Septic Tank or Sewage Treatment Plant?

Septic tank or sewage treatment plant? They sound similar but they do different jobs, and choosing the right one comes down to your ground. Here is how to tell them apart.

The difference, simply put

A septic tank separates solids from liquid and lets the liquid soak away through a drainage field. It does not clean the water to a high standard, so it cannot legally discharge to a watercourse.

A sewage treatment plant goes a step further, using an aeration process to treat the liquid to around 95% clean — clean enough to discharge to a watercourse where a soakaway is not an option.

Which one do you need?

• Septic tank with a soakaway — the right choice if your ground passes a percolation test and there is space for a compliant drainage field.
• Treatment plant — the answer when your ground will not take a soakaway (heavy clay or a high water table), or there is a watercourse nearby to discharge to.

Not sure? That is what we are for

You do not need to work this out yourself. We assess the ground, run the test, and design the right solution — whether that is a septic tank, a treatment plant, or a new soakaway.