Recommendations from the Health Board
Drinking water quality monitoring and recommendations
In accordance with instructions from the Health Board, drinking water in Tallinna Vesi's service area is constantly monitored.
We have summarised the key points of these instructions below to give you confidence that the quality of the drinking water is carefully monitored.
Method of analysis
The quality of the drinking water we supply has remained high over the years.
In 2019, a more sensitive method of analysis was introduced for the assessment of coliforms, resulting in the detection of isolated coliforms. It is important to remember that this is only an indicator. The earlier analysis method usually failed to detect the bacteria.
There have been no recorded cases of people experiencing health issues in Tallinn, either historically or currently, that could be linked to the presence of coliform bacteria in the drinking water.
The quality of the drinking water itself has remained the same, but the method of testing it has become more accurate, sensitive, and faster. Similar changes in test results have also been seen in other countries
Results
The Health Board analysed:
- morbidity in areas where drinking water has been consumed over the years,
- the species of coliform bacteria found,
- the specifics of the method.
The coliform bacteria found in the water originate from the environment; for instance, they can be found in soil.
Isolated coliform bacteria
The presence of isolated coliform bacteria in drinking water indicates that the pipes need flushing. One way of ensuring that water is clean is to increase the level of chlorine in line with statutory limits, a measure that we have introduced in some areas.
The risk assessment prepared by the Health Board concludes that the presence of isolated coliform bacteria is unlikely to pose a health risk. However, as a precaution, stricter measures than usual will be applied to risk groups to ensure their adequate protection.
Recommendations from the Health Board
Based on the health risk assessment, the Health Board has recommended that we take the following action if coliform bacteria are found:
- 2–3 / 100 ml – we will notify the affected hospitals and nursing homes, as well as the Health Board, immediately. We take repeat samples and provide recommendations for action based on the test results obtained. There is no need to inform the rest of the population or implement any measures.
- 4 – ... / 100 ml – we will inform the affected hospitals and nursing homes, the Health Board and other affected customers. We take repeat samples and provide recommendations for action based on the test results obtained.
These recommendations only apply where all other microbiological indicators, including E. coli, comply with the required standards.
Coliform bacteria on the property
In some cases, the water quality in our network may be fully compliant with the required standards, yet coliform bacteria may still be present in samples taken from a property. In these cases, we will notify the property owner and ask them to maintain their pipes.
If a non-compliance is found in our system, we will flush the pipes.
If coliform bacteria are found in repeat samples taken to check water quality, we recommend that customers boil the water before drinking it or using it for cooking as a precautionary measure to avoid any risk.
Maintaining consistently high water quality and protecting human health are priorities for us. We therefore follow the recommendations set out in the Health Board's risk assessment and notify our customers of any findings, in line with the principles described above.
