Comprising 70 percent of our bodies, covering 70 percent of our earth’s surface, and providing more than 50 percent of the world’s ‘renewable’ energy, water is also the ultimate adaptor: evaporating, condensing, crystallizing, icing, melting, flowing and filling, according to its environment.

The beauty of water, and its emotional power as a latent energy force, is celebrated throughout architecture, from the rainwater-pooled Roman atriums and trickling water gardens of the Alhambra and the Taj Mahal, to feng shui-directed streams, artificial English lakes, and reflecting ponds worldwide.  From Fallingwater, Frank Lloyd Wright’s built homage to the Bear Run waterfall, to Tadao Ando’s masterful intensification of the calm and weight of water in his epic Awaji Island, water has proven a powerful muse.  Now the changing geography of the world demands a reaction to the practical issues of spreading water and shrinking landmass.  With fast-spreading biofuel plantations jostling with food crops and people for space, what is the appropriate built response for such epic change, and how and where do we build our houses?

The concept of the floating house is nothing new, but the genre just got a whole lot sexier with a raft of new technologies and forms. Koen Olthuis, a pioneer of modern floating structures, hails from waterlogged Holland. His firm Waterstudio.NL is dedicated to designing water-interactive houses using five main concepts.

• lifted – a dwelling on piles far above the highest water level.
• waterproof – resistant to the presence of water. (For example, a garage with elevated services, built of concrete and tile, will flood without damage).
• sealed – dwellings isolated with watertight doors and windows (as in a submarine).
• amphibious – houses used in dry conditions with a foundation that will float if the land floods.
• floating – the familiar floating house.

Almost one-third of Holland consists of polders, an artificial landscape of reclaimed land below sea level protected by dykes and maintained by constant pumping. Olthius says rising water levels are forcing Holland to ‘depolderise’, watering down the land available for building. Using patented foundations of foam and concrete, anchored on telescopic piers to eliminate horizontal movement and to allow interconnection for roads, gardens and housing zones, Waterstudio.NL is finalizing a 1400-strong floating settlement for a soon-to-be-flooded polder. Fishing for answers, I grilled by e-mail:

Koen, is it a houseboat?

“A houseboat is in fact a boat with a house-like unit on top. A water house is a house with a floating foundation, but with the exact same specifications as a normal house.”

Does the floating nature restrict its design?

“Everything is technically possible, but not always economically feasible. We always refer to floating oil platforms on the ocean, with many people working and living on board. If that is possible, then a floating apartment beyond the waterfront is easy.”

How do floating structures and their piers affect existing aquiferous ecosystems?

“We tell our clients about the environmental benefits of floating buildings compared to landfill projects. Landfill will permanently destroy the water life of the footprint. Floating buildings give only a shadow to the seabed. We have engineered a patent for a floating beach (http://www.dutchdocklands.com/). It has the look of a beach … but it keeps the seabed intact… we expect a new ecosystem to develop on the underside of the structure. Exciting for divers!”

What’s on the drawing board?

“We are preparing a dynamic development in which buildings can be moved during their life span. Normally a building will be demolished when its economical value is no longer in balance with the value of the land. In a floating city … a building can be moved to another part that is in balance with its value and continue functioning. This will save a lot of energy and is much more sustainable. We [will] design now a floating school which will move every 10 years to a newer part of Amsterdam.”

Floating infrastructure presents a raft of challenges and opportunities to town planners.  Stay tuned for more waterborn architectural innovation.

Trained and practiced in sustainable architecture, has moved from a sole practice specializing in architecture that “treads lightly” to a career in award-winning product design.  Sally’s products include the multi-award-winning Nest high chair, held in the Powerhouse Museum and the V&A in London, the Rainwater HOG which was named one of 2008’s Top 10 Green Building Products and recently awarded its fifth “green” award, and the O MOON outdoor light sold through Design Within Reach. Sally is a panelist on ABC TV’s New Inventors program, judges Car of the Year for Fairfax Media and Wheels magazine, and writes and lectures in Australia and the USA on innovative sustainable design and technologies.

Recently a judge of the Spark Design Awards and the TED/Lexus Living award, Sally is also developing more innovative rainwater storage systems and solar accessories for her company BeautifulUsefulGreen.