holesovice-karlin footbridge competition, 2017

Prague is a city rich in history, and flooding. This single span mediates the juxtaposition of new development, a repurposed precinct, and a soon-to-be refurbished island. Public plazas buttress each end of a connecting pathway with links to island trails via sloping helical flood resistant ramps. Midway, the deck populated with benches, widens into a viewing a platform. Floating above river and island alike, a cable-stayed asymmetrical structure is coupled with a robust concrete frame at its required connection below flood plain.  Much like the spires soaring above this medieval urban fabric, a new iconic mast prominently situated at island’s end, punctuates the skyline of this more modern precinct of a great river city.

A narrow north embankment, flood levels, waterway flow and management, and island access suggest limited solutions. Inspired by migrating cranes, a lightweight structure takes flight. A vertical mast supports an arcing walkway: narrower at its abutments, the bridge widens to accommodate connecting ramps to the island below. Bridges should be about more than just getting from one side to the other. Similar to other bridges in Prague that are enriched by their street life, at mid-span, the full width of this one can be experienced by pedestrians and street performers alike, offering ample space to linger, to make place. 

Rising safely above flood level, this solution is really three bridges in one.  Allied with two new context appropriate public plazas, for the first time two urban neighborhoods now directly connected, readily share access to the new life of an island landscape over this elegant iconic footbridge.

The bridge is conceived as a synthesis of two systems: A lighter asymmetrical cabled-stayed structure spans the 300 meter width of the river, mostly above the 2002 flood plain.  Where the bridge is required to drop below flood level to connect to the island , cast in place concrete provides a durable frame, specifically designed not to impede water flow. Tying the mast to this frame along with bracing against the deck, reduces the lateral overturning forces generated by the tension in the stays.