Bridges don’t have to arch upwards

Rethinking the basics of the bridge

Everybody knows what a bridge is – it provides a traverse between two points, spanning something else. After multiple thousands of years of human ingenuity and engineering innovation, what can be new about the fundamentals of bridge design?

The Moses Bridge in Halsteren in the Netherlands, designed by RO&AD architecten, provides an eloquent answer, with a remarkable rethink of what’s possible. This pedestrian bridge actually lies below the surface of the water it traverses to provide access to an early-17th century Dutch fort. The designers met the need for a discreet, unobtrusive solution by building a ”sunken” bridge that follows the line of the fort slope and is almost flush with both the rampart and the level of the water, making it practically invisible to anyone approaching the fort.

Moses Bridge delves down

Mastering materials

Not surprisingly, this isn’t just a good design idea – most good design and architecture features an interplay with materials. The Moses Bridge features the innovative use of Accoya wood The Accoya® process involves sustainably grown timber undergoing a nontoxic acetylated wood modification that allegedly results in a product capable of matching or exceeding the durability, stability and beauty of the best tropical hardwoods. This key capability makes it possible to immerse the structure of the bridge – or is it a walkway? – in the water.

Walking under water

Winner of an ArchDaily Building of the Year award in 2011, the Moses Bridge (parting the Red Sea – geddit?) is much more than just one more clever bridge design. It is a complete rethink of where a bridge can be placed in relation to the other spatial elements of a site and of the landscape as a whole. It provides a dramatic new spatial interaction between the walkway and the water, and the whole landscape. Instead of balancing above what it traverses, this bridge is within and below – a remarkable rethink.