What material is commonly used for a septic tank?

Concrete is commonly used for septic tanks due to its durability, strength, and resistance to external pressures, making it well-suited for underground use. Unlike materials such as wood, which can rot and degrade over time when exposed to moisture and the corrosive effects of sewage, concrete provides a robust and long-lasting containment solution.

Additionally, concrete septic tanks can withstand the pressures from the surrounding soil and groundwater, which is essential to prevent leakage and ensure proper function. Unlike brick, which can allow gaps and may not hold the necessary weight, and paper, which would disintegrate in a moist environment, concrete holds up well in the conditions where septic tanks are installed. Thus, concrete is the preferred choice among installers for its reliability and longevity.