Quantifying human impact during industrialisation on the evolutionary trajectory of Vosgian streams (NE France): the value of documentary archives

Since the Industrial Revolution, European rivers have faced increasing anthropogenic pressure through channelisation, rectification, and the construction of dams and weirs. The Vosges Mountains (NE France), a densely populated low-mountain range, exemplify this anthropisation, with approximately 5,000 hydraulic structures (HS), primarily levees and weirs, built across its main streams. Unlike major rivers like the Rhine, the edification periods of HS in smaller catchments remains largely unknown yet, hindering the reconstruction of environmental and human impact timelines.

This study investigates the spatio-temporal development of anthropogenic influence on three major streams in the southern Vosges—Fecht, Vologne, and Moselotte—focusing on morphodynamic changes since the late 18th century. We used extensive archival resources from the “Ponts et Chaussées” administration, including construction requests, plans, and reports from the 18^th to 20^th centuries. We first mapped existing HS to create an updated database, then dated their construction and, in some cases, deconstruction. We also reconstructed the diachronic evolution of the channel pattern, using an 1866 topographic map and orthophotos from 1951 and 2018.

Our analysis provides a first quantification of human influence, revealing that 12% (Fecht), 31% (Moselotte), and 56% (Vologne) of current weirs could be dated—mostly to the mid-19^th century. We also identified a strong correlation between HS construction and channel simplification. Despite archival limitations (e.g., loss or unavailability of documents), this study demonstrates the value of historical records in understanding long-term human impacts on river systems, offering insights that usefully complement field observations and investigations.