What is one advantage of using vitrified clay pipe (VCP) for gravity sanitary sewers?

One advantage of using vitrified clay pipe (VCP) for gravity sanitary sewers is its high resistance to chemical corrosion. VCP is made from natural clays that are fired at high temperatures, resulting in a dense, non-porous material that can withstand harsh chemicals commonly found in wastewater. This property makes VCP particularly suitable for sanitary sewer applications where prolonged exposure to various chemicals can lead to degradation in other pipe materials.

In addition to its chemical resistance, VCP is also known for its durability and long service life, often exceeding 100 years with proper installation and maintenance. This longevity can offset initial installation costs over time, providing an economical solution in the long run.

The other options highlight attributes that are not characteristic of VCP, such as high flexibility (which is more relevant to other materials like plastic pipes), low expansion rates (though VCP does have minimal thermal expansion, it is not as flexible as plastic), and low costs relative to metal pipes, where VCP tends to be more advantageous in terms of durability rather than upfront costs. Overall, the high resistance to chemical corrosion stands out as a definitive advantage for VCP in the context of gravity sanitary sewers.