Thomas N. Ott, PE

Pirana Septic System Review: Can It Revive a Failing Leach Field?

A few years ago, I encountered a non-traditional septic system in Passaic County, New Jersey. The system was installed in a high-groundwater area—a stream ran along the property line—and the backyard was small. It was a mounded septic system with:

  • One settling tank
  • A pump dosing tank
  • A small pressure leach field

A Unique Addition: The Pirana System

What made this setup unique was the installation of a Pirana System, a submerged attached growth bioreactor (SAGB). This aerobic septic system modification turned what would have been a traditional anaerobic system (without oxygen) into an oxygenated system.