1. Health risk
1. Can I drink tap water?
The water that SWDE distributes meets all EU and Walloon health standards.
2. What is the risk of ingesting asbestos? Do we risk the same effects as when we inhale asbestos?
While the risk of asbestos inhalation has been clearly identified for decades, the same cannot be said for asbestos ingestion, for which the risk is not yet known. To date, there are no EU standards or Walloon legislation on the subject, which is explained by the reassuring conclusions of scientific studies and the World Health Organization (WHO).
3. Can tap water contain asbestos?
Rarely and in very small quantities. 90% of the pipes in SWDE network are not made of asbestos cement but of other materials (steel, ductile iron, grey iron, PVC, polyethylene, etc.).
There is therefore no risk of water containing asbestos fibres when the water flows through pipes that are not made of asbestos cement.
When water flows through an asbestos cement pipe, it is possible, under very specific conditions, for asbestos fibres to be released into the water. In this case, the quantities released are infinitesimally small.
4. How can it be said that asbestos cement pipes do not cause the presence of asbestos in tap water?
The various analyses that SWDE carries out via an accredited laboratory on its customers' taps show that no asbestos fibres have been detected.
5. Do asbestos cement pipes pose a health risk?
According to current scientific knowledge, the levels of asbestos fibres found in water do not constitute a health hazard. This is why the European Union has not adopted any regulations in this area.
With the decree of 1 June 2023 amending various provisions concerning the quality of water intended for human consumption, Wallonia has chosen to go further by setting a guide value of 1 million fibres per litre using a method derived from NFX 43-050, with a quantification limit of less than or equal to 10,000 fibres per litre.
The United States has set a health standard of 7 million fibres per litre.
SWDE has never encountered such levels in the water analyses it carries out after taking samples from its customers' taps.
6. Can I inhale asbestos from tap water?
Under certain conditions, water intended for human consumption can be aerosolised (air from showers, etc.) and inhaled in very small quantities. As the asbestos fibre content in the tap water is zero or particularly low, the amount of asbestos fibre inhaled would be minuscule.
7. Won't the wear and tear of the asbestos cement pipes cause even more asbestos to be released into the water?
SWDE monitors our asbestos cement pipe network through targeted analysis campaigns. If abnormal wear and tear of our pipes were to endanger the health safety of our customers, the SWDE would make every effort to renew them as a matter of priority.
8. Can roof, cistern or well water contain asbestos?
Water that comes into direct contact with asbestos cement materials could, under certain conditions, contain asbestos fibres. For example, if the asbestos cement material is brittle (degraded by temperature variations between winter and summer) and the water that comes into contact with it has aggressive properties (which is characteristic of rainwater), then it is possible for the water collected to contain asbestos fibres.
The risk of harvested rainwater containing asbestos is therefore much higher than that for tap water.
9. Does SWDE test for asbestos in all municipalities?
There are municipalities where there are no asbestos cement pipes. It is therefore unnecessary to carry out special tests in these municipalities. Since September 2023, SWDE, with the support of the Walloon region, has taken the initiative of carrying out water quality checks in every municipality served by SWDE where part of the network is made of asbestos cement.
10. Can I request a free analysis?
SWDE can accommodate special requests for analysis within the framework of the current sampling campaign, as long as they are representative enough.
If the request cannot be part of a sampling campaign, the customer can request a water quality test at their own expense from a specialised laboratory.
11. What is the treatment to remove asbestos from water?
The asbestos fibre content in the water supply is zero or very low. It is therefore not necessary to treat the water.
12. Why check at hydrants and not just at customers' taps?
The only point of compliance for water intended for human consumption is our customers' kitchen taps.
As part of an internal study conducted in 2018, we carried out water quality checks both at hydrants and also at our customers’ meters and kitchen taps. Samples taken at the hydrants do not provide a representative picture of the quality of the water distributed to our customers.
Our sampling campaigns now target our customers' taps to obtain a representative picture of the water consumed by our customers.
13. Why do your checks show that the asbestos found at the hydrants is not found at the taps?
Hydrants have a dead volume between the pipe and the hydrant outlet. The water contained in the dead volume is stagnant and particles can become lodged there. When we take samples at hydrants, the sample taken may not be representative of the water actually distributed to our customers, because some of the water taken is stagnant water containing certain particles, including asbestos fibres.
The only point of compliance for water intended for human consumption is our customers' kitchen taps. As part of an internal study conducted in 2018, we carried out water quality checks both at hydrants and also at our customers’ meters and kitchen taps. Samples taken at the hydrants do not provide a representative picture of the quality of the water distributed to our customers. Our sampling campaigns now target our customers' taps to obtain a representative picture of the water consumed by our customers.
14. Is it dangerous to wash clothes with tap water containing asbestos?
The asbestos fibre content in the water is, where applicable, infinitesimally small. It is therefore not dangerous to wash your clothes with tap water supplied through asbestos cement pipes, as the risk of finding asbestos fibres on your clothes is very limited.
2. Information.
15. Why did you hide the positive asbestos water tests?
Water analyses showing the presence of asbestos fibres in the water have not been hidden. The positive tests were not specifically communicated because they did not relate to the water in the customers' taps. SWDE has provided this data in a transparent manner when requested.
16. What information will you be providing? Will you publish your new analyses?
SWDE is currently conducting a new water quality monitoring campaign. The results obtained are communicated to the municipalities and the Walloon Region.
17. Will I be warned if there is asbestos in my tap water?
If the analysis campaigns we carry out reveal a health risk for our customers, a specific communication will be sent to the customers concerned.
18. Why did you hide the presence of asbestos cement pipes?
SWDE has never made a secret of the presence of asbestos cement pipes. The FAQ tab on its website (swde.be under "Frequently Asked Questions") has been openly addressing the subject for many years.
19. Why not disclose the streets where these pipes are located?
In its computerised mapping system, SWDE has the nature (material) of all the pipes in its networks, including those made of asbestos cement. The exact mapping of the pipelines is not provided for reasons of network integrity and public safety. Neither a diagram nor a list of streets is representative of a risk related to water quality as it flows through the pipes, since, for example, there may be pipes constructed of different materials in the same street.
3. Pipes
20. Why are there asbestos cement pipes?
In the aftermath of the 2nd World War (1940-1945), the demand for building materials was enormous and many small and medium-sized municipalities were equipped with a drinking water network. Asbestos cement pipes produced in Belgium were an innovative alternative to the much sought-after materials steel and grey cast iron. In addition to being lighter, asbestos cement pipes had useful characteristics in terms of compressive strength, tensile strength and bending strength, as well as an absence of internal corrosion which, with metal pipes, can cause coloured water over time.
No more asbestos cement pipes have been laid since the late 1970s.
21. Where are asbestos cement pipes laid?
The distribution of this type of pipe throughout Walloon territory is not uniform, as some municipalities have a network composed of a high percentage of asbestos cement pipes, while others have none at all.
In its computerised mapping system, SWDE has the location, nature (material) and other characteristics such as diameter, date of laying, etc. of all the pipes in its networks, including those made of asbestos cement.
22. How does SWDE know the nature of the distribution pipes?
When pipe-laying work is carried out, a survey plan is drawn up at the end of the works. It lists all the components of the network (pipes, valves, hydrants, etc.), which are identified either by reference to features visible on the ground or by topographical surveys that allow them to be geolocated. All this information is transcribed into SWDE's geographic information system (GIS).
23. Why have all these pipes not already been systematically replaced? - Why not draw up a specific plan for the urgent replacement of asbestos cement pipes? - What is your plan to replace these pipes in the coming years? How many km will you be replacing over the next 5 years?
There is no need to plan a systematic replacement of asbestos cement pipes rather than any other materials, as no scientific study has been able to demonstrate that oral ingestion of asbestos fibres in drinking water would have an impact on health, a conclusion which is confirmed by the World Health Organization (WHO).
In general, asbestos cement is insensitive to internal corrosion and stray current corrosion.
SWDE’s pipe replacement strategy incorporates the “asbestos” parameter. SWDE uses a multi-criteria tool to define renewal priorities, taking into account the nature of the pipes and their age. SWDE invests €100 million each year in the renewal of its infrastructure, of which more than €60 million is spent on pipes.
24. What are asbestos cement pipes replaced with?
The new main pipes laid in the networks are usually made of ductile cast iron and PVC, and more rarely of electro-weldable polyethylene or steel.
25. What measures does SWDE take to deal with asbestos work sites?
SWDE has an aggressive and consistent policy to protect its workers when working with asbestos. It has strict and safe working practices in place when cutting asbestos cement pipes. On the basis of internal procedures and operating methods, it provides staff with annual training in asbestos-related risks, as well as a manual reminding them of the precautions to be taken with regard to the workers and people living in the immediate vicinity of the site during interventions, as well as a kit of single-use personal protective equipment.
In addition, SWDE also informs its subcontractors through the Health and Safety Prevention Plan (HSPP) attached to the specifications governing the contracts. It also provides training sessions on asbestos risks and precautions.
Finally, SWDE’s internal department for prevention and protection in the workplace (SIPPT) and managers carry out site visits throughout the year, during which a predefined list of safety points are checked. The use of the "asbestos kit" is a recurring point in the rating, which is followed as an objective for its intervention teams.
26. Are customers in the vicinity of an asbestos site warned?
The measures taken on the sites to avoid the projection of asbestos fibres into the surrounding air, such as the use of slow saws and spraying continuously with water during cutting, as well as the location in a trench, sheltered from the wind, do not require the local residents to be informed.
On the other hand, sites of this type must be notified to the relevant Regional Directorate for Workplace Welfare Control (FPS Employment, Labour and Social Dialogue) in order to check that the legislation and, in particular, the worker protection measures are respected and correctly implemented.
27. Is it necessary to run the tap water more than usual after replacing an asbestos cement pipe?
After work has been carried out on the network, when it is brought back into service, the water engineers purge the water through the hydrants to eliminate the cloudy or coloured water that is inevitably generated by the work.
As a general rule, whatever the nature of the pipe, it is advisable to run the tap water for a few moments to eliminate any cloudy or coloured water that may have entered the connections and that has not been purged at the street level. There is no reason to do this more extensively when working on asbestos cement pipes.
28. Where does asbestos waste from your asbestos cement pipe replacement sites go?
The disposal of waste materials containing asbestos is subject to legislation that is reflected in the operating procedures applied within SWDE. From the launch of the work, the waste is packaged in specific containers with the personal protective equipment used by the personnel. They are collected by an approved firm for disposal in centres that are themselves approved for this type of waste.
29. Does SWDE take the opportunity to replace asbestos cement pipes on roadworks carried out by other road or network managers?
SWDE systematically examines the appropriateness of renewing its pipes when road managers or other underground installation contractors are carrying out works under the terms of the legislation on worksite coordination (POWALCO). However, this alone is not enough to decide to renew the pipes.
The choice is made on the basis of a multi-criteria tool that allows the decision to be made objectively, regardless of the pipe material. Particular attention is paid to construction sites where the nature of the work could weaken the asbestos cement pipes.
30. Can a municipality or the region require you to replace an asbestos cement pipe if it covers the cost?
Although the network is owned by SWDE and pipe renewals are carried out objectively using a multi-criteria prioritisation tool, there is nothing to prevent a municipality or the Region from financing a pipe replacement. However, the project can only be carried out by SWDE, in accordance with its technical specifications.
31. Why is it that asbestos fibres can sometimes be detected when sampling fire hydrants, but not at customers' taps?
Hydrants are special elements of the network. Their location in the branch of the pipe and their configuration mean that they are like small "dead ends" of stagnant water where fibres can become trapped and be released when the network is purged.
Main pipe in which water circulates continuously.
The body of the hydrant, which is automatically drained of its water (protection against freezing) when the hydrant is closed.
Location of the valve which isolates the body (without water) from the bypass and the duckfoot bend which remain under water.
and that are like small "dead ends" where fibres can become lodged and remain trapped and be released when the network is purged.
The body of the hydrant, which is automatically drained of its water (protection against freezing) when the hydrant is closed.
Location of the valve which isolates the body (without water) from the bypass and the duckfoot bend which remain under water.
and that are like small "dead ends" where fibres can become lodged and remain trapped and be released when the network is purged.