Ecohydrology: what the Netherlands is doing to mitigate flood and drought risk

Climate change means that not just temperatures but weather patterns in general are altering, and we’re also likely to see more extremes: storms that are stronger and more frequent; dry spells that are more protracted. And this means we need to plan ahead and mitigate accordingly. Which inevitably means better water stewardship. But, as he explains to Chris Smith, the point Ruud Bartholomeus, from the Netherlands KWR Water Research Institute, makes is that there’s not a one size fits all solution, because the challenges of flooding are quite different from the challenges posed by droughts; so we need to anticipate the different threats and work with the environment making long-term investments…

Ruud - With the droughts emerging from 2018 onwards, we faced a new challenge. Even in countries like the Netherlands where we have a water surplus, we had to deal with severe droughts during summer periods and we had droughts in the decades before, but they often had during only one year. But this was different now we had a multi-year drought and also given the climate projections for the future climates, it was clear that we need to anticipate within our water management to prepare and to guarantee sufficient freshwater also during summer periods in the future. But anticipating on drought seems to be much more difficult. We were questioning why it's so difficult to cope with droughts too and how we can guarantee sufficient fresh water for the future.

Chris - Is it just because, hitherto, in a country like the Netherlands, the main challenge has been water surplus; droughts have been infrequent, so it hasn't really focused people's minds? Or is it that the challenges of coping with a drought are so different from coping with water surplus that it takes a totally different way of thinking and that takes time to evolve?

Ruud - First of all, the impact of floods on people is, and on the environment is a lot different than the impact of droughts. Water surplus and flooding comes fast but it disappears fast. But the impact is very large. People can die from it. It's a lot of damage to infrastructure; it's very visible. While the impact of drought, it's comes slowly. A lot happens below ground. Normally people don't die of it, so it's much less visible. It's completely different from anticipating on flooding. Regarding the measures that need to be taken, partly they are different, but they are also to some extent quite similar. When we look to the flood defense in the Netherlands after the floods of 1995, we came with a new programme where much more space was given to the rivers so that we can deal with these kind of extreme rainfall events and extreme discharges. Dealing with drought also asks for organising land management so that we can have the precipitation surplus from winter that we can save for summer periods.

Chris - Do you think to an extent that because in the past we've tended to do what we wanted to do and then change the environment to accommodate our wishes, we're gonna have to flip this round a bit and start saying, well, this is what the environment's going to do, so we have to adapt our land use more accordingly. And that might not always sit comfortably with what our priorities are, but it's going to become a priority?

Ruud - Yes, I agree that that's needed and that's also why the national government of the Netherlands introduced policy on water and soil as leading forces adapt to what the environment facilitates to do with your environmental use and not try to put everything to what you think that should be present at a certain place. So make the environment more leading to activities that you can plan. That is quite difficult of course, because you have many functions in place already, but you can think of that changing a function at a location is very difficult, especially in a country like the Netherlands, which is a small country. Many functions are integrated close to each other and that's one of the main challenges that we have to face. And that's also why it's not possible to have simple solutions to the drought problem. It's not, we take measures and within four years everything is solved. Now this is really into a transformation of the water system and completely different thinking of how we deal with our land also in relation to water, but water is more leading in, in the environmental planning and the environmental use.

Chris - So what do you think then should be on a policymaker's priority list?

Ruud - Within our paper we investigated or identified the success of different transitions that we made within the Netherlands, especially focusing on prevention of flooding. So we had a clear vision from the national government how things needed to change. Room for the river is the same. It's not a policy of four year, it's a long-term vision on how we want to deal with flood protection in the future. If you have this long-term vision and this societal acceptance that we want to achieve that vision that's one of the main goals and it's very important to achieve these goals. The same we need to do also for drought. We don't need to look at short-term solutions, but we need to have this long-term vision and find the adaptation pathways to reach that new situation where we find this new balance between water surplus, water demand and water system management.