Kampenhout: Measuring air quality and traffic at the school gate
You tackle the following challenges:
Introduction
Suppose your municipality is groaning under the rush hour traffic to and from the big city. As a local government, you look for solutions, but how do you use air quality as a parameter? VITO (Flemish Institute for Technological Research) and the municipality of Kampenhout took the test. Together they set up a measurement project at the local school gate. Afterwards they came up with a blueprint that you too can use. A conversation with Martine Van Poppel (VITO) and Elke Delbare (Regional intermunicipal association Haviland / Municipality of Kampenhout).
In Kampenhout in Flemish Brabant, many cars pass every day on their way to Brussels. The cut-through traffic has been causing chaos and dangerous situations at Parkschool Relst for years. And what about the air quality there? The municipality developed test setups to deal with traffic flows and saw air quality as an important argument for making a policy choice. This is specialist work, so VITO wanted to support the municipality of Kampenhout within the City of Things project, financed by VLAIO, the Agency for Innovation & Entrepreneurship. The result of the pilot project is a blueprint, a useful step-by-step plan for any local government that wants to get started with measurements to support policy choices.
Workshops
Martine: 'VITO, together with the Board of Innovation, organized a workshop for ten cities and municipalities to let them find out why they wanted to set up a sensor network and what it should look like. We did see the concern about air quality, but at the same time it was not clear to them what steps they had to take to use measurements in policy. We eventually involved Kampenhout and Sint-Niklaas in two model studies: how can you set up a sensor network? How do you analyze the data? What do you communicate to your residents? Three other municipalities - Dilbeek, Schoten and Oudenaarde - were also closely involved in the whole project.'
“We wanted to demonstrate how a sensor network can support policy, rather than comparing policy options. After all, air quality is only one factor that is in the balance.”
- Martine Van Poppel, VITO
Meanwhile in Kampenhout
The situation at Parkschool Relst caused enough nuisance to test some traffic interventions, they thought in Kampenhout. The municipality monitored the impact of two different measures on traffic volume and, together with VITO, registered the air quality. For this purpose, VITO placed sensors in three different places.
The measurement project took place in the spring of 2021 and lasted approximately three and a half months, during which 4 situations were examined: the normal traffic situation, school holidays, and the two traffic measures.
'Our question to VITO was threefold,' explains Elke. 'First of all, we wanted to know which sensors we could best use. We ended up choosing a cheaper and a more expensive type. For fine dust, for example, it turned out that the cheapest sensor worked best.'
“Second,” she continues, “we wondered what parameters to monitor. For example, it turned out that we already had a good idea of the effects of the traffic measures on the basis of nitrogen measurements. Particulate matter appears to be less suitable for this purpose, because that concentration also depends on other factors such as renovations, industry or even Sahara sand. The particulate matter peaks that are due to traffic can be filtered out less efficiently.
'Rolling out measurements is not that easy for a small municipality,' concludes Elke. 'It is not the case that you quickly buy sensors, plug them into the socket, and that's it. You already have to count on a consultancy or VITO that professionally carries out a calibration, analyzes the data and then interprets it correctly.
Martine: 'Policy choices are of course up to the municipality. At VITO, we translate the measurement results into an understandable story and help the municipality to calculate the precise effect of their measures. For us, the aim was to demonstrate how a sensor network can support policy, rather than juxtaposing policy options. After all, air quality is only one factor in the balance.'
Cut or school street?
Elke explains exactly which traffic measures the city council has tried. 'We experimented for a while with a cut in the street of Parkschool Relst. For example, we made through traffic impossible at certain hours and always in one specific driving direction: in the morning towards Brussels, in the evening towards Leuven. The effect in the afternoon was rather limited: the evening rush has not really started yet. The measurements clearly showed that there was much less traffic passing the school gate in the morning.'
'In the next phase we opted for a school street: when the school opens and closes, the street is completely car-free. This obviously had a clear effect on air quality. But another problem immediately arose, because car drivers parked their cars around the corner and thus hindered cyclists and pedestrians. The situation was unsafe and, moreover, difficult to handle because a lot of volunteers are needed to direct the traffic.'
That is why Kampenhout finally decided to stop using certain parking spaces around the school at the beginning and end of the school day. The traffic situation immediately improved considerably. Through traffic is still possible, so the air quality remains the same. 'The practical problems at the school street were actually much greater than the profit we could make,' says Elke. 'It also turned out that the air quality at the school was in order. As an argument to change things, that did not hold much weight. And of course that's just good news (laughs).'
blueprint
VITO and the VMM worked on a blueprint to help other, especially smaller cities or municipalities. 'In this way, the boards know how the process is going and which tools and agencies can offer help,' explains Martine. 'Local authorities don't always have the knowledge in-house and it is almost impossible to interpret your data on your own and then link the correct conclusions to it. The scenario was developed on the basis of a literature study and the pilot studies, from which we have drawn up a concrete step-by-step plan. With our study we also showed that sensors can help to underpin a good air quality policy, if you choose the appropriate method. You can also find these results as a scientific article in the journal Atmosphere , by the way.'
“Measurements make it possible to draw objective conclusions. They will give you all the information you need to make the right policy choice in the short term.”
- Elke Delbare, Kampenhout
Watch and learn: tips and experiences from VITO and Kampenhout
- Think before you start : 'Don't just measure,' says Martine, 'but think about what you are doing it for. What do you want to achieve in your municipality? What possible interventions can you test? Sensors and their quality is one thing, but how, where and for how long you install them is just as important. Anyone can measure, but sometimes it still happens too much at random. The blueprint helps to manage that.'
- To measure is to know: 'Measurements make it possible to draw objective conclusions,' says Elke. 'And if you want, you can also make changes. We have measured the air quality in various situations and decided not to do anything drastic based on that, but things could just as well have gone differently if the measurement results were worse. It gives you all the information you need to make the right decision in the short term. As a board, you should not be afraid to communicate to citizens that the air quality is bad. On the contrary: you test a number of setups and you effectively improve the situation based on the measurement results.'
- Dare to ask: Martine: 'Make sure you involve people with knowledge, because there is a lot to consider when analyzing your measurement results. As VITO we are happy to guide you and the VMM also carries out air measurements.'
WHO IS?
Martine Van Poppel – VITO project manager for the City of Things project.
Elke Delbare – Environmental expert at the regional intermunicipal company Haviland and, 2 days a week, can be found at the environmental department of Kampenhout.
