The Approach of Traffic Modelling in Noord-Brabant (Netherlands)
Martijn Heynickx, Provincie Noord-Brabant, Rogier Koopal, Goudappel Coffeng
How does Noord-Brabant position itself in the modelling process and keep track on model developments? The BBMA is our answer: a strong partnership, a solid system and techniques to provide reliable information for spatial and mobility policy.
The province of Noord Brabant is a regional government with civilian duties, such as spatial planning, environmental policy and of course policy towards mobility and infrastructure. Traffic modelling is one of our main instruments to supply our policy with the valuable decision-making information it needs. Because of the impact on decision making, we need it to be as consistent as possible.
There are 3 levels of (road) traffic models in use in the Netherlands: national, regional and local. Because of growing discrepancy between the national and local/regional insights and needs, the number of local models increased over the past years. Those low-scale models didn’t answer regional issues and lacked mutual synchronisation. Between 2003 and 2006 regional models emerged, but they lacked synchronisation as well. Both in input and techniques and thus in results.
Therefore, the province started the BBMA (BrabantBrede ModelAanpak – Modelling Approach All of Brabant) in 2012, together with its national and local partners. The major goal was to increase their effectiveness and to minimize the risks towards infrastructural projects. Primary steps to achieve this ambitious goal towards the traffic models in Noord-Brabant were:
- increasing the quality of input, techniques and thus output;
- creating transparency and synchronisation in input and following results;
- creating a partnership with important stakeholders.
Through this partnership we provided an overall vision for the entire province. This partnership consists of 66 local governments (municipals), the province of Noord-Brabant, the ministry of infrastructure & environment and several consultancy and research institutes. An important forum is the workgroup BBMA, consisting of the province, representatives of all regions and the ministry.
To achieve the envisioned increase in quality, transparency and synchronisation, we needed a solid basis for the input. A relational database was fed with all the necessary data a traffic model needs. By choosing the lowest level of data availability (88.000 areas in the province, 140.000 links), there is no limit to the aggregation level you need. And most important: all data used in this database, is the same input for every region or city.
Using the same, consistent input is important, but does not guarantee the same results. Techniques are important as well. Demand modelling is done using the same technique and set of parameters throughout the entire province. By using the matrices of the national models (as well as the parameters) as a start for our base model, we created a link with the models of the ministry.
Another new and complicating factor was adding a complete multimodal approach in all of our regional traffic models. Bike and public transport are hereby added as full-fledged modalities in the estimation and assignment results.
To ensure a similar matrix structure between the models, we have used a rudimentary ‘master-matrix’ on a provincial level with 3.300 areas. Regional models are ‘refinements’ of this ‘master matrix’. This way the same input is used for the same cities across different models.
Thanks to the intense cooperation with all the important stakeholders and the technical improvements, we have achieved our goals: more consistent, the development of traffic models has become a solid process, we know which input and techniques we used and why, … But foremost, all governments have the same vision of the future of Noord-Brabant!
Association for European Transport