Upper Spey River Restoration Project

Improving river habitat and climate change resilience in the upland headwaters of the Spey.

This project was supported by the NatureScot Nature Restoration Fund.

In remote Glenshero on the western margins of the Spey catchment, the upper Spey runs for around 18km until it reaches Spey Dam near Laggan. This project looked to improve habitat for the benefit of all wildlife in and around this important part of the river, and especially to make conditions as favourable as possible for breeding salmon and trout, whilst also helping to increase resilience to the effects of climate change.

In 2022, 65 Large Woody Structures (LWS) were installed along around 5km of the upper Spey to encourage formation of more complex, diverse physical structure and higher quality in-channel habitat. Deadwood is a crucial element of functioning river systems, and LWS can be used to mimic natural deadwood until new native woodland can be created along the river banks.

Project Delivery: What did we do?

The Upper Spey River Restoration project was completed in 2022.

1. We began by selecting and preparing the sites

Our initial efforts involved detailed site assessments and GIS mapping to identify strategic locations for Large Woody Structures (LWS). This meticulous planning ensured the LWS would be positioned to maximize their ecological benefits, enhancing the river’s natural processes.

2. We installed Large Woody Structures

Large Woody Structures, composed of felled trees with their root plates still attached, were carefully positioned along the river. These structures were anchored securely into the riverbanks and bed, using surrounding boulders for additional stability. The LWS are designed to mimic natural debris, encouraging diverse flow patterns and supporting habitat complexity, which is crucial for various aquatic species.

3. We minimised environmental impact during construction

Throughout the construction phase, we took extensive measures to limit ecological disturbance. This included controlling sediment release and minimising soil disruption, ensuring that our activities preserved the integrity of the riverine environment.

4. We established a comprehensive monitoring strategy

After installing the LWS, our focus shifted to monitoring their ecological impact. We implemented a series of monitoring techniques, including electrofishing surveys and fixed-point photography, to track changes in habitat quality and river morphology over time. These efforts help us assess the effectiveness of the LWS and guide future river restoration projects.

What are the Benefits of this Project?

1. New habitats have been created for our wildlife

The LWS are reintroducing varied flow patterns in the river, and especially in high flows we are seeing rapid formation of gravel bars and deeper pools around the structures. These provide much more types of habitat than the fairly uniform channel which characterised this part of the river previously, supporting not just fish but also the insect and microbial life which the whole food chain depends on. As the wood slowly breaks down it adds organic nutrients into the system which are often at artificially low levels in unvegetated upland rivers like this one.

2. Climate change resilience is boosted

Because of rising peak air temperatures, bare, unshaded rivers such as the upper Spey are vulnerable to high water temperatures which threaten fish and other aquatic life. Climate change is also causing more frequent and severe flood and drought events. The shelter and deep pools created around the LWS provide valuable refuges for wildlife to escape extreme conditions and survive getting overheated or washed out.