Articulating the politics of green and blue infrastructure and the mitigation hierarchy for effective biodiversity preservation in France [Articuler la politique Trame verte et bleue et la séquence Éviter-réduire-compenser: complémentarités et limites pour une préservation efficace de la biodiversité en France], Chaurand & Bigard 2019

Compendium Volume 4 Number 2 January 2021

This article reviews the historical development of two pieces of environmental legislation in France – the use of the “mitigation hierarchy” to assess and limit environmental impact in project development and the promotion of ecological corridors. Theoretically, these two laws overlap when urban development projects in proximity to areas of ecological significance use the mitigation hierarchy (avoid, reduce, compensate) to ensure these zones are protected within the scope of the project.

  • 1976: “Protection of Nature” law in France introduced the mitigation hierarchy, aiming to avoid or reduce harm to the environment, or to compensate if harm is unavoidable.
  • 1992: Concept of “biodiversity” entered public discourse internationally, following the Earth Summit in Rio, Brazil.
  • 1996: France ratified European ecological corridor strategy.
  • 1999-2000: Concept of “sustainable development” emerged in France.
  • 2004: National strategy for protecting biodiversity adopted.
  • 2007: “Grenelle de l’Environnement” meeting created the “Trame Verte et Bleue” (TVB) policy (green and blue infrastructure, encompassing ecological corridors)
  • 2016: Biodiversity law enacted, creating national agency and regional committees on biodiversity

In spite of this policy evolution, commitment to ecological corridors has yet to move from a “TVB papier” to a “TVB de projets et d’action.” In other words, much discussion and mapping efforts have not yet resulted in the development of the imagined ecological corridor network. The authors speculate as to why this is so, explaining that the resources and coordination needed for enforcement are lacking. Even though “the creation, preservation and restoration of ecological connectivity” has been integrated into urban planning code, such considerations are often sidelined. Furthermore, definitions are vague: the objective of the TVB is the “good condition” of ecological continuity, but “good condition” is not defined. Lastly, taking action in defense of ecological continuity requires pro-active collaboration among levels of government from local to regional to national.

The authors propose better integration of these to policy tools. For example, the TVB designates certain non-protected areas throughout the country that are ecologically functional and serve a role in the eco-corridor network as key areas to “preserve.” With better communication between this TVB framework, the mitigation hierarchy could be applied at the level of “avoiding” harm to places designated as preservation priorities, but lacking formal “protected” status. In projects where harm is unavoidable, the mitigation hierarchy could be applied at the level of “reducing” harm to maximize the percentage of remaining green space as well as the permeability to wildlife of the built structures (such as passageways through fences). The “compensation” level of the mitigation hierarchy could be applied in the context of regenerating ecosystem function to areas designated in the TVB schema as needing ecosystem restoration.

The authors note that advocates for the TVB are clustered at the national level and within research institutions, while the people responsible for urban planning decisions are local and are not necessarily well versed in the scientific framework for the TVB. Local actors tend to focus on priorities other than ecological continuity. One measure to address this, according to the authors, would be the training of local “relays” to transmit knowledge of ecological principles vis a vis the TVB to local urban planners.

For the full PDF version of the compendium issue where this article appears, visit Compendium Volume 4 Number 2 January 2021