Glossary Legger Waters
Dredging
The removal of excessive dredging that hinders or may hinder the discharge, supply or storage of water. This involves securing the normative supply and/or discharge of water; ensuring that the profile of waterways at least meets the required legger dimensions.
Storage area
An area designated under the Spatial Planning Act (as of January 1, 2021: under the Omgevingswet) for hydraulic purposes, not being a surface water body or part thereof, that serves to expand the storage capacity of one or more water systems and is also included as a storage area on the legger.
Protection zone
An area adjacent to a water body, in which regulations and restrictions may apply for the protection of that work, as established in the Water Board's approval.
Basic registration of large-scale topography (BGT).
The BGT is an important part of the system of basic registrations. Basic registrations enable single acquisition and multiple use. By storing the data in the BGT unambiguously, they can be reused by all government organizations that need this data. The Water Board is the source owner of the waters and flood defenses, among other things. The BGT replaces the Large Scale Base Map of the Netherlands (GBKN).
Bottom width
The width of the bottom at the bottom height to be maintained and the desired slopes.
Bottom Height
The required ground elevation relative to NAP, which in combination with the water level established in the water level decision determines the minimum required water depth for the supply and/or discharge of water.
Extraordinary maintenance
Conservation of waters in accordance with the direction, shape, size and construction stipulated in the legger.
Category
A classification of waters based on the surface area of territory to be supplied and/or drained and/or based on the storage function. Three categories of systems are distinguished, namely primary, secondary and tertiary.
Just maintenance dry
The proper maintenance of the banks and embankments as well as the corresponding bank defense works, insofar as this is necessary to prevent the drainage, supply or storage of water from being obstructed by subsidence or washout, or constructed maintenance strips or fences from being threatened by subsidence. For slope maintenance, it may be necessary to raise the collapsed slope out of the water. Removal of vegetation and overhanging branches.
Just maintenance wet
Cleaning and mowing the wet profile of the water to the water's edge, by removing vegetation and materials from the water. For waters wider than 6 meters and located in the secondary system, maintenance of the riparian zone up to 3 meters into the water belongs to the ordinary maintenance dry.
Insertion height
The elevation at the intersection of the sloping bank embankment (bank slope) with horizontal ground level. Expressed as height relative to the bottom of the ditch (depth relative to ground level) or relative to NAP.
Hydrovak / hydro-object
Division of a surface water body according to equal and homogeneous characteristics distinguished within it.
Artwork
Civil engineering work for the infrastructure of roads, water, railroad tracks, water defenses and/or pipelines not intended for permanent human habitation.
Artwork subject
A hydro section consisting (almost) entirely of a structure. Dimensions and maintenance obligation are recorded with the structure.
Ground level
Elevation of the ground surface in an area, excluding slopes and berms or other (artificial) elevations or decreases;
Maintenance obligation
The manner in which liability for maintenance of surface water bodies, storage areas and engineering structures is defined in the legger. Who is responsible (maintenance obligation) for carrying out (or having carried out) which maintenance activities (maintenance obligation).
Maintainer
Natural or legal person responsible for the maintenance of water works. Maintenance obligation The liability for maintenance of water works managed by the Water Board, as specified in the legger or in regulations accompanying exemptions.
Surface water body
Cohesive whole of water occurring freely at the earth's surface, with the substances contained therein, as well as the associated soil, banks and, insofar as expressly designated under the Water Act, drier riparian areas, as well as flora and fauna.
Level regulating structure
Artwork for regulating water levels.
Level separating structures
Artwork for separating two different water levels.
Primary system
System of waters important for the supply and discharge of water and water storage at regional and polder levels.
Profile
An imaginary intersection of a surface water body, shown schematically. To be divided into a dry and wet part, separated by the water table.
Pseudovak
A hydrovak that serves only to connect with other hydrovakes. Dimensions and maintenance obligation are defined in the adjacent hydrovak.
Secondary system
System of waters important for the supply and discharge of water and water storage at plot level. Waters that are not part of the primary system are part of the secondary system unless they are designated in the legger as part of the tertiary system.
Embankment
The lateral boundary between water bottom and ground level (the sloping plane). The slope of the embankment is expressed as a height relative to the mooring width. The location of the
left or right slope is determined by viewing the cross-sectional profile of the surface water body downstream.
Tertiary system
System of waters whose main function is water storage. Waters may be part of the tertiary system if they are not of major importance for supply/discharge.
Water depth
Vertical distance between water level and water bottom.
Waterfront / waterfront
The boundary line between water and shore.
Water level / waterline
The interface between water and air.
Watershed
Surface water body, storage area, water barrier, supporting structure