Water Quality
The Central Water Authority (CWA) is responsible for providing safe and quality drinking water to the people of Mauritius.
A key part of this responsibility is ensuring that the water supplied to households, businesses, and industries meets strict national quality standards.
Our Commitment to Safe Drinking Water
Under the CWA Act, the Authority has a legal obligation to ensure that treated water supplied to the public complies with national drinking water standards established under the Environment Protection Act regulations.
To meet this obligation, the CWA operates a well equipped and professionally staffed laboratory dedicated to water quality monitoring and scientific analysis. The CWA Water Quality Laboratory is based at the CWA Head Office, St Paul.
The Laboratory is accredited to ISO/IEC 17025:2017, the international standard for testing laboratories. This accreditation demonstrates that our testing methods are reliable, accurate, and internationally recognised.
What We Do
- Routine Water Quality Monitoring
Water samples are systematically collected from approximately 160 sampling points across the island to verify compliance with national standards. Water samples are collected from the entire distribution network from source to consumer tap which include;
- Water Treatment plants and Containerized Pressure Filters
- Service reservoirs
- Boreholes
- The distribution network and consumer premises
- Monitoring of Raw Water Sources
All raw water sources such as impounding reservoirs, boreholes and rivers used for domestic supply are tested regularly.
New sources are carefully analysed before being brought into service.
This ensures early detection of contamination and helps us monitor long-term water quality trends.
- Comprehensive Laboratory Analysis
Our qualified and trained laboratory professionals analyse a wide range of water quality parameters which can be grouped as follows:
- Microbiological indicators such as Total Coliforms and E. coli
- Physical and chemical properties, including main anions and cations, nutrients, and trace metals
- Microalgae identification and enumeration, with capability to identify up to 100 genera in raw water
This comprehensive testing ensures that water is safe for human consumption.
- Responding to Water Quality Concerns
The CWA Laboratory investigates and responds to water quality complaints from the public, and the Ministry of Health and Wellness which is the Enforcing Agency for drinking water under the Environment Protection Act.
We are committed to addressing concerns promptly and providing clear, science-based explanations.
- Disinfection and Infrastructure Safety
The laboratory also conducts testing related to:
- Cleaning and disinfection of pipelines
- Reservoir maintenance
- Water storage tank sanitation
These measures help maintain the safety and integrity of the water supply system.
- Supporting National Environmental Goals
Beyond routine testing, the laboratory contributes to protection of environmental waters and sustainable development by:
- Participating in Environmental Impact Assessments (EIA), Preliminary Environmental Reports (PER), Environmental Monitoring Plans (EMP), and Strategic Environmental Assessments (SEA)
- Providing water quality reports for groundwater licence applications and renewals
- Collaborating with the Ministry of Energy and Public Utilities/Water Resources Commission, the University of Mauritius, the Ministry of Environment and Sustainable Development and the Ministry of Health and Wellness on research and water protection initiatives
Frequently Asked Questions (FAQ)
Yes. Water supplied by the CWA is treated and tested regularly to ensure it meets national Drinking Water Standards. Continuous laboratory monitoring ensures that the water is safe for consumption.
Water is tested regularly throughout the year at approximately 160 sampling points across the island. Both treated water and raw water sources are monitored.
ISO/IEC 17025:2017 is an international standard for testing laboratories. Accreditation confirms that the CWA Laboratory is technically competent and produces accurate and reliable results.
If you notice any unusual colour, taste, or smell in your water, you should contact the CWA Hotline on 170 or any customer service centre. The laboratory will investigate the issue if necessary.
Yes. The laboratory routinely tests for microbiological indicators such as Total Coliforms and E. coli, which help confirm that the water is safe for drinking.
Yes. All new borehole and reservoir raw water sources are thoroughly tested before being used for public supply to ensure they meet required safety standards.
Members of the public may contact the CWA for guidance regarding water quality concerns. Depending on the nature of the request, further testing may be arranged.
Contact Us
- +230 601 5000
- cwa@intnet.mu
- Hotline : 170
Our team is available to assist you and respond to enquiries professionally and promptly.
Protecting Public Health Every Day
Through continuous monitoring, advanced laboratory analysis, and strict compliance with national regulations, the CWA Laboratory plays a vital role in safeguarding public health.
Our mission is simple: to ensure that the water you receive is safe, clean, and of the highest quality.
- Accreditation & Certification
The Central Water Authority Laboratory is accredited to ISO/IEC 17025:2017, the international standard for testing and calibration laboratories. This accreditation confirms our technical competence and the reliability of our test results.
For full transparency, members of the public may view our official accreditation documents below:
- Schedule of Accreditation – (View / Download PDF)
- Accreditation Certificate – (View/Download PDF)
These documents detail the specific tests and parameters for which the laboratory is formally accredited.
Commercial services.
The laboratory also provides its services to the public, external agents and institutions against payment of fees at approved rates.
Useful links
Members of the public can also have access to other relevant information through the links below;
- Guidance notes on disinfection of household tanks (View/Download PDF)
- Water Testing and Reporting (View/Download PDF)
- Drinking Water Standards – (View/Download PDF)
Last updated : 5 March 2026.