Whether you believe in global warming or not, it has been proven that there has been a rise in rainfall in the Northeast, Midwest, and upper Great Plains region of over 30 percent compared to pre-1960 levels. This means the communities need to adapt their infrastructure to accommodate the excess rainfall. Thankfully, they are not just adapting, but also using it to their advantage.
As cities grow up and out, there are more impermeable surfaces to obstruct the natural runoff of the water. Singapore is a great example of a city that has already adapted. They use advanced drainage infrastructure to collect and recycle water. They also have sensors that monitor toe water levels in real time. Norfolk, Virginia was awarded a grant last year of $120 million to implement underground cisterns, permeable pavers, create urban forests and riverfront wetland areas, and upgrade storm drains. Berlin saw its heaviest rainfall this summer in a century and they took advantage of this by using green spaces with deep soil and swale trenches to make the city a “sponge” . As the water evaporates, it also cools the urban environment!
As well as making overall cities, better planned to accept the rainfall, individual buildings are adapting. Backflow valves in plumbing and drainage systems and elevated podiums for parking spaces are all helping to save millions of dollars in damage.
Green roofs are very popular (as you may know), but there is another solution I believe to be even better: blue roofs. These are like plastic sponges that retain water on flat roofs. It then has a system that harvests the rain for landscaping and irrigation while relieving pressure on drainage infrastructure. These are also two to three times cheaper per square foot than green roofs.
I look forward to seeing more cities working together with developers to take advantage of the rainfall rather than have it as a hindrance on the city.