Diverse Approaches to Implement and Monitor River Restoration: A Comparative Perspective in France and Germany

Abstract

River restoration is a main emphasis of river management in European countries. Cross-national comparisons of its implementation are still rare in scientific literature. Based on French and German national censuses, this study compares river restoration practices and monitoring by analysing 102 French and 270 German projects. This comparison aims to draw a spatial and temporal framework of restoration practices in both countries to identify potential drivers of cross-national similarities and differences. The results underline four major trends: (1) a lag of almost 15 years in river restoration implementation between France and Germany, with a consequently higher share of projects in Germany than in France, (2) substantial similarities in restored reach characteristics, short reach length, small rivers, and in "agricultural" areas, (3) good correspondences between stressors identified and restoration measures implemented. Morphological alterations were the most important highlighted stressors. River morphology enhancement, especially instream enhancements, were the most frequently implemented restoration measures. Some differences exist in specific restoration practices, as river continuity restoration were most frequently implemented in French projects, while large wood introduction or channel re-braiding were most frequently implemented in German projects, and (4) some quantitative and qualitative differences in monitoring practices and a significant lack of project monitoring, especially in Germany compared to France. These similarities and differences between Germany and France in restoration application and monitoring possibly result from a complex set of drivers that might be difficult to untangle (e.g., environmental, technical, political, cultural).

Status of and Perspectives on River Restoration in Europe: 310,000 Euros per Hectare of Restored River

“…Surprisingly, only approximately 44% of the projects were part of large-scale (e.g., nationwide) river restoration policies, meaning that the majority of the EU river restoration projects comprised the individually planned actions of interested entities ( Figure 3C). projects completed (e.g., [26][27][28]) that we did not address in our analysis having no information, for example, on project budgets. However, collected data from 119 projects that have been well distributed in Europe we considered a reliable sample for the analysis.…”

“…We are also aware that in countries we got responses from there have been other river restoration We are aware that other European countries have implemented river restoration projects that we did not account for [26][27][28][29][30][31] having no responses containing information required for our analyses. We are also aware that in countries we got responses from there have been other river restoration projects completed (e.g., [26][27][28]) that we did not address in our analysis having no information, for example, on project budgets. However, collected data from 119 projects that have been well distributed in Europe we considered a reliable sample for the analysis.…”

“…Among the projects analyzed there were 56 projects from Western Europe (Austria, Belgium, Luxembourg, France, Germany, The Netherlands, Ireland, Spain and UK), 41 projects from Central and Southern Europe (Croatia, Hungary, Italy, Poland, Romania and Slovenia) and 23 projects from Northern Europe (Denmark, Estonia, Sweden and Finland). We are aware that other European countries have implemented river restoration projects that we did not account for [26][27][28][29][30][31] having no responses containing information required for our analyses. We are also aware that in countries we got responses from there have been other river restoration We are aware that other European countries have implemented river restoration projects that we did not account for [26][27][28][29][30][31] having no responses containing information required for our analyses.…”

“…We are aware that other European countries have implemented river restoration projects that we did not account for [26][27][28][29][30][31] having no responses containing information required for our analyses. We are also aware that in countries we got responses from there have been other river restoration We are aware that other European countries have implemented river restoration projects that we did not account for [26][27][28][29][30][31] having no responses containing information required for our analyses. We are also aware that in countries we got responses from there have been other river restoration projects completed (e.g., [26][27][28]) that we did not address in our analysis having no information, for example, on project budgets.…”

“…Then, the value added to such rivers by restoration remains only a share of the total value of the ecosystem service of these rivers. Moreover, restored rivers usually require some post-restoration adaptive management which also requires additional budget [14,15,25,27]. Hence, assuming that (1) restoration goals might not be fully met, (2) rivers before restoration still provide certain measurable services and (3) once the restoration has been completed, river still requires adaptive management, the calculated 7757 EUR·ha −1 ·year −1 should be considered a conservative, minimum-possible value of ecosystem meta-service of average European river.…”