Rhine - Ontpoldering Noordwaard
Rhine - Ontpoldering Noordwaard
The Noordwaard is part of the Biesbosch. The Biesbosch has a turbulent history, with many changes by man, water and nature. The area used to be an estuary, but in the Middle Ages it was a large polder for agriculture. The Saint-Elizabeth flood in 1421 turned the polder into a large lake. Later, natural processes developed the Biesbosch again into an estuary. In the 1885, the Nieuwe Merwede was constructed to regulate the discharge in the area and in the 20th century, the entire Biesbosch was again a polder but with large parts of the original creeks remaining. Since the 90s nature development has given parts of the area back to nature and it is now an important nature and recreation area. The influence of the tides was lost with the construction of the Deltaworks, but the Biesbosch still has a high ecological value. The Noordwaard has a large network of creeks caused by the flow dynamics and sediment transport by the tides.
The Noordwaard was selected to serve as a flood retention area in the Room for the River program, a national program to adapt the current flood defense structure to future climate change. In this project, agricultural land is given back to the river to improve the discharge during flooding and the nature is allowed to develop.
Pressures and Drivers
Agriculture has played a large part in the current look of the area. In the past land has been reclaimed and turned into small polders which were later connected. The river lost its connection with the floodplain by the embankments which protect the polders. Now, recreation also puts pressure on the system. The Biesbosch is a popular area for boating and the increasing number of recreationists damage and disturb habitats.
The project has two global objectives, namely:
- Create more intertidal nature that is connected to the existing Natura 2000 area Biesbosch
- Decrease normative high water level at Gorinchem with 30 cm and keep local houses protected
The project only has a specific objective for flood protection. The normative high water level at Gorinchem has to be reduced with 30 cm.
The success criteria is a reduction of the normative high water level at Gorinchem with 30cm
A map from 1905 is used as reference for the development of the area. The embankments of a large number of polders are lowered to create an area which will flood during winter. Two clusters of small polders remain protected by high embankments. Houses outside the new dike rings will be adapted to flooding. Historical creeks are restored, but in some cases are closed off to prevent recreation. Nature is allowed to develop, but only on the edges of the discharge zone. The rest of the zone remains empty with grasslands that can be used for grazing in summer. Recreation is concentrated in two recreation zones on the west and east side of the area to reduce recreational pressure in the discharge area and the creeks.
No information about pre- or post-restoration monitoring could be found in the project documents.
Expectations and Response
It is expected that the measures will have a positive effect on the ecological value of the Noordwaard and the Biesbosch as well as improvement of the flood protection. There are more possibilities for recreation, but the concentration of these activities will not disturb the local communities in the polder clusters. Agriculture will lose a large share of land in the Noordwaard from 1750 to 600 ha. To keep the livelihood of farmers sustainable small scale recreational side activities are allowed.
Project Ontpoldering Noordwaard is lead by Rijkswaterstaat, in cooperation with:
- Ministerie van Infrastructuur en Milieu
- Ministerie van Economische Zaken, Landbouw en Innovatie
- Provincie Noord-Brabant
- Waterschap Rivierenland
- Gemeente Werkendam
- Combinatie Noordwaard (group of companies involved in implementation)
During the planning phase, an advisory board with members of all relevant stakeholder groups was set up and the project plans were discussed. The project is currently in the implementation phase. The stakeholders and general public is informed via a website with a contact form, information meetings twice per month, project news letters and a special phone number that can be called when a calamity occurs for direct contact with the contractor (Combinatie Noordwaard).
The exact project budget could not be found in the available documents. The project is part of the Room for the River program which has a budget of 2.180 million Euro.
Name: Cees Vervoorn
Phone-Number: 0031 183 - 72 46 00
Bureau Noordwaard (2006) Ontwerpvisie Ontpoldering Noordwaard
- Improve water retention
- Increase flood frequency and duration in riparian zones or floodplains
- Link flood reduction with ecological restoration
- Improve backwaters
- Lower river banks or floodplains to enlarge inundation and flooding
- Reconnect backwaters and wetlands
- Remove hard engineering structures that impede lateral connectivity
- Retain floodwater