A water retaining facility comprises:
- a dam;
- the associated reservoir;
- safety-relevant auxiliary installations.
Dams may take the following form:
- concrete or masonry dams;
- embankment dams;
- river impoundments with their side embankments.
A reservoir is a lake that is artificially formed by dams.
The reservoir volume is the volume of water in a water retaining facility that could be released in the event of a total collapse of the dam when the reservoir is full.
The storage height of a water retaining facility is the height of water impounded by the highest dam when the reservoir is full.
Safety-relevant auxiliary installations are structures and equipment installed on the reservoir and dam that are required for the safe operation of a water retaining facility, in particular relief and outlet works.
The operator of a water retaining facility is the holder of the licence to put the facility into operation.