Blue Drop and Green Drop: A Guide for Municipalities

In short: Blue Drop and Green Drop are the Department of Water and Sanitation’s incentive-based regulation programmes for municipal water services. Blue Drop assesses how well drinking water systems are managed, and Green Drop assesses wastewater treatment. Both score the management systems behind the plant, not only the water quality on the day, so municipalities that plan, document, monitor and act on risks score better.

What are Blue Drop and Green Drop?

The Department of Water and Sanitation (DWS) started the Blue Drop and Green Drop programmes in 2008, and added No Drop in 2014. Together they are known as the Drop programmes. They assess every Water Services Authority, usually a municipality or metro, against set criteria and publish the results.

• Blue Drop covers drinking water supply systems, from abstraction and treatment to the water that reaches the tap.
• Green Drop covers wastewater collection and treatment works, and what is discharged back into rivers and the environment.
• No Drop covers water use efficiency, water losses and non-revenue water.

Systems that score very highly earn certification, which municipalities can show to residents, councillors and funders. Systems that score poorly are flagged, and DWS can require corrective action plans.

Where municipalities stand

The 2025 Green Drop report, released on 31 March 2026, assessed 848 wastewater treatment works. 396 of them (47%) were in a critical state, up from 39% in the previous report, and only 14 systems earned Green Drop certification. The Blue Drop and No Drop progress reports released at the same time showed only a marginal improvement in drinking water quality and a national average of 47% non-revenue water.

The gap is often not only about money or ageing infrastructure. Many low scores come from missing plans, incomplete records, untrained process controllers and risks that were identified but never acted on. Those are management system problems, and they can be fixed.

What the assessments look at

The exact criteria and weightings change from one assessment cycle to the next, so always work from the current DWS assessment guide. In broad terms, both programmes look at:

• Risk planning. A Water Safety Plan for drinking water (Blue Drop) and a Wastewater Risk Abatement Plan (W2RAP) for wastewater (Green Drop), kept up to date and actually used.
• Process management and control. Registered works, classified plants, qualified process controllers and supervisors, and operating procedures.
• Monitoring and compliance. Sampling programmes, tests at accredited laboratories, and results measured against SANS 241 for drinking water or the discharge limits in the works’ authorisation.
• Technical and asset management. Maintenance, capacity against demand, and how well the plant is looked after.
• Management, finance and accountability. Budgets, reporting, how incidents are handled and how the public is told.

How to prepare for a Blue Drop or Green Drop assessment

1. Know the current criteria. Get the latest DWS assessment guide and score yourself honestly against every requirement.
2. Bring your risk plans up to date. Review the Water Safety Plan or Wastewater Risk Abatement Plan, and make sure the control measures in it are really in place.
3. Fix the evidence trail. Assessors score what they can see. Logbooks, sampling records, lab certificates, maintenance records and training records need to be complete and easy to find.
4. Close the actions. Every failure, non-compliance and incident should have a recorded cause and a corrective action that was followed through. Our guide to root cause analysis explains how.
5. Run an internal audit first. An independent internal audit against the criteria shows the gaps while there is still time to close them.

How ISO standards support Blue Drop and Green Drop

Blue Drop and Green Drop are not ISO standards, but they reward the same habits. A quality management system to ISO 9001 gives you controlled documents, trained staff, internal audits and corrective action. ISO 14001 covers environmental risks and legal compliance, which matter for wastewater discharge. ISO 55001 covers the asset management that keeps plants running. Municipalities that already run these systems usually find the Drop assessments easier, because the evidence already exists.

Frequently asked questions

What is the difference between Blue Drop and Green Drop?

Blue Drop assesses drinking water supply systems. Green Drop assesses wastewater collection and treatment. Both are run by the Department of Water and Sanitation.

Who is assessed?

Water Services Authorities, which are mostly municipalities and metros. Each of their water supply systems and wastewater treatment works is scored separately.

Is Blue Drop or Green Drop certification compulsory?

Certification itself is an award for excellent performance. Taking part in the assessments is not optional for Water Services Authorities, and the results are published.

What is a Wastewater Risk Abatement Plan?

It is the wastewater equivalent of a Water Safety Plan. It identifies the risks across the collection and treatment system and sets out the controls and responses for each.

Can a municipality improve its score before the next assessment?

Yes. Updated risk plans, complete records, closed corrective actions and trained staff all count, and they can be put in place within months.

How Newfil helps

Newfil supports municipalities with Water Safety Plans, Wastewater Risk Abatement Plans (W2RAP) and Blue Drop and Green Drop readiness, from a team that includes current and former inspectors. We also implement the ISO management systems and run the internal audits and training that support them, on site. Read our water safety plan FAQ or book a free call to talk through your next assessment.