After several decades of disconnection between rivers and cities, some cities are rediscovering the values of rivers, particularly for goods transportation. In this context, the paper aims to apprehend how projects of waterway goods transportation development, mentioned in European and national sustainable development policies, are territorialized. The local planning processes of two river port projects on the Escaut river in the Valenciennes area are analyzed. Although both river port projects emerged in the early 2000’s, only one was carried out. Why ? Considering the concept of territorial planning system suggested by Moine (2006), we hypothesise that social representations of river ports and waterway transportation frame the city-port dialogue and the spatial planning shapes of their interface. Along the Escaut river edges, public authorities in charge of spatial planning consider the representation of waterway transportation as an economic development generator. As they have no competence regards to logistics and freight, local planning stakeholders rely on the local Industry and Trade Council to facilitate the dialogue with firms. Consequently, they have created a specific organization to build up the ports, in association with the local Industry and Trade Council. This organisation is able to design ports that fit well to the local economic activities : why and where to build a bulk handling port or a container terminal. However, this planning framework also strengthens the spatial disconnection between the city and its ports. Furthermore, the political conflicts taking place within the Valenciennes planning stakeholders influence the speed of the port projects implementation.