The Laboratory Division continuously monitors water quality of tap water from Macao water treatment plants, public water supply network in each district, reservoirs, raw water supplied to Macao, etc. to ensure the safety and stability of water quality of the public water supply system. According to Decree-Law no. 46/96/M “Regulations on Water Supply and Drainage in Macao”, analytical methods of international standards are adopted to carry out tests on physicochemical parameters, organic substances, ions, heavy metals, microorganisms, pesticide residues and radiation substances and other items in order to safeguard the public use of drinking water that meets hygiene standards.
In addition to the test items stipulated in “Regulations on Water Supply and Drainage in Macao”, the relevant drinking water quality standards of World Health Organization, European Union and Mainland China also serve as references. Other water quality indicators which receive wide attention are included in testing so as to strengthen the monitoring of drinking water quality.
Monitoring of Drinking water quality
Water samples are randomly collected daily from various water treatment plants, public water supply network in each district, reservoirs, raw water supplied to Macao, etc., After on-site tests of pH, conductivity and free residual chlorine, the samples are delivered promptly to the Laboratory for further analysis.
Workflow of monitoring:
- On-site sampling and tests:
- Collecting samples of drinking water
- On-site test: free residual chlorine, pH value, etc.
- Laboratory analysis
- Microbiological analysis: sample filtration and inoculation, bacteria cultivation, result interpretation.
- Chemical analysis: physicochemical parameters, metals and organic compounds, etc.
- Information collation and result dissemination
- Data processing and verification of information
- Test report compilation
- Release of water quality results on website