What type of water pipe is typically used in underground applications?

High-Density Polyethylene (HDPE) is commonly used in underground applications due to its exceptional resistance to corrosion and chemical damage. In environments where pipes are buried underground, they are often subject to various soil conditions and moisture levels that can lead to the deterioration of other materials. HDPE is known for its durability and flexibility, making it ideal for installation in uneven or shifting soil.

Additionally, HDPE pipes are lightweight, which simplifies handling and installation, especially in confined spaces. They can also be welded together, creating a strong, seamless structure that helps prevent leaks. The smooth interior surface of HDPE pipes reduces friction, allowing for better flow rates and efficiency.

While other materials like PVC and PEX have their advantages, HDPE's unique properties make it the preferred choice for underground piping systems, especially for applications involving water supply and wastewater management. Galvanized steel, while strong, is prone to rust and corrosion over time, making it less suitable for long-term underground use.