Cittadella Bridge, Alessandria, Italy

Repeated flooding along the River Tanaro confirmed the need to replace the original Cittadella Bridge dating from the Napoleonic era. During the floods of 1994, the water level rose to cover the roadway, and the piers of the bridge trapped much of the debris in the river, effectively acting as a dam. The new design, a single span raised above the flood plain, not only eliminates the possibility of such obstruction recurring but also enhances the natural flow of the river. Since traffic on the old bridge made it unsafe for pedestrians, the new bridge provides separate but structurally connected spans for pedestrian and vehicular circulation.

The 70-foot high bowstring arch carrying both spans is curved to the south in order to counterbalance the inflection of the vehicular roadbed bowing out towards the north. The weight of the pedestrian bridge on the opposite side of the arch helps to maintain the statical balance of the overall structure.

The new bridge design is integrated with the proposed reconfiguration of the adjacent Piazza Gobetti. This reformulation envisages an extension of the park land beneath the bridge and along the embankment. The 70-foot tower introduced as a focal point on the Piazza Gobetti will not only provide a view of the bridge from above but is also a vantage point from which to survey the connection from the city center through the Piazza Gobetti and across the bridge to the Cittadella itself.