Stretching from the high plateaus of the Ardennes to the Meuse with an elevation drop of nearly 600 meters, the Ourthe valley is at a crossroads facing the climate emergency and demographic mutations.
A documented systemic rupture
Wallonia sees its artificialized land represent about 16% of its surface. In the Ourthe valley, the steep topography accentuates land competition. Projections forecast a household growth of +14.0% by mid-century, requiring the creation of about 7,000 additional housing units per year at the regional level.
"Dredging, once considered a panacea, is today formally identified as ecologically damaging. The future lies in soft methods like brush clearing."
In the 19th century, a massive project planned to canalize 300 kilometers of river with 205 locks to connect Liège to Wasserbillig. Today, the approach is radically reversed. The 2023-2025 Action Program of the Ourthe River Contract (CRO) deploys 814 actions, including 506 led by municipalities.
The University of Namur and the CRO use a 3D augmented reality sandbox (EXACT LAB project) to allow local stakeholders to instantly visualize runoff dynamics and infrastructure exposure issues during floods.
🏗️ Engineering & Redevelopment
The Strategic Plan (SSIGVH 2050) provides €13.4 million for the renovation of this critical flow regulation infrastructure.
An estimated budget of €16.5 million is allocated for the installation of next-generation fish passes on the Meuse and the Ourthe.
Restoration of fragile environments: limestone grasslands in Calestienne and securing of karst networks sheltering bat populations (horseshoe bats).
Land acquisition to replace spruce monocultures with native deciduous forests, thereby increasing the soil's water retention capacity.
The development of the RAVeL includes environmentally friendly structures, such as the footbridge between Comblain-la-Tour and Fairon, assembled entirely by hand in a Natura 2000 zone.
📸 Photographs of the territory
Concrete projects serving resilience: from dam renovation to the restoration of deciduous forests.
🔄 Tourism and tomorrow's development
| Field | ❌ Historical Model | ✅ 2050 Vision |
|---|---|---|
| River management | Systematic dredging, mechanical extraction | Brush clearing, principle of "making room for water" |
| Spatial tourism | Sprawl, leisure parks of the 70s-80s | Redevelopment of existing "tourist brownfields" |
| Forestry | Massive planting of conifers (spruce) | Natural regeneration of deciduous forests |
| Local mobility | Structural dependence on cars | Shared lanes (advisory bike lanes), park-and-ride (P+R) |
| Example of an urban hub (Barvaux) | Dense and mineralized urban fabric | €18M urban renewal, redevelopment of riverbanks |
🌿 European Natural Heritage
Two European LIFE projects, acting in synergy on the basin's varied geologies, are shaping the valley's ecological future by 2050.
This project restores rare thermophilic environments (limestone grasslands, beech forests) from Rendeux to Hamoir, and secures the Esneux-Tilff karst network — hibernation habitat for the Greater horseshoe bat and Geoffroy's bat.
Plots of coniferous monocultures (Natura 2000 code 9180*) are bought, logged one last time, and then returned to nature. The native deciduous forests that regenerate have a higher water retention capacity, naturally skimming Ourthe floods.
The PNDO structures its governance around distinct landscape entities: Saint-Hubert high forest plateaus, upper Ourthe marshy bottoms, Aisne wooded terraces. Local perception has evolved: reopening the valley bottoms is now seen as an economic and ecological necessity.
🚲 Mobility & Territorial Governance
The Liège–Hamoir stretch is completed, including the Comblain-la-Tour/Fairon footbridge, assembled entirely by hand in a Natura 2000 zone (motorized vehicles prohibited). The Hamoir-Sy and Palogne-Bomal stretches are priorities in the Durbuy 2024-2030 municipal declaration. The ultimate goal: connect the Ardennes to the Netherlands via Liège.
Municipal Mobility Plans: advisory bike lanes (chaucidou), P+R park-and-rides, safe school mobility — inspired by the Walloon FAST 2030 strategy.
The Ourthe Country LAG (Local Action Group - Durbuy, Erezée, Hotton, Houffalize, La Roche, Manhay, Rendeux) pilots rural innovation via the European LEADER program. It deploys Renewable Energy Communities (REC), fast electric charging networks, and supports agricultural cooperatives in short supply chains.
IDELUX Strategic Plan 2026-2028: heating networks (biomass/geothermal), energy renovation of public building stock, Quai de l'Ourthe square in La Roche-en-Ardenne, Houtopia (Houffalize), Parc Chlorophylle (Dochamps).
❓ Questions & Answers
The strategy is shifting towards the principle of "making room for water." Old techniques like systematic dredging are replaced by soft methods (brush clearing/coppicing) because they are ecologically damaging. Heavy investments are planned, including €13.4 million to renovate the Nisramont dam.
The region faces an aging population and a reduction in household size. This generates strong land pressure (peri-urbanization) requiring the creation of 7,000 housing units per year in Wallonia by 2040, while combating urban sprawl.
Tourism is transitioning towards sustainability. In Durbuy, the 2024-2030 policy declaration aims for resilient, low-energy tourism. A major urban renewal project in Barvaux benefits from €18 million to demineralize the space and redevelop the banks of the Ourthe.
The University of Namur and the Ourthe River Contract use a 3D augmented reality sandbox (EXACT LAB project) to allow local stakeholders to instantly visualize runoff dynamics and the exposure risks of infrastructure during floods.
The LIFE projects (such as LIFE Pays Mosan and LIFE Ardennes Valleys) aim to restore fragile habitats, secure karst networks for bats, and replace spruce monocultures with native deciduous forests to increase soil water retention.
