Clay sewer pipes were used throughout history, up until pretty recently. Although you will still find some clay sewer pipe being installed in California, new clay pipes are not being put into the ground like they used to be. In the 1960s and 1970s, with the advent of plastic sewer pipes, clay started falling out of favor. Here’s what you need to know about clay pipes and their new alternatives.
The History of Clay Sewer Pipes
Vitrified clay pipes, also known as terracotta sewer pipes, were a common choice in ancient times. In the United States, they came to be used very early on and were still very popular until relatively recently.
Clay pipes started being phased out in the 1960s and 1970s when plastic sewer pipe options such as ABS and PVC were developed. It took until about the 1980s for clay pipes to stop being used in residential structures, so some buildings that were constructed around this time may still have clay sewer pipes or another kind of old pipe material.
In California, clay sewer pipes were not always preferred over wooden and cast-iron pipes. Wooden pipes made from redwood naturally resisted rot and fungus. It was also lighter and easier to transport than clay pipes. Wood also didn’t contract and expand like cast iron in changing temperatures. However, cast iron provides the durability and sanitation that we expect, and are therefore still in use today for sewage and septic systems. Although, they are not typically preferred over plastic pipes.
Clay pipes do offer one big advantage though: they have excellent tensile strength. Clay pipes can withstand high levels of downward force without cracking, which makes them a great choice for laying under roads. Old clay pipes can also last 50-60 years without needing to be replaced, which is why they became such a popular option in the first place.