Climate change science is clear: we are looking at very real sea level increases, and more frequent extreme floods. Unfortunately, an inconvenient number of cities are rather closer to the water than their residents would prefer. What ideas are out there to meet the challenge?
There are, if one strips the various proposed solutions down to bare essentials, two main schools of thought:
- Stop the water
- Go with the flow
The first is obviously a necessity in some cases; historic buildings such as London’s Westminster Abbey are precious cultural resources. They are going to have to be protected in place, without changing the aesthetics of the original structure. To achieve this there are, again, 2 options. Soft engineering solutions, typically the restoration of natural barriers such as sand dunes or mangroves, are a popular choice but require time to establish, and space generally has to be cleared. It’s still viable in some cases: Governor Cuomo of New York recently proposed actions to reduce coastal flood risks, including the buy out of some 10,000 homes, which will then be razed to allow the land to serve as a flood buffer.
Hard engineering is typically limited to flood barriers- either literal walls or more innovative designs such as the one already found on the Thames. Worryingly, the projected end of useful life of the Thames Barrier was recently revised from 2070 to 2030 due to accelerated sea level rise.
The second approach, working with the water, is gaining in popularity and producing some rather futuristic and very exciting ideas. Stilts are old favourites, and still popular in certain regions, but Koen Olthius, founder of Netherlands based Water Studio, has taken a new approach. His designs for floating buildings scale up from individual homes to entire Olympic stadiums, capable of being transported from host city to host city –provided, presumably, that the host city has a convenient area of aquaspace nearby. This would certainly prove a boon for stretched budgets, and potentially greener games, while also making sea level rise a non-issue.
NLÈ, an architecture firm split between Nigeria and the Netherlands, has just completed a sturdy, triple storey floating school for Makoko, a shantytown built precariously, house by house, on the coastal waters off Lagos; the school will provide a working, reproducible model for replacing the rest of the dangerous and unsanitary housing of the area.
In the UK, BACA architects have broken ground on London’s first aquatic house on the banks of the Thames; the design features a buoyant basement modelled on already inhabited buildings in the Netherlands. At normal water levels, the house in at ground level, but in flood conditions, it is perfectly capable of rising with the water. The design, if successful, could mean a transformation of the Thames’ commuter belt, and was featured in a Culture Show special on March 13th, available in the UK for a limited time here.
While it seems alarmist to suggest that no city near water is safe, the existing record of water vs. buildings isn’t exactly encouraging; in the US alone, we have the contrasting examples of Hurricanes Sandy and Katrina; the former battering a city without any real flood defences, and the other, even more worryingly, wrecking havoc on a city that did.
Given that the American Society of Civil Engineers’ 2009 Infrastructure Report Card awarded the US a D-grade for things such as bridges, dams, levees, and inland waterways, with an upgrade estimate of $2.2 trillion over five years, there’s a lot of work to be done, and plenty of impetus for more innovative designers to come forward.