Well Casing
Definition
Well casing is the tubular lining placed inside a drilled borehole after drilling is complete. It serves three critical functions: structural support (preventing the borehole wall from collapsing), contamination protection (keeping surface water, soil, and bacteria from entering the well), and pump housing (providing the conduit through which the pump, electrical line, and water supply pipe are installed). In Idaho, casing must meet IDWR standards for material, wall thickness, diameter, and installation method. Steel casing is standard in hard rock and deeper wells; PVC or thermoplastic casing is used in some formation types at shallower depths. Casing extends from the surface down through the unconsolidated zone and into stable bedrock or the aquifer zone.
Frequently Asked Questions
Why Well Casing Matters
How Trident Drilling Company Uses It
Trident Drilling selects casing material and diameter based on well depth, geological conditions, and intended use for each project. Steel casing is standard for the deeper wells and hard rock conditions common in Northern Idaho; PVC is selected where formation and depth conditions support it. All casing installations comply with IDWR standards, including minimum depth and wall thickness requirements. The annular space between the casing and borehole wall is sealed with grout immediately after installation.