150 years of engineering.
3 fundamental methods.

Every municipal wastewater plant on the planet uses one of three biological treatment paths — or a hybrid. The branches grew over a century; the roots haven't changed. Click around to see them all.

WASTE WATER SUSPENDED growth CAS · SBR · MBR ATTACHED growth MBBR · IFAS · TF LAGOONS + wetlands facultative · aerated
The tech tree

Click any node to drill in

Five families, twenty-something variants. Each node opens a detail card on the right: how it works, where it shines, where it doesn't, and which neighbours to look at. Coloured by family.

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Pick a node to begin

Click a family on the left, then a variant. Or jump straight into a leaf — every tech card cross-links to its closest cousins.


Family feud · activated sludge

CAS vs Carrousel — same family, different geometry

Both grow bacteria in suspension to eat the organics. Conventional Activated Sludge uses rectangular tanks with bottom diffusers. Carrousel (oxidation ditch) uses an oval racetrack with surface aerators. Toggle the lens to see which one wins on what.

Geometry A

Conventional Activated Sludge (CAS)

aerated zone settler
Geometry B

Carrousel (Oxidation Ditch)

aerator in out horizontal circulation · simultaneous nitri/denitri

Mini-quiz · 5 questions

Spot the technology

A schematic, a description, four options. Click your guess — we'll tell you why. Beats memorising 11 acronyms cold.

Question 1 of 5
Score: 0 / 5


Tech selector

Tell us about your plant — we'll suggest a stack

Three knobs: size, effluent target, and reuse purpose. The recommendation updates live. Not a sales pitch — just the design pattern most engineers default to for that combination.

Your plant

Daily flow
Effluent target
Footprint constraint
Climate

Recommended stack

Also consider