A floodplain is a large, flat expanse of land that forms on either side of a river, stretching to the valley edges. Created over thousands of years as the river meanders back and forth across the valley floor, floodplains are a dynamic system that provide a range of benefits to the ecosystems and communities that surround them.
Stretching between Kingussie and Kincraig along the River Spey, RSPB Scotland Insh Marshes is a 1,000 hectare floodplain. Due to historical modifications, this amazing floodplain is unable to function in a sustainable way, with knock-on negative impact on floodplain management, wildlife and people.
Working with the local community, we’re developing a long-term vision to transform Insh Marshes into a prime example of a restored floodplain and river system. These changes will help increase the resilience of local communities and the natural riches of Insh Marshes against climate change and provide a home for a range of important species such as Spotted Crake and String sedge.
Working with river experts and building on previous work, we explored a range of restoration options and concluded that the preferred option is to realign the lower part of the River Tromie through the Invertromie field to the west. This option will have the maximum benefits as a restored ecosystem whilst reducing risk to infrastructure and flooding, bringing benefits for people, nature and climate.
We are proposing a new channel across the Invertromie fields, so that the pressure on the east bank will be reduced, and a more natural channel will develop to the west. The planning application for this proposal will be submitted in early 2025.
More information is available here.
Since our first river restoration project in 2022 where 9 uprooted trees were submerged in the River Tromie, we have seen extremely high rainfall events and significant flooding. The high flow flood events are the ones that shape the river the most, carrying sediments and sometimes large cobbles downstream. The trees – also known as woody material – have interrupted this sediment flow, creating new river habitats and niches. Where once we were seeing uniform cobble size throughout the riverbed, we now have a mixed size of material building up around the tree roots. Nature thrives in diversity, and it is this diversity of gravel size that creates the right conditions for spawning fish. We have also seen the creation of deeper pools in front of the roots. These deep pools of slower moving water provide resting and feeding opportunities for freshwater fish.
The storms of winter 2023-24 have further weakened the embankments of the River Tromie as it flows through RSPB Insh Marshes. As the artificial banks prevent sand and gravel from spilling over into the floodplain, it accumulates on the riverbed unnaturally raising the water level and speed of flow. This increase in flow erodes and breaches the banks, potentially impacting on neighbour’s land, infrastructure, and the ecology of the Reserve, so doing nothing is not an option.
Reflecting on this development, and the real time impacts of climate change, the team decided to prioritise developing a long-term solution for the River Tromie.
In May and June 2023, we held River Restoration events for our neighbours, nearby communities, and a range of stakeholders. The purpose of these events was to share an update on our work, as well as provide an opportunity for people to ask any questions about how we plan to meet the challenges of climate change, flood resilience and historic floodplain modifications at RSPB Insh Marshes.
Towards the end of 2023, our expert consultants completed a report with more detailed analysis and recommendations for work on the River Tromie, the Raitt’s Burn and the Lynchat wetland. This report took into account previous community consultation, stakeholder views as well as expert modelling and analysis.
The RSPB Insh Marshes team have been working on a thorough response to feedback and questions asked during the community engagement in 2020. This has included commissioning some further work from the consultants, EnviroCentre, and giving careful consideration to the questions and concerns raised:
Any questions that we cannot currently answer are being held here, and will be addressed as and when further information becomes available.
Following these discussions, the first floodplain restoration project got underway in Autumn 2022. Nine spruce tree trunks were strategically installed in the River Tromie. The woody material will help to create pools and areas of sediment build-up, which is beneficial to spawning and feeding fish such as Atlantic Salmon. It will also slow the flow of water, which should help to reduce the peak of any future floods. Read the full story here.
There are three other projects that we are still considering alongside the feedback, support and concerns from the local community, but they will not be taking place for a number of years. We have appointed a dedicated Project Manager to oversee this work alongside the Insh Marshes team.
Despite the challenges of a global pandemic, throughout the winter of 2020, we undertook extensive community engagement to inform and provide opportunities to input on the river restoration work.
The ideas, concerns and suggestions gathered during this consultation phase helped to shape the proposal for the future of Insh Marshes, released for consultation in 2022.
Click here for an overview of the 2020 Community Engagement.
By 2019 we had some possible options for floodplain restoration projects which would help to restore the marshes for people, nature and climate. It was important to engage with the local community with these options at as early a stage as possible, to shape proposals well before any planning application was made.
Historical modifications mean that natural processes on the marsh are restricted. There is growing concern that current management of the reserve is unsustainable, and it is becoming increasingly difficult to maintain some of the designated features and habitats it is recognised for and the ability to keep them in a favourable condition.
In 2016, RSPB Insh Marshes commissioned a feasibility study, funded by SEPA's Water Environment Fund and Cairngorms National Park Authority, to look at options for the future to ensure the sustainability of Insh Marshes not only as an important site for flora and fauna but by continuing to offer flood protection.
EnviroCentre, our Environmental Consultants, created a computer model using data collected from the marsh and previous flood events. This model assessed the current conditions and offered different options to restore the river and floodplain by removing redundant embankments to reconnect the river and floodplain, initiating in river process where tributaries have been straightened and canalised, and reducing the drainage function of the defunct ditch systems to reduce the a negative impact on protected wetland habitats.
These different options underwent rigorous assessment and stakeholder engagement to assess viable options for the future of a healthy, safe and nature-rich Insh Marshes.
You can download a summary of these options here, and the full feasibility study is available for download here.
In the 18th and 19th century, humans extensively modified Insh Marshes floodplain, to create land for agriculture.
These modifications were never fully successful, mainly due to the dynamic nature of the floodplain. With population decreases from the 1800s onwards, they quickly fell into disrepair and once heavy machinery was introduced in the early 20th century, people were unable to tame the marshes, being restricted to the edges for hay crops and grazing.
