 2010 Vol. 65 No. 10

The position of service providers, that property owners are responsible for lateral repairs, continues to impede progress on solving lateral issues. However, there are progressive system owners who recognize it is to their benefit to take responsibility for laterals in their systems.

Regardless of who ultimately is responsible, there are three basic methods for replacing or rehabilitating sewer laterals:
• Open-cut construction;
• CIPP (cured-in-place pipe) lining; and
• Pipebursting.

Open-cut construction
For years, the only way to install new sewer laterals or repair/replace old pipe was to dig a trench and put in pipe or make necessary repairs, and fill in the excavation. It’s a simple, straightforward process that all contractors have the equipment and knowhow to do. However, excavation damages lawns and if the lateral pipe is buried under drives, walks or patios the job becomes more complicated. If excavations are not properly compacted, fill can settle, causing continuing problems.

CIPP rehabilitation
Rehabilitating a lateral with CIPP lining involves inserting an inverted felt tube liner saturated with epoxy-based resin into the lateral where it is cured by heat to form a new “pipe” within the old pipe.

CIPP lateral rehabilitation causes the least surface disturbance of any rehabilitation/repair method available.

CIPP can be successfully employed on most lateral projects, said Gil Carroll, director of business development at Applied Felts, a pioneer in the CIPP process and manufacturer of MaxLiner systems.

“Given that most laterals are within four to six inches in diameter and go directly to property line clean-outs where lengths are typically no more than 40 feet,” said Carroll, “there are really no special circumstances that limit the use of CIPP for lateral rehabilitation and repair. CIPP can be used for every standard and non-standard length required by a lateral.”

Carroll said one point of access is needed -- either from the clean out on the property or the main line if a seal also is being produced. In most cases, it is possible to shoot a blind shot from one point to the other without limitation.

Most laterals needing attention exhibit a variety of problems, including broken pipe and root intrusions which are identified by inspection prior to the lining process.

To line a lateral, the pipe must be clean and clear of blockages, and the first step is a careful CCTV inspection.