Digitisation of traffic signs is a gain for road managers and road users alike

It was and is a huge project, which ultimately means a gain for road users and road user safety. The digital overview of traffic signs in the Netherlands – most of which is now available as open data via the National Data Warehouse for Traffic Information (NDW) – means road managers and service providers can do their job better.

The quest for a digital overview of all traffic signs is certainly no sinecure, says Vincent Habers, senior ITS consultant on behalf of the Ministry of Infrastructure and Water Management. The designation code and exact location of all signs are recorded. The collected data are made available as open data via NDW. According to the agreement between the Ministry and HR Groep as implementer, at least 98 percent of the signs along and above roads must be complete, up-to-date and provided with the exact location in the database; the quality requirements are substantial, therefore.

Correct advice

There are good reasons for this: for example, only if the information is completely correct can services providers provide road users with correct up-to-date in-car information on current maximum speeds, road works warnings or navigation advice. Until recently, the combination of exact location, placement next to or over the road, precise message and scope was far from always known for many traffic signs. A lot of work has already been done. Initially, HR Groep charted out the details of national and provincial roads. The second tranche, the traffic signs of the 130 largest municipalities in the Netherlands (> 40,000 inhabitants), has since been completed. This autumn will see the third and final chapter: all signs of Dutch municipalities with fewer than 40,000 inhabitants.

Big job

HR Groep, specialist in (traffic) objects in the public space, sank its teeth into the operation. And yes, it’s been quite demanding, says Ellen Hoogeveen on behalf of HR Groep. ‘It’s indeed a big job. We’ve been working on this topic since 2016 and previously mapped out data for a number of municipalities’. But collecting, registering and updating everything nationwide demanded a lot of preliminary work, consultation and meant a search for tight definitions and codes. For example, the same significance was/will not be assigned to certain traffic signs throughout the Netherlands. Examples include (partly outdated) parking ban signs with additional panel and signs for environmental zones. Hoogeveen: ‘So we had to be speaking the same language first’.


And as far as ‘speaking the same language’ is concerned: an app is now available to enable road managers and contractors to quickly change temporarily installed road signs, in the event of road works or events, for instance. Vincent Habers: ‘Making such changes of course involves the necessary safety requirements and authorisation protocols. As a road manager, you will receive a personal code so that you can always find out who made which change at what time’.

As a result, data must remain up to date, and road managers and contractors can quickly adjust local information about maximum speeds, overtaking prohibitions, road narrowing or loading and unloading sites, among other things, if necessary. With its expertise in the field of data collection and access, the National Data Warehouse for Traffic Information (NDW) has supported the creation and validation of the database. NDW also set up a digital platform to be able to efficiently process the signs and changes and make them available.


Hoogeveen believes that the digitisation of traffic signs is in keeping with the times, especially because motorists are increasingly relying on their app/navigation. The question is therefore whether so many road signs still need to be erected along roads. Hoogeveen: ‘The expectation is that far fewer signs will be needed in the long term’. But for the time being, the digitisation task will have to be completed. According to the parties involved, as far as is known, the Netherlands will then be the first country with a complete digital overview of all traffic signs.