Flooding of inhabited areas is one of the major, but often neglected, challenges that await future generations. It is a problem that needs to be addressed rapidly to help prevent unnecessary loss of lives and unforetold economic damage. But instead of fearing and fighting water, some argue we should develop our cities in a way that makes use of it, and take a non-defensive approach towards rising water levels.

A range of futuristic floating city concepts has already been proposed as unconventional ways to use water, but they may not become a reality anytime soon. In the meantime, we should look at integrating water into the long-term designs for existing cities, for example in the form of interconnected waterways, deepwater ports and buildings that can be flooded. Floating solar and wind farms and tidal power generation off nearby shores could also be integrated.

By making use of the water that surrounds many of our cities, these concepts may offer more benefits than reactive measures such a flood defences and sandbags ever could.

London-based Baca Architects have re-imagined how one of the most flood-prone cities in the world could be protected as it grows in to a mega-city. Their proposals for Shanghai are outlined in a new book, Aquatecture, which is due out next year. It looks a different ways of designing for water, picking up on practical examples from around the world. The book complements the firm’s specialist work around designing waterfronts and water architecture, which includes amphibious houses.

A serious threat

From January to early December 2012 floods accounted for 54% of deaths in Asia, according to the United Nations. In China alone, more than 17 million people were affected by flooding and $4.8bn of economic damage was caused.

Also in 2012, researchers from the University of Leeds, writing in the journal Natural Hazards, said that Shanghai is the most vulnerable majority city in the world to suffer from serious flooding. The researchers found that Shanghai and Dhaka would remain the most vulnerable major cities up to the 2100s – although the potential for flooding would increase in all cities.

“It is not just about your exposure to flooding, but the effect it actually has on communities and business and how much a major flood disrupts economic activity,” said Professor Nigel Wright, who led the research team.

Building a flood-resilient city

Shanghai’s history is deeply connected with the surrounding water; the Yangtze river has helped it grown in to one of the biggest economic powers not only China but in the entire world. The downside is that the city is prone to flooding and is one of the cities most likely to see a serious detrimental impact from rising sea-levels in coming years.

But Baca Architects believe that the impacts of flooding can be minimised by thinking about how the city is developed at present. In 2011, China announced six satellite towns would be built around the city, and it is likely with population growth over coming years that they could eventually be connected to the surrounding provinces.

The architects argue that the location by the river allows for the new towns to be connected in different ways. “Between the satellites, high-risk areas are used for industry with the waterways providing economic routes for heavy goods transportation to the rest of the city and the deepwater ports,” they say. “Off shore floating solar farms, designed to move with the waves, are linked to high-altitude wind generators as well as energy producing tidal barrages to create a distributed and interconnected renewable energy system.”

Their concept is based on four key principles: a resilient system, city rotation, water utilisation and transitional zones – all based on the levels of the land and what its potential uses are.

Resilience can be achieved by the individual satellite towns working together to address any weakness in the overall system, for example, if a power connection fails. As sea levels rise, the architects envision the fabric of the city being reconfigured, or rotated, to use different areas. This may mean that land that is submerged at one point could be used for agriculture if water levels in the area drop; they could also become industrial areas or waterways with a change in tide.

Utilisation turns the threat of water into an opportunity. Land for freshwater storage is preserved within satellite towns for future times when low-lying areas are lost. Transitional zones may be used for water harvesting and water treatment and could also be used for future developments in line with changing water levels.

This approach, the architects argue, could help create a city that does not get damaged by floods but can be flexible to the challenges created by rising water levels.

Living with water

Baca Architects’s re-imagining of Shanghai and the individual water projects they are working on, which will allow flood protection and water use at an individual level, stem from the main ideas behind the LifE project.

This study, which was funded by the UK Government, looked to change the way we think about living with water and concluded that we should take a non-defensive approach to flood risk management.

Water should be allowed onto urban sites, in a pre-determined manner, and not be completely blocked off, the architects argue. Responsible developments could reduce the risk of flooding and also utilise renewable technologies. This idea led them to develop a range of buildings that look to work with water, not against it.

The amphibious house

The large-scale proposals for Shanghai show how a whole city could be transformed to accommodate water, but on a localised level there is also potential to develop technologies that allow individual homes to adapt to changes in the environment.

Areas of low-lying land, or land close to rivers, are always prone to flooding. Baca’s amphibious house is designed to reduce the impact of floods when they happen. It is built on a dock that rests on fixed foundations but can rise up with the water level and float, coping with up to 2.5m of flood water. To allow the house to float the upper levels are made of a lightweight timber construction that rests on the concrete hull.

The house has been designed to be future-proof to projected water levels in the Buckinghamshire area of the UK.

Baca director Richard Coutts says that those living in flood-prone areas need houses that help to protect them and their belongings. “It is not only their homes but also their communities that need to be designed to take this into account so that the consequences can be mitigated,” he adds. “Amphibious design is one of a host of solutions that can enable residents to live safely and to adapt to the challenges of climate change.”

The surroundings of the amphibious house have been designed to act as an early defence system to flooding. Terraces created on different levels will flood first, preventing the house from being hit by a flood wave all at once.

The home that floods

In a more radical approach, Baca Architects are working with Aquobex Resilient Property on a building that can be flooded completely if water levels rise.

The Aquobox, due to be built at the BRE Innovation Park in Watford, UK, is a demonstration home that will be set in a tank and flooded on a daily basis to show how far flood resistant technology has progressed. Aquobox features a fully floadable kitchen as well as water-resistant nano-coatings, fire and flood-resistant boarding, automatic flood guards and water-resistant cavity wall insulation.

The nano-coatings are similar to those being developed to help clumsy smartphone and tablet users protect their gadgets from liquids. But Baca and Aquobex Resilient Property believe they could also be used to help protect homes from damage during floods.

Looking at the bigger picture

Elsewhere, architects, designers and engineers are also looking at new ways to counter an age-old problem.

In New York, almost $1bn has been awarded to a number of infrastructure projects to create flood defences around New York City and New Jersey. The projects, which came out of a design competition earlier this year, include a which will double up as a park and public space. It is intended to run more than two miles along the river and effectively raise the riverbank to nine feet above its current level.

But while these projects use the more conventional technique of keeping water out of individual areas of a city, the concepts outlined by Baca Architects are taking a view of the bigger picture. They incorporate the development of new technology as well as considering the sociological factors of food production, travel and growing populations.

Their approach takes into account in all the factors a city needs adapt to in order to deal with future environmental issues that lie outside our control. It is how we, as a society, should be looking to protect our living spaces for future generations.

Aquatecture by Baca Architects will be published by RIBA Publishing, early 2015.

Featured image and images four and five courtesy of Baca Architects. Image one via chinahbzyg / Shutterstock.com