Water treatment plant monitoring — see every stage, dose and discharge in real time.

A water treatment plant only does its job if every stage holds — coagulation, filtration, chlorination, aeration, settling — and the only way to know is to measure it continuously. addanode puts IoT water sensors across drinking-water and waste water treatment plants, tracks chemical dosing and COD load, alerts you before quality drifts out of range, and turns final-effluent data into the DWS compliance reports you have to file — all on the in-house addaNet platform, built to keep running through load shedding.

What this is

Continuous IoT monitoring for water and waste water treatment plants.

We don't design the chemistry or run the works — your process engineers and operators do that. What we add is instrumentation and visibility: a layer of water sensors, edge devices and dashboards that tells you, minute by minute, whether each treatment stage is performing, whether dosing is on target, and whether the water leaving the plant is safe and compliant. It applies equally to a drinking-water treatment works (WTW) and a wastewater treatment works (WWTW).

Drinking-water treatment works (WTW)

From raw-water intake through coagulation, clarification, filtration and chlorination to the final treated-water reservoir. Monitor turbidity removal, coagulant and lime dosing, filter performance and chlorine residual so treated water meets SANS 241 before it ever reaches a consumer.

Water quality & compliance →

Wastewater treatment works (WWTW)

From influent screening through primary settling, biological aeration and clarification to disinfection and final discharge. Track COD and BOD load, dissolved oxygen in the aeration basins, and final-effluent quality so discharge stays inside your water-use licence and doesn't pollute the receiving river.

Wastewater monitoring guide →
What we put on the plant

Sensors, dosing telemetry and compliance — one platform.

Typical water sensors & signals:

Turbidity (NTU) pH Dissolved oxygen (DO) COD BOD load Free & total chlorine Conductivity / TDS Ammonia & nitrate Suspended solids Flow & level Dosing-pump rate Chemical tank level

Compliance regimes we report against:

DWS water-use licence SANS 241 (drinking water) Blue Drop Green Drop General & special effluent limits

Regulatory references are for orientation; confirm current requirements against your water-use licence, the latest DWS guidance and your appointed advisers.

The parameters that matter

What to monitor, what it tells you, and where.

You don't need a sensor on everything. The value is in measuring the handful of parameters that tell you whether each treatment stage is doing its job — and catching the moment one of them moves.

ParameterWhat it tells youTreatment stage
Raw-water turbidityIncoming load on the plant — how hard coagulation and filtration have to work, and whether to adjust dosing.Raw-water intake (WTW)
Coagulant / flocculant doseWhether you're using the right amount of chemical to drop solids out — under-dosing lets turbidity through, over-dosing wastes Rand.Coagulation & flocculation (WTW)
pH & lime doseWhether water is in the right pH band for coagulation, corrosion control and downstream disinfection.pH correction (WTW & WWTW)
Settled / filtered turbidityWhether clarifiers and filters are removing solids — the front-line indicator of treated-water clarity.Clarification & filtration (WTW)
Chlorine residualWhether disinfection is sufficient to make water microbiologically safe — and not so high it creates by-products.Chlorination / disinfection
Dissolved oxygen (DO)Whether the biology in the aeration basin has enough oxygen to break down organic load — the single biggest energy cost on a WWTW.Biological aeration (WWTW)
COD & BODThe organic pollutant load entering and leaving the plant — how much work the biology must do, and whether effluent is clean enough to discharge.Influent & final effluent (WWTW)
Ammonia & nitrateWhether nitrification/denitrification is working — key nutrient-removal indicators for licence compliance.Biological treatment (WWTW)
Final-effluent qualityThe number that matters legally — COD, suspended solids, pH, ammonia and more against your discharge limits.Final discharge (WWTW)
Flow & levelHydraulic load and whether the plant is within its design capacity — overload risk during storms or peak demand.Throughout
Water treatment chemicals

Monitor dosing and chemical stock — for quality and for cost.

Every treatment plant runs on water treatment chemicals: coagulants and flocculants to drop solids out, lime and other reagents for pH correction, and chlorine or other disinfectants to make water safe. Dosing them correctly is the difference between compliant water and a breach — and between a controlled chemical bill and a runaway one. Yet on many works, dosing is checked manually and chemical stock is discovered empty only when a tank runs dry.

Dosing rates

Monitor dosing-pump output against flow and incoming load, so the dose tracks demand instead of a fixed setpoint that's wrong half the day.

Over- & under-dosing alerts

Under-dosing lets turbidity or pathogens through; over-dosing wastes chemical and can create its own compliance problem. Alerts catch both.

Chemical tank / stock levels

Level sensors on dosing tanks and bulk storage warn you before a tank runs dry — and feed reorder planning so you never dose blind.

Chlorination control

Tie chlorine-residual sensing to dosing so disinfection stays in band as flow and demand swing through the day.

Cost control

Chemicals are a large, controllable cost. Matching dose to actual load — not worst-case — trims the bill without risking quality.

Dosing-pump health

A failed or drifting dosing pump silently sends water through untreated. Status and runtime monitoring flags it before the lab does.

COD in water treatment

COD — the central pollutant-load parameter.

Chemical Oxygen Demand (COD) measures how much oxygen it would take to chemically oxidise the organic and oxidisable matter in water. In plain terms, it's a single number for "how dirty is this water" — the higher the COD, the greater the pollutant load. That makes it the workhorse parameter of waste water treatment: it tells you the load coming into the plant, how hard the biology has to work, and whether the final effluent is clean enough to discharge.

COD vs BOD. Biochemical Oxygen Demand (BOD) measures the oxygen micro-organisms need to break down the biodegradable fraction over five days. COD captures a broader range of oxidisable matter and returns a result in minutes to hours rather than days. The COD:BOD ratio is itself diagnostic — a high ratio suggests a large non-biodegradable or industrial component that biological treatment alone won't remove.

Online vs lab. Lab COD is the legal reference, but a sample taken once a day tells you nothing about the other 23 hours. Online or continuous COD-correlated sensing fills the gap: it trends load in real time, flags a slug of incoming organic load before it upsets the biology, and shows whether the plant recovered — with the lab result as the periodic anchor.

Why COD earns its place on the dashboard: it's the one parameter that links influent load, biological performance and discharge compliance in a single trend. Watch COD across the plant and you can see a problem forming — an industrial discharge upstream, a failing aeration blower, a wash-out event — hours before it shows up as a non-compliant final effluent.

Why it matters

Two outcomes: water safety in, pollution out.

Water safety — protect the consumer

On a drinking-water works, the job is non-negotiable: water leaving the plant must be safe. Continuous turbidity and chlorine-residual monitoring against SANS 241 limits — with breach alerts the moment a value drifts — means an operator knows about a disinfection or filtration problem in minutes, not when a Blue Drop audit sample comes back. Catching unsafe water before it reaches the reservoir is the whole point.

Water quality sensors explained →

Water pollution — protect the river

On a wastewater works, the risk runs the other way: non-compliant effluent discharged to a river is water pollution, a licence breach and a Green Drop failure. Continuous COD, suspended-solids, ammonia and pH monitoring on the final effluent — with alerts set inside your licence limits — lets you act on drift before a slug of poorly treated water leaves the plant and pollutes the receiving environment.

Environmental monitoring →
Equipment health

The plant only treats water if the machines run.

Treatment performance and equipment health are the same problem seen from two ends. A blower that's losing output starves the aeration basin of oxygen and COD removal collapses; a tripped transfer pump backs water up; a dosing pump that's drifted off sends water through under-treated. Monitoring the equipment alongside the process means you see the cause, not just the symptom.

Pumps

Run status, energy, vibration and runtime on intake, transfer and return-activated-sludge pumps — catch a bearing or seal failure before it stops flow.

Blowers

The biggest energy user on a WWTW and the heart of aeration — monitor output and energy so DO and COD removal don't quietly degrade.

Dosing pumps

Status and rate so a stalled or drifting dosing pump becomes an alert, not a lab surprise three days later.

This is the same condition-monitoring approach we apply across industrial IoT and asset monitoring — applied to the rotating equipment that keeps a treatment works alive.

How it works

Sensor to dashboard to DWS report — read what you already have.

1 · Sense the stages

Water sensors and dosing telemetry at the points that matter — intake, dosing, aeration, filtration, disinfection and final effluent — integrated with the analysers and PLCs you already run (Modbus, OPC-UA, 4–20 mA) rather than ripped out.

2 · Buffer at the edge

Edge devices log locally and sync when power and connectivity return, so a final-effluent record is never lost to load shedding — the gap that would otherwise sink your compliance data.

3 · Visualise & alert

One real-time dashboard for the whole works — process, dosing, equipment and compliance — with threshold alerts to WhatsApp or email the moment a parameter moves out of range.

4 · Report & act

Final-effluent logs become the DWS submission automatically, and process trends become prioritised operator actions — data that drives a decision, not just a chart.

It all runs on the in-house addaNet platform, so your treatment-plant data sits alongside network, reservoir and non-revenue-water data in one operational picture.

Why addanode for treatment-plant monitoring

Built for South African works, power and the regulator.

Engineered for the conditions a treatment works actually operates in: edge buffering and solar-ready hardware so monitoring and compliance logging survive load shedding; connectivity matched to the site (LoRaWAN, NB-IoT, 4G, wired); integration with the instruments and PLCs already on the plant; and compliance aligned to DWS water-use licences, SANS 241, Blue Drop and Green Drop. Because we build both the hardware and the software in-house and support it locally, we scope for the parameter, the dose or the discharge limit that matters most — and start where it pays back fastest.

Frequently asked

Treatment-plant monitoring questions.

Most treatment-works projects start with one driver: a compliance risk on the final effluent, a runaway chemical bill, or a quality scare. Here's how we approach the common ones.

It means placing water sensors and dosing telemetry across each treatment stage — raw-water turbidity, coagulant and lime dosing, pH, filtration, chlorine residual, dissolved oxygen, COD/BOD and final-effluent quality — and streaming it to one real-time dashboard with alerts. We monitor; your operators run the process. The data shows whether each stage is performing and whether treated water is safe and compliant.
Yes. We monitor dosing-pump rates, chemical tank and bulk-stock levels, and tie dosing to flow and quality sensors so over- and under-dosing both raise alerts. That protects water quality and controls the chemical bill — and a level sensor warns you before a dosing tank runs dry rather than after.
Chemical Oxygen Demand (COD) measures the oxygen needed to chemically oxidise the organic matter in water — effectively a single number for pollutant load. It's central to waste water treatment because it shows the load entering the plant, how hard the biology must work, and whether final effluent is clean enough to discharge. Online COD trends load in real time between lab samples and warns of a problem hours before a breach.
Two directions. On drinking-water works, continuous turbidity and chlorine monitoring against SANS 241 catches unsafe water before it reaches consumers. On wastewater works, continuous COD, solids, ammonia and pH monitoring on the final effluent catches non-compliant discharge before it pollutes a river. In both cases alerts are set inside your limits, so you act on drift rather than on a breach.
Yes. The same platform covers drinking-water treatment works (WTW) — coagulation, filtration, chlorination against SANS 241 and Blue Drop — and wastewater treatment works (WWTW) — aeration, COD/BOD removal and final-effluent compliance against your water-use licence and Green Drop. Only the parameters and limits change; the sensing, edge buffering, dashboard and reporting are the same.
Yes. Edge devices buffer readings locally and sync when power and connectivity return, and hardware can run on solar where needed. That means your process trends and — critically — your final-effluent compliance record stay continuous across an outage, with no gap to explain to DWS or an auditor.

Prove your treatment plant is performing — automatically.

Tell us your works and your worry — final-effluent COD, chemical dosing cost, a chlorine-residual scare. We'll scope the water sensors, the dosing telemetry and the DWS compliance dashboard, and tell you where to start.