The European Commission has opened infringement proceedings against Belgium for failing to comply with the EU drinking directive across all three regions and at a federal level, the commission announced on Thursday.
The shortcomings concern the quality of risk assessments carried out by national authorities for private distribution installations, the monitoring of drinking water quality and the mandatory information that must be provided to the public.
Belgium has been formally called on to address these issues within two months.
If the response is deemed insufficient, the case may be referred to the European Court of Justice.
The EU drinking water directive forms part of the union's "zero pollution" ambition.
It targets polluants such as endocrine disruptors and microplastics and introduces rules designed to ensure cleaner tap water.
It also aims to reduce leakage rates, with around 30% of potable water in the EU currently lost during distribution.
Member states were required to transpose the directive by 12 January 2023.
