We distinguish between primary, regional and other water defenses. The primary defenses protect us from the (outside) water of the North Sea, the Wadden Sea, the IJsselmeer and the Markermeer. Regional defenses (storage basin quays) protect our polders from the water from ring canals and channels. Other defenses are all water defenses (or water retaining heights) that are not designated as primary or regional water defenses and whose standard is set by the district water board.

We make sure that our flood defenses are in good condition so that we can live safely in the lower Holland. Therefore, we set requirements for the use of the flood defenses and for the space around them. These requirements are laid down in the Water Board Ordinance.

The Register map Watersheds consists of Maps with explanatory notes. These are adopted by the board. This is a legal obligation. The Omgevingswet states that the district water board is required to "establish a register map for water works under its management, in which the work is described according to location, form, size and construction." The Maps also show the safety zones and associated structures such as pumping stations and locks. We also designate maintainers of the flood defenses in the register map .

The digital Map (green button) shows the primary and regional flood defenses. The digital Map has been adopted administratively as far as the regional flood defenses are concerned. This has not yet been done for the primary flood defenses. These are included in the laying books. The layer books have been established administratively and can be found under the link 'Downloads register maps'. In the near future we aim to adapt the digital Map also for the primary flood defenses and have it administratively established.

The Register map hardly changes. It is updated only when the location, shape or size of a dike has changed, for example after a dike reinforcement.

Register map Watersheds

Other barriers

Flood defenses for which the state or province has not established a safety standard have been designated as other flood defenses. These other flood defenses have of course also been Map , but have not yet been digitized in detail and are therefore not included in the Register map Water Defenses.

See also