What to measure
Your water-use licence is the definitive list, but effluent monitoring at the discharge point typically covers:
- pH — the most common and fastest-moving compliance parameter
- COD (chemical oxygen demand) — organic load, critical for food, beverage and abattoir effluent
- Conductivity / TDS — dissolved salts
- Turbidity / suspended solids
- Flow — volume discharged, often a licence condition in its own right
- Temperature — and, depending on process, dissolved oxygen, ammonia or specific ions
How to put it in place
The sequence we follow on a DWS compliance project:
- 1. Read the licence. Extract the exact parameters, limits and reporting frequency for your discharge point — don't monitor more or less than required.
- 2. Instrument the discharge. Install online sensors for the licensed parameters at the final discharge point.
- 3. Log continuously. Stream readings to a platform that time-stamps and stores them, with edge buffering so load shedding doesn't create gaps in your record.
- 4. Alert on breach. Threshold alerts to WhatsApp or email, so an out-of-limit reading triggers action before it becomes an incident.
- 5. Automate the report. Generate the periodic compliance report straight from the logged data, in the format DWS expects.
Why load-shedding resilience matters for compliance
A gap in your monitoring record is a problem, not a neutral absence — it's exactly when a regulator asks "what was happening here?" If your monitoring goes dark every time the grid does, your compliance record is full of holes. Edge buffering — logging locally and syncing when power returns — keeps the record continuous through outages, which is why we treat it as a compliance requirement, not a nice-to-have, on South African sites.
This is the backbone of our water management solution and a core reason water utilities and industrial dischargers work with us. It runs on the addaNet platform, so effluent compliance sits alongside flow, energy and the rest of your operation.
One more distinction: where does your effluent go?
This guide covers discharge to the environment — a river, wetland or land — under a DWS water-use licence. If your effluent instead goes to the municipal sewer, you're under the local authority's bylaw and a trade-effluent permit, billed on volume and COD load, with a different (and separately monitored) set of limits — see trade-effluent monitoring. And if you're on the regulator's side of this data rather than the discharger's, see regulatory & catchment oversight.
The General Authorisation limits — general vs special
For discharge to a water resource under the 2013 General Authorisation (GN 665, Table 2.1), the limits that a continuous record is measured against are published. The special limits apply to listed sensitive resources; the notice states the values are subject to review as classification and resource quality objectives progress, so confirm the current condition on your licence or authorisation.
| Parameter | General limit | Special limit |
|---|
| Faecal coliforms (per 100 mL) | 1,000 | 0 |
| Chemical oxygen demand (mg/L) | 75 | 30 |
| pH | 5.5 – 9.5 | 5.5 – 7.5 |
| Ammonia as N (mg/L) | 6 | 2 |
| Nitrate/nitrite as N (mg/L) | 15 | 1.5 |
| Free chlorine (mg/L) | 0.25 | 0 |
| Suspended solids (mg/L) | 25 | 10 |
| Electrical conductivity | +70 mS/m above intake, max 150 | +50 mS/m above background, max 100 |
| Ortho-phosphate as P (mg/L) | 10 | 1 (median), 2.5 (max) |
| Soap, oil or grease (mg/L) | 2.5 | 0 |
| Dissolved iron / manganese (mg/L) | 0.3 / 0.1 | 0.3 / 0.1 |
| Dissolved zinc / copper (mg/L) | 0.1 / 0.01 | 0.04 / 0.002 |
Source: GN 665, Government Gazette 36820, 6 September 2013, Table 2.1 (selected parameters; the notice also lists arsenic, cadmium, chromium VI, cyanide, lead, mercury, selenium, fluoride and boron).
Frequently asked questions
What parameters does DWS require us to monitor?
It's defined by your specific water-use licence and discharge type, but effluent compliance commonly covers pH, COD, conductivity, turbidity, flow and temperature, sometimes with additional process-specific parameters. Always work from the parameters and limits stated in your own licence.
Can continuous monitoring replace lab grab-samples entirely?
It replaces the blind spots between samples and gives you real-time control, but most licences still require periodic accredited-lab verification. The practical model is continuous online monitoring for control and reporting, with lab samples for calibration and verification.
How does automated reporting actually work?
Because every reading is time-stamped and stored, the platform compiles the periodic compliance report directly from the data — values, exceedances and actions — in the format you submit, instead of someone rebuilding it from spreadsheets each month.
What happens if a parameter breaches a limit?
A threshold alert goes to the responsible person immediately via WhatsApp or email, so you can intervene — adjust dosing, divert flow, stop a process — before the excursion becomes a reportable incident, and the event and your response are logged.
Will the monitoring keep working during load shedding?
Yes, when it's designed for it. Edge devices buffer readings locally and sync when power and connectivity return, so your compliance record stays continuous through outages instead of showing gaps.