Pilot Investment Dynamic Beekdal
(River Aa) in The Netherlands
Waterschap Aa en Maas, Internet: www.aaenmaas.nl
Project manager: René de Louw; E-mail: rdelouw@aaenmaas.nl
The River Aa is located in the South of The Netherlands. During the first part of the last century dikes along the river Aa were constructed to prevent flooding of the farmland located on the floodplain. The water management vision “Dynamic River Basin” envisages removing dikes along the River Aa and to reconnect the river with the natural floodplain and to restore the system again. This solution offers possibilities for different functions of the river basin in an integral approach
The first 0.5 km of the “Dynamic River Basin” Project was included as a pilot investment in the nofdp Project. This section refers to the Meander Assendelft near Middelrode.
- Here the original 550 m length of the Aa is transformed into a meander with a total length of 770 m.
- The old river bed is filled with sand taken from the project area in order to improve the environmental conditions for the desired nature target types.
- In the old situation the river had a summer bed which was 20 m broad and was deepened up to 2.20 m in the past. Now, the new bed of River Aa is 0.9m deep only.
- 8 ha of wetland was created, which is going to be inundated once every year. This area is a ecological connection zone between the wildlife areas “De Wamberg” and “Het Wijboschbroek”.
- At a lower frequency of once every 10 years the inundated area will increase to 10 ha.
- In extreme situations, once in a 100 years, 12 ha will be flooded. In such a situation 100.000 m3 of water will be stored in this part of the floodplain.
The Waterschap Aa en Maas is implementing this pilot investment in close cooperation with the Province of Noord-Brabant and the city councils of Sint-Michielsgestel and Bernheze. The implementation of the pilot investment started in 2008 and will be completed in early 2009. The costs were about €1 million including land acquisition.
In order to implement the "Dynamic River Basin" Project land from 17 farms is required. Therefore, the Waterschap Aa en Maas is using a legal instrument for realising water storage areas. This instrument was jointly developed by all waterschaps of the Province of Noord Brabant and includes the application of the following fundamental principles:
- any water storage area is a well defined part of the floodplain, which needs a long and intense participation procedure with land owners, waterschap and the municipality;
- the water storage area has to be laid down in the local land use plan;
- its function and technical information has to be laid down in the technical archives of the waterschap;
- the realisation of the water storage can only be done when there are juridical agreements with the land owners.
When the waterboard is intending to use agricultural land or nature for water storage, the owner can apply for compensation of the damage in two ways:
- the disadvantage compensation regulation and
- a private inundation damage compensation agreement.
The main points of this private agreement are:
- The waterschap will compensate for inundation and floating rubbish.
- The compensation is associated with a predefined amount of money related to the kind of crop, the inundated area, the inundation period, the fertilisation used, management costs and the state of the crop at the time of damage. They are based on known standards for crops in The Netherlands.
- The amount of money for compensation is also dependent on measures the owner himself could take at the flooding event.
- The owner has to notify the damage to the waterboard.
- The agreements are reached on a voluntary basis.
These regulations will be incorporated in the new Dutch Water legislation.
