Advanced & Tertiary Septic Treatment Systems
Not every property suits a conventional septic bed. Advanced and tertiary treatment systems can reduce the bed footprint or handle site conditions a standard system can't — where the site suits them. Slegh Septics has experience with these applications across Southern Ontario.

When an advanced system makes sense
Advanced and tertiary treatment systems treat effluent to a higher standard before it reaches the ground. That higher level of treatment can open up options on properties where a conventional system is difficult — but they aren't a fix for every situation, and we won't promise they are.
They're often worth considering on:
- Restricted or small lot sizes
- Difficult site conditions and soils
- Projects where a reduced bed footprint helps
- High daily design flows
- Commercial properties and developments with site constraints
Systems we're certified to install
Slegh Septics is a qualified and certified installer for several leading advanced treatment and leaching systems. The right unit for a given property depends on the design flow, the site and the approval requirements — that's determined during design, not chosen off a shelf.
- Waterloo Biofilter — qualified installer
- Ecoflo — certified installer
- Eljen — system installer
A difficult property doesn't automatically need an advanced system, and an advanced system won't solve every site problem. We'll give you a straight answer on what your site actually calls for.
Designed and installed as one project
Advanced systems have more moving parts — treatment units, controls, sometimes pumps and alarms. Having the same team design and install the system keeps those parts working together and keeps the project accountable to one contractor.
Frequently asked questions
A tertiary treatment system treats effluent to a higher standard than a conventional system before it's dispersed. That can allow a smaller dispersal area or make a difficult site workable — depending on the property and approval requirements.
It's typically considered when the site is constrained, the soils are difficult, or the design flow is high. Whether one is required or beneficial is determined during the design based on your specific property.
Yes. Slegh Septics is a qualified and certified installer for Waterloo Biofilter, Ecoflo and Eljen systems. Which system suits your property is determined during design, based on the site and the design flow.
Certified For The Systems We Install
We're a qualified and certified installer for leading advanced treatment systems — so we can match the right system to your site.



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