The 12th January 2021 is the date and Member States will have two years to transpose it into national legislation.
The revised Drinking Water Directive will modernise the 20 year old drinking water directive (98/83/EC) comes as a result of the REFIT evaluation, the implementation of the Commission’s response to the European Citizens’ Initiative ‘Right2Water’ and as a contribution to meeting the targets of the Sustainable Development Goals.
Here there is the document