River expansion + City park

Room for the River Nijmegen

This is the most complex project within the Room for the River programme. In addition to water management measures such as the creation of a bypass channel with inlets, dike lengthening and nature development, this unique project involved the construction of three new bridges. Moreover, in the center of the river, an inhabited island is created.

© Hans van der Meer

Motive

The Waal river makes a sharp bend near Nijmegen and narrows at this point, forming a bottleneck. By moving the dike at Lent 350 metres inland, room is created for a bypass channel which drains the water during extremely high water levels. This feature will offer better flood protection near Nijmegen.

The design is based on the river water dynamics and the erosion and sedimentation process

The river park forms the highlight of Nijmegen’s new flood protection for the Waal river. The design is based on the river water dynamics, the erosion and sedimentation process and the tides. The Urban River Park is freely accessible and respectfully integrates archeological and historical elements into the design. The innovative park design enables the space to be usilised in different ways, including the hosting of events and exhibitions on the new island.

Approach

Intervention in the heart of the city

By constructing a bypass channel, an elongated island is created in the river Waal, between the historic centre and the new Waalsprong district. The island and bypass channel together form a river park, that offers a combination of water and nature, recreation and urban activities.

Before
After

Coordination role and landscape design

H+N+S Landscape Architects was the coordinating architect for the i-Lent contracting consortium and was also responsible for the landscape design. The Nijmegen council’s preliminary design was fully developed into a final design for the Urban River Park and its various elements. The coordinating architect from the council was included in the management team in order to integrate and realise the vision.

Design plan

Result

Layered planning map

The urban development plan consists of three elements: creating, growing and water movement. The layer ‘creating’ represents the physical elements that are built, constructed, dug or raised in the construction phase. The second layer, ‘growing’, shows how the landscape may develop after implementation of the Room for the River Waal project. The third layer, 'water movement', details the fluctuation of the water level throughout the seasons. The paths situated on different elevations are designed to accommodate for the water level fluctuations.

Connected landscape

The underlying landscape determines how the architectural objects in the plan are embedded in the surroundings. The urban development plan consists of a detailed architectural image which optimises the natural shape of the banks. The plan is developed in collaboration with civil, construction, hydrology and ecological engineers and architects.

The threshold

The 'threshold' is the most important hydrological precondition for the effective functioning of the bypass. It has an assymetric design with a stone covering on the upstream side and a smooth finish on the side of the bypass. The tubes in the threshold ensure sufficient water renewal and water flow in the bypass.

The bridges

The Citadel bridge, designed by NEXT Architects, connects the events ground on the Veur-Lent island with the northern banks of the Waal river. Together with the connectors, the Citadel bridge forms a route that can be flooded in the event of high water levels. The Promenade bridge, designed by Ney-Poulissen Architects & Engineering, is the formal route from the urban quay to the Veur-Lent island. The banks are designed to accomodate for the land abutments of the bridge and there are routes above and underneath the bridge.

Section Citadel bridge

The quay

The design of the quay, the Lentse Warande, involved consideration of materials, technical details and the design of the sitting edges, the parapet and other urban furniture. The quay is embedded in the surrounding river landscape and the slipway reflects the sturdy and urban character of the quay.

Flooding of the inlet © Hans van der Meer

Winter 2018 : Spiegelwaal in action

During the weekend of 6 and 7 Januari, the population of Nijmegen emerges to enjoy the high water levels in the urban river park. The sun reflects on the giant body of water, providing a spectacular view. The Citadel bridge can only be reached by the stepping stones, that were implemented for this exact reason, and provides a playful attraction with the occurrence for many visitors. On Sunday in the afternoon, the entire path on the threshold also begins to overflow. The water levels keep rising for several days but the additional water storage by the Spiegelwaal ensures a safe course of the exceptional high water levels.