Skip to content
Wade's Plumbing & Septic logoWade's Plumbing& Septic

Septic Glossary

Trench Drain Field

Classic gravity leach lines built in excavated trenches with perforated pipe and gravel or approved aggregate to disperse septic effluent into undisturbed soil.

Trench Drain Field

Also called: Gravity trench field, Pipe and gravel field

What it means

Trench fields place perforated pipe on a bed of gravel within excavated trenches. Effluent seeps through pipe holes into gravel and then into soil for treatment.

Trench count, length, and spacing come from soil tests and setback rules. Crushed or silted gravel, collapsed pipe, and biomat clogging are common failure modes on older systems.

Why it matters in Santa Cruz County

Many pre-1990 Santa Cruz County homes use gravity trench fields on moderate slopes where deep, permeable soil was available at installation.

Homeowner tip

Avoid cutting trenches for irrigation or utilities through the field without locating pipes on the as-built plan first.

Related Wade's services

Also explore the Plumbing Glossary or call 831.225.4344 with questions about your property.