Signs That Water Pipe Lining is Failing

Water, for all its benefits, is one of the earth’s most destructive forces. Given enough time, it can dissolve the planet’s hardest minerals, carve mammoth canyons, and shape mountain ranges. The infrastructure designed to transport it from source to tap is not immune to this significant power. In fact, if left unattended, it’s just a matter of time before the pipelines and mains we rely upon fail. With that said, there are some key indicators that allow maintenance personnel to identify impending pipeline failure.

Before delving into these indicators, it’s important to understand a pipeline’s first line of defense: epoxy liner.

Epoxy Liner: What Does it Do?

  • Some of the benefits associated with the application of an epoxy liner are:
  • Improved safety for drinking water over unlined or cement pipes.
  • Increased life span - the life expectancy of liner epoxy is roughly 100 years.
  • More cost effective compared to pipeline replacement.
  • Eliminates corrosion of the pipe, which weakens the pipe and affects flow.
  • Can be applied to any existing pipeline, fabricated from any material, above or below ground.
  • In addition to helping to prevent leaks and breaks, epoxy liner prevents heavy metals from leaching into the water.

Sign #1:  Epoxy Layer Application is Non-Uniform

Uneven adhesion can greatly reduce the effectiveness of a pipeline’s epoxy lining. If unevenly coated, the effectiveness of the epoxy is seriously degraded and pipeline corrosion will occur much more quickly then it would if the epoxy was properly applied.

This potential failure of the system can be identified by removing a segment of a straight length of pipe and visually inspecting the layer thickness at different points within the pipe.

Sign #2: Water Intrusion in Tee Sections

Tee sections of pipelines pose unique challenges to proper epoxy application. As such, spot checking these transition points can provide maintenance personnel with a glimpse of the condition of the epoxy liner at these crucial points. Since the standard application method used to apply the liner requires adequate preparation of the interior surface of the pipeline (typically involves sandblasting, to promote adhesion), and these transition points often connect components of different materials and thicknesses, a pipeline’s tee sections are especially vulnerable to liner failure.

If fittings are connected after the application of the epoxy liner it can result in a transition point that connects a protected to an unprotected segment, and uneven degradation of the material is inevitable.

Sign #3: Delamination of Epoxy Within the Pipeline

Simply put, delamination of the epoxy liner is attributable to a failure in proper adhesion. During delamination, the epoxy separates from the pipeline’s interior lining, which can result in significant maintenance issues. The separation of the liner allows the corrosion process to develop unhindered, which can further detach the lining and further reduce the effectiveness of the coating.  

As effective as it might be, epoxy liners are not infallible. However if they are applied properly and those responsible for maintaining the system know what to look for, significant integrity issues can be avoided. Hopefully this guide has at least succeeded in identifying some of the most common signs of epoxy liner degradation.

If you’re looking for more information on the various issues that can plague water pipelines, especially water leak detection services, consult the team of experts of Echologics.