update IMGeo 2.0

The final consultation date for IMGeo (including BGT) is announced. This is August 29 with the consultation period which will last three weeks. The websites of Geonovum and IenM will announce the way the consultation will be carried out.

Review on the BGT informationmodel

seen on the VROM website

On wednesday september 15th and thursday september 16th the Ministry of Housing, Spatial Planning and the Environment will present the draft informationmodel of the Large Scale Basemap (BGT). Until september 29th there is time to review and give feedback on the draft.

Geonovum requests input for IMGeo v2.0

seen on the Geonovum website

Geonovum invites you to contribute to the next version of the large scale basemapping informationmodel IMGeo.

IMGeo includes the obligatory BGT specs and in addition a set of optional specs. The new version of IMGeo, version 2.0, is all about these optional specs and will include “plus-topography” and “maintenance-topographyā€¯.

Again involved in a BGT project

Besides the BGT-project in Limburg, what has evolved from Pilot into Production fase, I’m involved in a couple of other projects where the BGT is an important component.

In existing geo-information systems, DWG is often used as format for large scale basemaps. For other processes in the organisation DWG’s have to be converted into Shape- or SDF-files. We are currently executing a research how to store and use this data from a central geo-database and we would like the structure to be BGT-ready.
More posts about this topic soon.

BGT-boundary, a pragmatic approach

I’ve written a couple of posts about the BGT-project which I’m working on lately. A recurrent topic, when speaking about the BGT, is: “where should the border polygon be situated ?

Frist suggestion is the cadastral border. This is also an authentic registration and a good solution for two municiplalities. I’m involved with a project at one of the provinces and they “slice” through municipalities with their provincial roads, that makes the cadastral border less useful.

AutoCAD Map - existing GBK-data in DWGUsers of the provincial map are among others the departments of road- and greenmanagement. Besides surveying the topography, that is situated in a corridor along the road, the road- and greenobjects are important for these maintenance maps. Sometimes there is more green managed than is owned by the province – imagine a ditch that is mown completely, while the cadastral borderline is in the center of the ditch. Currently many road crossings are tranferred into roundabouts, and therefore the province needs to buy pieces of land from municipalities or private owners. The new cadastral situation will take some time to become established and therefore the cadastral border isn’t up-to-date.

AutoCAD Map - new BGT-data from Oracle Spatial with on top existing GBK-data in DWGIn our project we’ve taken a pragmatic approach: we use the outside topographic lines in the corridor maps to build the polygons. In some cases we have to add supporting-lines to close the polygons. If the BGT border polygon has been defined than we will know which polygons needs to be splitted. The current maintenance and cadastral borders are left out of the proces for now. Also buildings, fences, roadlines that a partly on the map, but outside the provincial maintenance area are left out of polygon creation.

With this approach we can create the object oriented map and use the geometry of road- and greenobjects to connect to maintenance-data.
In the meantime still discussing with the GBKN Foundation, municipalities, waterboards, National Road Administration and the Ministry of Housing, Spatial Planning and the Environment about the BGT border polygon.