Case study: Room for the river (part one)

Room for the river view

In 2006 the Dutch Cabinet proposed the Spatial Planning Key Decision (SPKD). The SPKD is a design plan for more highly innovated structures and the modification of existing structures in the immediate floodplain site. Meander Consultancy and Research Partners contributed to the site analysis and interpretation. The project was active from 2006 to 2015.

The Room for the River project site encompasses four rivers: the Rhine, the Meuse, the Waal, and the IJssel. The project area is in the Netherlands, but morphological impacts extend upstream into Germany, portions of France and Belgium, and may reach to the Rhine headwaters in Switzerland over time.

The design presents an integrated spatial plan with the main objectives of flood protection, master landscaping and the improvement of overall environmental conditions. Completion of a basic package of forty projects is foreseen for 2015, with a budget of €2.2 billion.

Nijmegen part plan

The goal of this project is to improve safety against flooding of riverine areas of the Rivers Rhine, Meuse, Waal, IJssel and Lek by accommodating a discharge capacity of 16.000m 3/s. Also, contributing to the improvement of the spatial quality of the riverine area or we can say to add a spatial quality to the area around the rivers, reconnecting our country to the rivers.

Here is some strategies for room for the river project.

1.Relocation of dykes

Dikes will be relocated farther from the river shore. This will create additional space within the flood plain for the river during annual floods.

2.Lower the level of floodplain

In addition to the relocation of the dykes, the floodplain bottom will be lowered in depth. Increasing the depth in the floodplain must occur due to the collection of sediments in the area after years of regular flooding.

3.Reduce height of the groans

The groans within the riverbed will be lowered to allow for more drainage to occur during an increase in water levels more quickly than presently positioned. Groins will be added in specified locations in addition to the modifications occurring to the existing structures.

4.Construction of a “Green Channel”

A “Green Channel” will be constructed serving as a flood bypass around Veessen-Wapenveld.

5.Increase the depth of the side channels

Side channels will be lowered in depth to increase the barrier between the river and infrastructures and residents. It will also allow for more water to be removed from the flooded location thus reducing the breach of the dikes.

6.Removal of obstacles

Locations along the river where there are obstacles will be addressed. For example, the hydraulic bridge at Oosterbaan will be removed. Removing or modifying obstacles in the river wherever possible helps increase the flow rate for the river water.

What I learned from this project is that building dams is not the only way to deal with floods. When we use land, reclamation based on more river channel space, we may find a way to dredge the river as opposed to “blocking”, while creating more green space and public space for the city. However, when it comes to California, we have to considerate the reality of building land at sea, such as having to avoid wetlands.