If there’s one thing that concerns me most about the impacts of the climate crisis in the Netherlands, it’s water. Melting ice caps and increasing sea levels mean we have to keep our dikes up to our safety standards, and increased rainfall is also threatening urban environments with flooding. On the other extreme, droughts and heatwaves make water scarce at certain times of the year, threatening nature and human health across the country.
My fears are not unfounded. In 1953, on January 31st, a storm surge in the North Sea led to roughly 10% of the Netherlands being flooded – 1836 people died, and the total cost of damage was equivalent to around €5.4 billion today. To avoid a situation like this happening again, I’ve been working for the City of Rotterdam and finding ways to make it more resilient to climate impacts.
One project in the Rotterdam Climate Adaptation Plan is to build rainwater reservoirs in key locations across the city. We see that, although average annual rainfall remains the same, rain is falling more heavily in shorter bursts of time – these days a single event can easily overload our sewer system. The reservoirs collect water from the surrounding area and store it for 24 hours before releasing it into the ground. None of it enters the sewer system.
In other instances, such as during heatwaves and droughts, we need more water. This is why we also capture water and use it for things like flushing toilets, watering plants and cleaning streets. Here, in particular, Rotterdam takes inspiration from the international community – though we have centuries of experience in holding water back, we know less about dealing with droughts.
For any climate adaptation infrastructure to succeed, however, multifunctionality is important. Grey clouds and rainy days might be defining factors of all countries that border the North Sea or Atlantic, but in the Netherlands it still only rains around 5% of the time. So the infrastructure must have some use during the dry periods, to be a worthwhile investment. The reservoirs are part of ten larger water plazas across the city. These are designed with locals in the neighbourhood, each one with its own preferences. This helps each water plaza to have a unique design, incorporating football fields, skateparks or other features such as greenhouses for growing vegetables.
Another reason why multifunctionality is important is because space is really scarce in Rotterdam. By 2050, we’re going to need 50,000 more homes to accommodate the growing population. Every square metre counts.
Urban planning is also influenced by the local citizens. Only around 40% of Rotterdam is public space, so getting access to the other 60% means including everyone – from big businesses, to small local communities. These are the people who live in the city, and we want Rotterdam to be a fun place to live as well as climate resilient. This is why holding dialogues with every neighbourhood is a vital part of our plan.
We encourage locals to use the space they have for building climate resilience into the city, and we offer subsidies and advice on the kinds of actions they can take. By encouraging people to work in their gardens, for example, we can also promote more green spaces in the city, boosting biodiversity. The message is that the more people join in, the greener Rotterdam becomes.
In the near future, there are actions we can take to stop disastrous floods from happening. Further into the future, in 100 or 200 years, it’s difficult to say. Ultimately, sea levels are rising faster than we originally anticipated. In certain instances, this can mean making difficult decisions that not everyone agrees with, but in the end we have to implement effective interventions.
To keep our city climate proof, it would be really helpful if there was a tool to help the city’s water, road, ‘Green’, urban planning and landscape design departments to design the city together, using one shared set of data and digital tools. This kind of tool is now being developed by Dutch organisations in an EU-funded project – IMPETUS, and this should really help.
Of course, our future depends not just on how well we adapt, but also on how well we mitigate against the changing climate, and just how far temperatures will be allowed to rise before we’re living in a world free from fossil fuels.