Ny : gestion intégrée de la plaine de Naives

Ny & the Naives river are located on the basin of the Ourthe, major tributary of the Meuse. It is a good example of how to combine flood prevention, adaptation to climate change, ecological conservation, agriculture & tourism.

Ny has a high architectural value but is regularly flooded (1/year, 3 times in 2007). To solve the problem, new channels will be installed & the flow accelerated. Discharges outside of Ny may damage downstream urban and agricultural areas & infrastructures, so there will be created a controlled natural water retention zone of 10 hectare.  But the waters of the Naives are in poor quality due to an old sewage system.

Such a complex problem requires an integrated management of the sub-catchment; that will be done in 3 steps.

A.      not within AMICE

B.      The wooded banks in the Natura 2000 plain will be cleaned-out and managed with the participation of local citizens. Faster evacuation at this point will worsen floods downstream of the village. It is impossible to solve floodings in Ny without a durable and collective management of the catchment of the Naives and its wide alluvial Natura 2000 plain.</p>

C.     The Natura 2000 zone downstream of the village will be flooded during high waters. It requires the improvement of water quality (quality issue not within AMICE project). The Walloon Region will also monitor the flora and fauna on the Natura 2000 area.

D.     not within AMICE

The Natura 2000 zone can buffer more or less 10m³/s during a flood. The maximum discharge recorded at the connection between Naives and Ourthe was 224m³/s. The town of Hotton was completely under water. The maximum flood admitted is 160m³/s. If, for example, the Ny project can be reproduced on seven more river basins, we can have a new approach to flood management of the Ourthe river. Moreover, the increased urbanization of the Ourthe valley reduces the options and management of the smaller rivers may be the only sound solution.

The local population has been contacted at the very beginning of the sub-project: help-desk, contacts with experts, maps presented, etc. They are directly involved for the works being carried out around their houses. The aim was to improve the value of houses and the water quality, inform about biodiversity, low emission transports and sustainable development.

The AMICE project is highly taking into account the wishes of the local farmers in order to maintain the agriculture on the area in correlation with the aims of Natura 2000. All information about the AMICE project is available for all Partners as well as the public.

Thanks to AMICE, communication will reach a wider level and include climate change, which will reinforce the understanding of the works being done.

Many operators are associated to the reflexion:

- the Province of Luxembourg (inventory of the Naives stream, water quality, flora)

- the Walloon Division of Nature & Forests: responsible for the Natura 2000 area