In recent weeks there has been much attention on the amount of lead in our tap water. Among others, an increased concentration of lead was found at six elementary schools in Utrecht and a childcare center in Groningen. Intake of too much lead has a negative impact on brain development, so this discovery is particularly important at child care centers so that the right measures can be taken. Many are wondering how this could have happened in Dutch tap water and how serious the consequences are.
What's in our tap water?
Dutch tap water is of very good quality. But what does good quality really mean? The answer is not very simple, but basically it means that water doesn't make you sick and that it contains minerals that you need naturally. So that means that good water contains more than just H2O. It is then just not easy to determine which minerals are good or bad: the concentration determines the toxicity.
Dutch tap water is checked daily for 65 parameters to see if they fall within the set standards. Exceedances of this standard are thus quickly noticed and remedied. The standards have been drawn up as concentrations that are safe to ingest throughout one's life, which means that a single exceedance is not immediately a health risk. Only in a serious case is tap water banned from consumption, as in the case of the Vlaarding E. Coli contamination in 2017.
Hoe kan er jarenlang teveel lood in het water zitten?
The tap water company has the responsibility for water quality up to a building's connection. This means that the quality can deteriorate unnoticed after the water meter, for example due to stagnant water or lukewarm temperatures. Legionella is a well-known example of a bacterium that grows in home water pipes, for example during vacations. The pipe material itself also affects water quality, as small amounts of the pipe material are released into the water. Safe materials, such as copper or plastic, have been used to make water pipes since 1960.
However, older buildings may still have lead pipes, causing excessive concentrations in the water. You can check what the pipes look like at the water meter. In some cases, such as the child care center in Groningen, there was still a piece of lead pipe in the building despite a renovation. Therefore, if in doubt, it is better to have the water from the tap examined. Incidentally, even in buildings with new pipes and/or taps, exceedances of the standard can occur. The advice is therefore to run the water for at least two minutes daily for the first three months before the first use of the day.
One of the most troublesome contaminants in water supplies is biofilm. If you want to read more about this, this blog is highly recommended.
Legionella control also has some challenges, you can read more about that here.
At Watter, we work to disinfect water safely. You can read more about our approach here.