Digging into the costs of urban soil rehabilitation

Urbanization leads to soil compaction, pollution and sealing, degrading the ecological functions of soil and ecosystem services essential for urban resilience, such as flood mitigation and climate regulation. Ecological rehabilitation of urban soils is thus critical for sustainable and climate-adapted cities. However, the economic dimensions of urban soil rehabilitation, particularly its costs, remain unexplored. Here we estimate that, in France, median urban soil rehabilitation costs range from €50 m⁻² to €310 m⁻² for compacted, sealed or built-up soils, escalating to over €800 m⁻² for polluted soils. Urban soil rehabilitation involves a sequence of up to ten steps, combining several techniques, with substantial cost variation. Preliminary analyses—pre-intervention diagnostics to guide technical choices—are the least expensive step, while building deconstruction and pollution remediation are the most costly. These cost estimates will facilitate the prioritization of rehabilitation areas and the development of economic incentives for ecological rehabilitation in cities. These findings also highlight the need for healthy soil preservation, alongside rehabilitation efforts.