Conventional Septic Systems

conventional-septicThe most common septic bed is called a Conventional Septic Bed. It is also referred to as a Tile Bed, a Leaching Bed or Leach Field.

A Conventional Bed is made up of two basic components. A Septic Tank, for solids and scum, and a Tile Bed for effluent to drain into. The Ontario Building Code (OBC) calls a Septic Tank a Treatment Unit and the drain field as a Leaching Bed.

Conventional Septic Beds incorporate a standard Septic Tank as their treatment unit and then the effluent is fed by gravity to a series of piping with holes drilled in them called weeping tile. Clay tiles are not used anymore, but the name “tile” has stuck with the industry.

Most pipes are PVC plastic with a series of holes drilled in the bottom to allow the waste water to flow into the pipe and into the gravel surrounding the pipe. New systems must have an effluent filter that captures any remaining floating suspended solids and keeps them from entering the actual tile bed. Too many solids in the drain field will dramatically accelerate the wear of the trenches in the septic bed.

The trenches for piping are dug about 30cm to 90cm deep, 50cm to 100cm wide and no closer than 1.6m apart. With a little luck and some planning the whole system will drain by gravity.

Some treatment of the waste happens in the septic tank, while the majority of the treatment happens in the tile bed. It is in the tile bed where oxygen is introduced to the wastewater via the soil, and the aerobic treatment happens in the soil and in the gravel bed. There is a fairly high nutrient loading rate (nitrates and phosphates) and these beds must remain unsaturated (above the water table) to ensure that no groundwater is polluted with raw effluent.

All of the clearance distances are taken from the piping, and since there is a large amount of piping involved, the owner ends up with a large amount of unusable space on his property.

extended leaching bed septic system

These are definitely the simplest systems, and this is the first choice of people when considering a septic system. However, due to more stringent regulations, these systems are rapidly becoming illegal to install and repair in many areas of Ontario.

To contact Slagter Construction regarding your septic system, please email us at:

Or simply fill out the form in the right column and we’ll contact you within 1 to 2 business days or sooner for emergencies.