Development in Cadastral Surveying and Mapping in the Netherlands

Kadaster’s History, Cadastral Map and Surveyor Field Reports

The Netherlands’ Cadastre, Land Registry and Mapping Agency (Kadaster for short) provides legal certainty about the ownership status of each piece of land in the Netherlands – the cadastral parcels. All the land parcels in the whole country had been created in the years prior to the beginnings of the Kadaster in 1832. The original field sketches, however, are in most cases not available anymore. The focus was on getting the cadastral map at scale and not on archiving the field sketches for boundary reconstruction purposes. The surveyors had to pay for their own paper, ink and measuring equipment, and often considered the sketches made in the field as their private property. Today most of the cadastral surveyors are Kadaster employees.

From that moment on new boundaries were measured accurately by surveyors when parcels needed to be altered (split or merged) and recorded in field sketches. These sketches form the basis of the boundaries in the cadastral map and are also used to reconstruct boundaries in the land upon request.

Unfortunately they did not store these documents in a central register until 1878, so valuable information about the exact location of the early boundaries has been lost, which makes the reconstruction of such boundaries difficult and not very accurate. Hence, since 1878, the fieldwork archive has been kept systematically and provided with a uniform layout.

The cadastral map provides a visualization of the (relative) location and shape of all cadastral parcels in the Netherlands. Such an image of 100% land coverage that is seamless throughout is very useful for a whole range of applications. However, the graphic quality of the boundaries in the cadastral map renders this map unsuitable for accurate measurements in the map. Initially the cadastral map was a collection of individual plans on paper. This means that mapping was done directly on paper and at scale (1:1000/1:2000), with consequences for accuracy.

The results of this process were fit for the purpose of the mapping, i.e. area calculation for land taxation. Only later was the cadastre also used to provide legal certainty.

Legal & Technical Foundation

Kadaster has a legally negative system which means on the one hand that the Kadaster cannot guarantee the quality of the stored and presented data, but on the other hand does everything to make the quality and reliability of the data as high as possible. Zevenbergen and Ploeger [4] provide more information about the legal aspects of cadastral systems, including the Dutch one. A central aspect of this system is the will of the landowners themselves. When a parcel is split into two or more new parcels, new borders have to be established. For each new border, the neighbours on both sides must agree on the definition of this new border. They do this by giving clear information to a Kadaster employee, who will measure everything necessary for later reconstruction and describe this accurately in field reports and the cadastral map. This new boundary is called the “cadastral boundary” and is the cadastral interpretation of the intention of the owners with this particular boundary. This intended boundary can be interpreted as a legal boundary at that particular moment; only a judge can come with reasons to change the location of a cadastral boundary when he or she thinks that the “real” (legal) boundary should be somewhere else at a later moment. When neighbours later come up with suggestions for new locations, this leads to the land being split into new parcels and new borders being defined instead of the borders being changed.

Figure 1.

The technical foundation of cadastral surveying and mapping in the Netherlands can be found in the so called “Handleiding voor de Technische Werkzaamheden van het Kadaster” (HTW; in English, “Manual for the Technical Activities of the Cadastre”). Four versions of this manual exist: 1902, 1938, 1956, and 1996. The content is both scientific and practical, and is a reliable framework for developing work processes and quality control. The mathematical geodesy methods for adjustment and testing, as developed by the Delft University of Technology and referred to as the “Delft school of Mathematical Geodesy”, is the basic concept.

Field Sketches and Cadastral Map

As mentioned, the field sketches have been archived since 1878. Today all field sketches are scanned nationwide and accessible to Cadaster staff (for the public, only upon request and the paying of a fee). An important function of the field sketches is their use in the reconstruction of cadastral boundaries in case of disputes between neighbours about the location of their common parcel boundary. An example of a field sketch is provided in Figure 1. In most cases the sketch was originally made by hand. The sketch has no strict scale, as the scale is variable and is related to the information density required and observed in the field. Cadastral observations can be based on measurements with tapes, total stations, GNSS, etc. Observations describe the relation between the boundary and its environment, for example corners of buildings. Via the consequent use of GNSS in almost all the projects for the last 20 years, the connection to the national coordinate system (Rijksdriehoeksmeting or RD) can be made. The measurements and observations in the field sketch are documented digitally and made digitally accessible.

The field sketch includes the name of the cadastral municipality, the cadastral section letter and the cadastral parcel IDs of the parcels involved in the subdivision. The date of the survey is included and references to earlier field sketches related to boundaries of the parcel(s) involved, and observations as foot point of a survey line, distances, ‘perpendicular’, ‘parallel’, ‘extensions’, ‘straight line’, etc. The field sketch visualizes which points or lines establish the boundary.

Boundary reconstructions by cadastral surveyors based on field sketches with original observations regarding the disputed boundary, are mostly accepted by both owners, but in case of continued disagreement between the owners they can go to the court for a final decision. The layout of the field sketch has changed over time – and looks much more formal today than the example from 1957 shown in Figure 2.

Figure 2.

The cadastral map was fully digitized by 1994, and the usability of the map was substantially improved after harmonisation with the large-scale topographic map and the connection of all the individual map sheets in a period of ten years after that moment.

Nevertheless, the graphical quality of the represented boundaries in the cadastral map makes this map unsuitable for accurate measurements in the map. The standard deviation of boundary points in the map is 20 cm for urban areas and 40 cm for rural areas. This is why the documented observations from the field sketches, and not the map as such, are used for boundary reconstructions. However, the cadastral map is accessible as a seamless nationwide map and comprises the graphical representation of about 8 million cadastral parcels and parcel identifiers, together with main buildings and addresses for orientation. An excerpt of the cadastral map of the Netherlands is shown in Figure 3.

Figure 3.

Production of the Reconstruction Map

In order to create a reconstruction map, all of the measurement data from the fieldwork reports need to be extracted, measurement data from different fieldwork reports have to be linked to each other, and the entire network has to be calculated. Then, the current boundaries will have to be identified from the lines, which include the historical boundaries and buildings as well. For this purpose, the current cadastral map serves as a reference. In Figure 4 these steps are explained in more detail. The big challenge is investigating whether significant automation of the necessary manual processes is possible when reading scanned analogue fieldwork reports and calculating the data from the fieldwork reports in relation to each other. For these calculations, software that allows for a complete automatic quality check and description will be used.

Figure 4.

The first two steps of the process are described in more detail in Franken et al. [3]. There, the tooling developed for the digitization of the field sketches and the interactive environment for validation and coupling is discussed. In all four steps, quality assurance is applied and integrated in the tooling. The approach adopted is the Delft school of Mathematical Geodesy and is described in more detail in van den Heuvel et al. [2]. The renewal process comprises the following four steps:

Figure 5.

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