How to start
- Rank by failure consequence. Which upset or equipment failure most often pushes you out of spec or risks an overflow? Start there — usually aeration/DO and the critical pumps and blowers.
- Instrument those points — integrating with the instruments and PLCs the works already has wherever possible, not a rip-and-replace.
- Alarm to a named owner. A DO crash or a blower trip must reach the responsible person immediately, with an escalation path — not sit on a screen no one watches at 2am.
- Log for compliance. Continuous final-effluent logging becomes your licence and Green Drop evidence — defensible and exportable.
- Optimise once stable. With DO and flow visible, run blowers to demand (a major energy cost) instead of flat-out, and tune the process on data.
Built for South African works
Two local realities shape the design. Load shedding can stop aeration and pumping, so monitoring must keep recording through outages (edge buffering) and alarm on power loss, and the data helps you size and prioritise backup power for critical stages. Remote and unmanned works need monitoring that reaches them — low-power connectivity and, where needed, solar power — so a small or distant works gets the same visibility as the main plant without a permanent operator on site.
This is part of addanode's water management work on the in-house addaNet platform — process, equipment, chemical dosing and final-effluent quality and DWS compliance in one picture, with alarms and continuous records, engineered to keep working through South African power and connectivity. The same approach covers a clean-water water treatment plant monitoring brief, where dosing and process quality matter just as much. It complements your operators and sampling regime rather than replacing the professional judgement that runs the works.
Regulatory references are for orientation; confirm current obligations against your water-use licence, the latest DWS / Green Drop requirements and your appointed advisers.
What to monitor at each stage of the works
| Stage | Parameters | What a deviation tells you |
|---|
| Inlet works | Inflow, screen differential level | Storm inflow/infiltration; blinded screens |
| Aeration / biological reactor | Dissolved oxygen, blower current, ammonia | Blower failure before the biology dies; under- or over-aeration |
| Clarifiers | Sludge blanket level, suspended solids | Solids carry-over into final effluent |
| Disinfection | Chlorine residual (or UV intensity), contact-tank flow | Under-dosing → coliform failure; over-dosing → free-chlorine breach |
| Final effluent | COD, suspended solids, ammonia, pH, E. coli, flow | Compliance against GN 665 limits; the record Green Drop scores |
| Utilities | Mains presence, generator state, pump currents | Load shedding response; silent pump failure |
Frequently asked questions
What should we monitor on a wastewater treatment works?
The things that run and protect the process: inflow and hydraulic load, dissolved oxygen in the biological stage, pump and blower health and run-status, levels and overflow risk, and final-effluent quality (pH, COD, turbidity and your licence parameters). Start with the failure points that most often push you out of spec — usually aeration and critical pumps and blowers.
How does this help with Green Drop and our water-use licence?
Continuous final-effluent logging gives you defensible, exportable compliance evidence, and process alarms let you correct an upset before it becomes a non-compliant discharge. That supports DWS / Green Drop performance far better than relying on periodic samples that can miss an excursion between visits.
Does real-time monitoring replace our samples and operators?
No — it complements them. Live monitoring shows what the process is doing between samples and alerts on upsets, while laboratory samples and your operators' judgement remain central to running and certifying the works. The technology widens visibility; the professionals still govern.
Can it reduce our energy bill?
Yes. Aeration blowers are typically the biggest energy cost on a works, and running them flat-out wastes power. With dissolved oxygen and flow monitored, you can run blowers to actual demand — cutting energy while keeping the process in its target band.
Will it keep working through load shedding and at remote works?
Yes, if designed for it. Edge buffering keeps the record continuous through outages and alarms on power loss, and low-power connectivity with solar where needed brings remote or unmanned works onto the same dashboard as the main plant — important given how outages disrupt aeration and pumping.
Worried about a works drifting out of spec?
Tell us about your works and where it's most fragile. We'll scope real-time monitoring on the failure points that matter — with alarms to the right people and compliance logging built in.