There’s no doubt the world’s climate is changing and this is not only leading to more severe floods, but the kinds of floods we’re seeing are changing too. It’s well documented that climate change is causing an increase in extreme weather, such as hurricanes, and these can cause absolute devastation, but there are other new and less obvious types of flooding. Rivers can get blocked by melting ice flows, glacial lakes melt without warning, heavy rainfall causes deadly mudslides to wipe out entire villages and sea level rise is putting coastal communities, including some of the world’s major cities, at risk of becoming untenable.
Too often flooding hits the world’s most vulnerable people, destroying their homes and livelihoods and leaving those left behind without access to drinking water or other basic services. But take a look at floods in Germany, China and New York this year and it’s obvious major flooding is seriously disrupting some of the world’s wealthiest societies as well.
The breadth of the problem means that flooding experts have to think about how to help a huge variety of different communities with different needs and, sadly, different budgets. But we are getting there.
Solutions are coming from what might seem to be diametrically opposed places. The first is to use the latest technology and techniques, including imagery from space, to predict where, when and how flooding will happen, which we call ’flood forecasting’. The second is to manage the problem by working with nature, which we call ‘nature-based solutions’.
Both are a very long way from the days when the solution to flooding was to build big concrete structures in an effort try and hold back the waters. In this new climate, the problem is just too widespread for hard engineering solutions alone. In fact, sometimes they can even make the problem worse for others who are not protected by concrete walls and are often just too expensive. That’s not to say that big engineering isn’t useful in certain scenarios – the Thames Barrier springs to mind – but a major shift in the industry is to helping communities to live with flooding and to place more of an emphasis on looking after our precious natural systems.
There is also the issue of education. Many communities are facing flooding for the first time and have little idea how to protect themselves. Here at HR Wallingford, we liken flooding to fire in the last century. Back then very few people had a smoke alarm in their houses, whereas now it would be unthinkable to be without one. Granted, that’s a very western perspective, but there are plenty of things that communities across the globe can do to prepare themselves for what is going to be a very rough ride in the centuries to come.
There will be more about education later, but for now let’s return to flood forecasting and nature-based solutions. What are they and how can they help?