An approximately 700-m-long reach of the River Peffery near Dingwall, Easter Ross, was restored to a more natural condition that incorporated a sinuous channel and associated wetlands and backwaters
The river had been artificially straightened about 200 years ago with the aim of increasing agricultural productivity, although this significantly impacted the ecological condition of the channel/floodplain and added to the flood risk to Dingwall downstream. Historical assessments determined the previous highly sinuous planform of the river, with the specific restoration reach also being characterised by wet, marshy ground.
The process-based restoration design approach adopted aimed to reinstate this reference state condition, initially through constructing a physically appropriate sinuous channel and associated wetlands and backwaters. The final implemented design was specified through detailed assessments including topographic surveys, hydrological analyses, hydraulic modelling and stakeholder liaison, with specific site constraints and a native species planting scheme being incorporated into the final configuration. This initial design condition was implemented in summer 2022 and will evolve through the re-establishment of natural physical processes and vegetation succession, moving the project reach ever closer to its previous reference state. This trajectory of physical recovery will also drive significant ecological benefits and potentially reduce flood risk to Dingwall downstream (i.e., through greater retention of floodwaters within the project reach for certain sizes of flood event).