Sea levels are rising globally; climate change is causing the temperature to increase, which melts ice sheets and glaciers. Satellite radar revealed that between 1993 and 2017, the sea rose by 7.5 cm, and the ice caps melting melt is accelerating.
Rise in Sea Level
Scientists at the Intergovernmental Panel on Climate Change (IPCC) estimate a rise of 90 cm by 2099 – meaning some areas of the world are at risk of disappearing entirely over the next few decades.
Cities have been tiptoeing into the water ever since we started building harbors; to tackle the urban pressures of population density and climate change some countries are reclaiming land to build much needed homes. For example, Singapore has increased in size by 22% by building into surrounding waters using sand, earth and rock which has been quarried or purchased elsewhere.
However, there are other ways to combat this threat; rather than build on land, architects are now designing homes, and indeed whole towns, that can float.
Living on the water is nothing new: narrowboats, barges and houseboats provide a floating domiciliary for many; residents of the Tonle Sap freshwater lake in Cambodia live in floating houses; and the Uros people of Lake Titicaca in Peru live on floating islands made of reeds.
Architects are taking the idea of amphibious living to a whole new level, unlocking redundant waterways by building on ‘blue space’ sites such as manmade docks, canals and marinas. Floating houses could offer a real solution to easing the housing crisis and help reduce the inner-city overcrowding by providing practical, affordable spaces capable of dealing with floods and rising water levels by simply adjusting to the swell of water.
The idea has been successfully applied in the Netherlands where more than 50% of the country is either at or below sea level. IJburg is an interconnected series of artificial islands on IL lake, linked to mainland Amsterdam by bridge. It was designed to deal with the city’s critical housing shortage, and its vulnerability to flooding. It features a mix of expensive condos and social housing, shops, schools and public spaces – but is by no means finished; once complete it aims to offer 18,000 homes for 45,000 people, as well as 12,000 jobs.
A little further north-east in Copenhagen, Denmark, architecture firm Urban Rigger have created floating accommodation for students from end of life shipping containers. Each has 12 studio apartments and a shared courtyard with a barbeque area, bike racks and a kayak store. The homes are tethered to the docks in the city, and are partially solar powered. The success of the Danish sites led to the company pledging to build a further 1,000 to 1,500 container-based homes in harbour, canal and river intensive cities across Europe in the next decade.
However building on water is not easy. Take for example the Makoko Floating School in Lagos; built to provide a school and community centre to a floating slum in the city, it collapsed following heavy rainfall. Safety is a big issue, but so is the effect these houses might have on the environment.
When building floating homes, foundations still need to go deep into the river bed, which could alter its composition and lead to silt erosion and deposition elsewhere in the river, a phenomenon already observed at bridge piers. It could also alter the flow of the river and disrupt transport routes.
However, foundations can also create good anchor points for plants and help foster biodiversity and create habitats for fish and birds. Indeed, an underwater drone survey in the Netherlands revealed sites at ILburg provided a dynamic and diverse aquatic habitat.
Furthermore, such blue cities can also be an excellent means of reusing old shipping containers and other existing infrastructure. This enables them to be easily adaptable and to change their function or even location when necessary. Communities on water can also be constructed more densely allowing them to make better use of energy. One architect suggests that blue cities could even open up in the summer to collect the sun’s energy, and huddle in the winter to keep warm and preserve energy.
It seems that floating houses able to rise with flooding or swells of water could be the next big thing, and their potential to make use of old infrastructure and to conserve and generate energy currently outweighs any environmental concerns.
References and Further Reading