St. Croix River Crossing
Stillwater, MN
Much of the boundary between Minnesota and Wisconsin is provided by the St. Croix River, a National Wild and Scenic River. Over the years a number of concepts have been proposed for a new crossing of the St. Croix at Stillwater, but none succeeded until 2009, when the current concept was approved by an Act of Congress. The approved bridge is an extradosed bridge. It allows long spans, minimizing the number of piers in the river, but with shorter towers than a cable stayed bridge.
The rounded forms of the piers and girders are based on natural precedents: the reeds that line the river. The open vertical slits in the towers and their thin tapered legs minimize their visual presence. The bridge will appear delicate and transparent, resting lightly in the landscape. Low-key aesthetic lighting will ensure that the bridge is just visible in the nighttime landscape.