Much of the civil infrastructure in the United States is old — including many of our water, sewer and storm lines. Many have been around for over five decades, and that’s a problem. Corrosion is one of the most important issues facing underground infrastructure around the country, and a recent study conducted by NACE International concluded that each year, corrosion costs the wastewater and water industries $36 billion. Sewer cameras are often used to spot corroded lines, but by then, the damage is done.
Underground pipelines can experience many different types of corrosion, including the following:
Selective Leaching or Dealloying
When this occurs, one element is removed from an alloy, and this problem is particularly common with brass pipes. When they dealloy, zinc is removed, leaving behind a copper pipe that is far weaker than its original state.
Sewer inspection equipment often spots eroded pipes. This is the most common cause of corrosion in sewer infrastructure, caused by a liquid flow that wears away at the material. A push camera inspection system may spot gullies, grooves and a distinct flow pattern on the pipe. Not only is erosion the most common type of corrosion, but it can also causes failures the fastest.
Pitting is caused when small holes or divots form in the walls of a pipe. Often, they form close together and give the appearance of a rough sidewall. Even with sewer cameras, pitting can be tough to see because the divots are often covered by corrosion products and debris.
This occurs when two different metals meet and corrode upon immersion in a conductive or corrosive liquid. The less corrosion-resistant metal will start to degrade at a faster rate than normal.
Simple chemical tests can reveal the time of failure when caused by a uniform attack, when an electrochemical or chemical reaction leads to thinning of the pipe’s material.
These types of corrosion can affect all pipes, but some materials are more likely to corrode than others. According to Utah State University researchers, ductile iron and steel are most likely to fail due to corrosion. This is one of the most common pipe materials in sewer and water lines, making it clear that corrosion poses a serious risk to our nation’s underground infrastructure.
In addition to the economic costs of corrosion, safety and health also suffer. Materials can be leached into the water, causing issues like gastrointestinal problems, physical and mental delays and liver and kidney damage.
Learn More About our Sewer Cameras
Luckily, regular inspection can help spot corrosion so it can be stopped and repaired. Our team of experts is happy to connect you with the best sewer cameras for your needs. Contact us today to learn more.