River Peffery Restoration Project Final Report

The Peffery Restoration Project has re-meandered a straightened, deepened section of the Peffery River close to the small settlement of Fodderty. The project was conceived, developed and managed by Richard Lockett and Hannah Humphreys of Lockett Agri-Environmental with the aim to increase biodiversity on the site and contribute to the reduction of flooding in the downstream town of Dingwall.

Initial research into the feasibility of the project was carried out in 2020. This feasibility study set out how the restoration work could reconnect the main channel of the Peffery to its natural northern floodplain by removing two short sections of the current embankment structure and creating a new river channel. The report advised that a full, detailed topographical survey would be essential to confirm that the river and floodplain levels would allow for the restoration as planned.

Funding for this topographical survey was kindly provided by the Pebble Trust and the survey was carried out over four days in December 2020. The topographical survey results provided a wealth of essential data when applying for the NatureScot Biodiversity Challenge Fund (BCF) for the construction of the new river channel.

Without the Pebble Trust providing the stepping stone of the survey required to gather topographical data, we would not have been able to progress the project.

The BCF application was successful and the river restoration took place in September 2022.  The river was successfully re-meandered, increasing its length by a third from 450m to 600m. as well as a total of 6.5 ha of new habitat created on its floodplain.  New floodplain habitat comprises a mosaic of wetland, swales, backwaters, marshy grassland, improved grassland which will revert to a species-rich composition over time, and a combination of planted / regenerating trees and scrub.

The new river channel has also improved connectivity of habitats and the river now joins the original small area of wetland and pond present at the site.  Floodplain wetlands, backwaters and ponds have further increased habitat heterogeneity of the area and gravel extracted from the old channel was used to line the new channel to ensure optimum transfer of species including freshwater invertebrates, microbes and algae.

Trees removed to create the new channel have been recycled for use within the restoration site as large woody debris structures or tie-in bank protection.  These features encourage the trapping of sediment forming fish habitat and structural diversity whilst decreasing diffuse pollution.  This offers a host of ecological and geomorphological benefits lending itself to a stable and sustainable riparian ecosystem.  Tree cover on river edges reduces the temperature of the water (rising river temperatures risk having a significant effect on fish populations, particularly in the Highlands), provides food via leaf litter for freshwater insects that the fish rely on for food, and any trees that fall into the river encourage the build-up of gravel for spawning and provides shelter.

Although the original channel was straightened and deepened, it was also shaded by mature native woodland. This woodland means that the River Peffery has a very healthy fish population. A fish rescue operation was carried out over two days prior to the de-watering of the old channel. Over 1,600 fish were extracted during this work. The fish rescue involved a team of local volunteers in co-ordination with the Cromarty and Ness Fisheries Boards.

Species found within this stretch of the river included trout, salmon, lamprey and eels. Although the new channel is currently less wooded, creating a re-meandered channel has increased the length of the river and increased the complexity of the gravel bed and banks in comparison to the old, straightened channel.

In the short term, the tree cover has reduced. However, the embedded root plates and tree tops in the banks of the river simulate the benefits of riparian woodland. Some of the banks will be planted with trees donated by the Woodland Trust in the winter 22/23 to encourage riparian woodland to develop. We anticipate considerable natural regeneration of trees and shrubs on the site in the coming years. The health of the fish population will be monitored by the Cromarty Fisheries Board, contributing to research on re-meandering as a management tool for our river ecosystems.

The initial funding provided by the Pebble Trust was crucial in enabling this River Peffery Restoration Project to go ahead. The beneficiaries of which include biodiversity, the local community and climate.

Further projects planned as a result of the River Peffery Restoration Project. The River Peffery Wet Woodland Project aims to create 2.3 ha of wet woodland on the south side of the Peffery floodplain at Fodderty and work on this will commence in spring 2023.

We have also recently received funding for the River Peffery Catchment Project. This presents an opportunity to plan, and implement, ecological restoration and natural flood management techniques within the whole catchment, helping to reduce the flood risk to Dingwall whilst enabling nature to thrive and will be carried out in the first half of 2023.