In the Netherlands, many authorities have something to say about water:
The government provides general regulations regarding drinking water. Such as the drinking water law and decree. These concern the quality and security of supply of tap water. The government is also the supervisor.
Water boards are responsible for regional waters. They must ensure that the surface water is of good quality.
The province is responsible for the quantity and quality of groundwater. They also determine how much groundwater can be pumped where.
Municipalities are responsible for protecting the drinking water supply. They must ensure that activities in public spaces do not pose a risk.
Drinking water companies must comply with the Drinking Water Act. They are obliged to supply good quality water.