Heat stress test in municipality of Apeldoorn
In 2014, several heat maps (pdf, 6.7 MB) were made for the municipality of Apeldoorn. The heat stress maps visualise the locations at which temperatures will rise on hot days and can be used to identify problem locations. Subsequently, measures can be devised for such locations to anticipate aspects such as health, the environment, and sustainable energy. In many cases, solutions can offer synergy advantages to combat waterlogging and to open up opportunities to enhance the liveability of a city.
Proper interpretation of heat maps is important if such maps serve to underpin a municipal plan of action. For example, it is important to be aware of the uncertainties in the underlying model and how these can be taken into consideration. This project was aimed at ensuring proper interpretation of the heat maps by drawing up summaries and explanatory notes.
Heat stress test set-up
To substantiate the “analysis” component of the heat theme, a heat map has been developed on the basis of a heat model. Tauw has created the model and the municipality has supplied the required data.
In addition, the vulnerable groups and locations have been identified. Subsequently, the data has been combined and the main bottlenecks have been identified.
Results
In Apeldoorn, higher (perceived) temperatures tend to concentrate in the city centre and on industrial estates. Heat stress on an industrial estate will push up the use of air conditioning systems and could result in (even) fewer employees going outside during their breaks. In many cities, industrial estates are areas that heat up significantly during hot spells. An appropriate measure can be to embark on greening roofs, in collaboration with the businesses. Another option could be the construction of green belts with trees to line cycle tracks and footpaths, where employees can abide during their breaks. This will also enhance commuter traffic routes.
The city centre is a key hotspot in both the ambient and perceived temperature map and the distance-to-cool map. This is the case in many municipalities. Solutions may include green roofs and strategically situated green belts. In terms of sensitive locations, we see that a particularly large proportion of homes and schools are situated in “warmer” or “much warmer” areas. Many homes will have air conditioning; in such cases, heat will not pose a major health risk. However, in the purview of the energy transition, it is important to consider how the area surrounding such homes can be greened and how the premises themselves can be enhanced by improved insulation or green or white roofs. This will also add to the comfort of residents. Furthermore, the proximity of (well accessible) greenery is particularly important for this group of people. Many schools are accommodated in low, flat-roofed buildings which heat up rapidly. This will adversely affect the performance and health of the children during heatwaves. In such cases, greening the schoolyard, improving the insulation of schools, and the construction of a white or green roof (whether or not including solar panels) could provide a solution.
Potential measures
Temperatures are rising, and in the future heat will pose a greater problem in the Netherlands. Cities would be wise to already incorporate the combat of heat stress into their strategies. Several measures can be taken to combat heat stress. These can be divided into:
- Adaptations to public space;
- Adaptations to or within buildings;
- Raising awareness.
In terms of adaptations to public space, a particularly effective measure is planting trees to provide shade. In addition, water in the city also has a cooling effect, particularly during the daytime. It is wise to have the creation of green and blue facilities in the city tie in with existing green and blue structures. As for adaptations to buildings, the main measure will involve proper insulation. Green or white roofs may also have a significant cooling effect. Raising awareness is another important step. For example, proper ventilation during the night is an effective measure.
Lessons to be learned from the project
An explicit translation of the heat stress maps into what they entail for a municipality is a crucial step. Such a translation has been set down in a report. Based on the distance-to-cool map, heat maps, and vulnerable groups, a number of locations have been identified at which the heat problem could be most pressing.
This project was carried out in 2017; this year, the municipality of Apeldoorn participated in the regional stress tests. The results are available on www.klimaatvalleienveluwe.nl.
Contact person
Diederik Anema
Gemeente Apeldoorn
d.anema@apeldoorn.nl