Water pipes form part of the utility infrastructure of modern society, providing us with clean water for most of our needs. In some cases, the water delivered is clean enough to for drinking, either straight from the tap, or with boiling or minimal filtering.
The invention of water pipes probably started when cities, complex agricultural water structures, and utility networks had to be made to supply large human settlements. As time passed, even though the materials and some of the construction for water pipes have grown in complexity, they maintain their basic use: water delivery.
Materials
Historically, one popular material for use in water pipes was lead, since it could easily be shaped and formed to fit any structure or network. In fact, the term “plumbing” itself is derived from the Latin word for lead, plumbum. It has been suspected that the high rate of stillbirths and infant mortality in early developing civilizations (and all the way to the Industrial Age) were affected by the use of lead-laden water, as lead poisoning had yet to be defined. The only way that the ancient Romans themselves were not totally affected was because of the high calcium levels in their water, which coated the pipes internally. Later on, hollowed-out wooden logs would be used in the 16th and 17th centuries, concurrent with the use of copper pipes. The introduction of cast iron and ductile iron lowered the cost of water pipe installation, though they had to be careful about electrochemical corrosion when different metals were used for a water delivery network.
Modern Times
To date, there are plastic materials that can replace most of the metals used in water pipes, such as the following:
PVC
Polyvinyl chloride pipes are one of the standards for plumbing now, due to its low cost, relative resistance to biological and chemical reactions, and its workability on-site. It is commonly used in situations where metal corrosion will be an issue. However, if the water going through it goes above a certain temperature, PVC will start to degrade. As such, it may not be a good idea for heating systems.
CPVC
Chlorinated polyvinyl chloride has many of the features of PVC, but has a higher temperature limit. It is easier to shape and bend, but requires specialized solvents to connect to other piping. It is also known to have fire-retardant properties.
PEX
Cross-linked polyethylene pipes may be more expensive than PVC or CPVC, but they do not require glue for fittings. In fact, crimping or using a special wrench seems to be enough. However, certain types of brass fittings seem to have a degrading effect on PEX pipes, and the material itself should not be exposed to sunlight.
Stainless Steel: For Drinking
For water pipes that are meant to bring in drinking water, many people prefer to use stainless steel pipes, as they have excellent corrosion resistance, and the leaching of elements into the water is within safe limits. Since they are easy to weld, and are more ductile than other metals, water leaks can be addressed easily, reducing wastage. They are also recyclable, so replacing them may have a reasonable return on the original cost.
