The Sussex Flow Imitative (SFI) provides working examples of Natural Flood Management (NFM) techniques and best practice NFM projects. We promote a landscape scale approach to reducing flood risk and water shortages, and to promoting the wider uptake of NFM in other suitable catchments. Over the past five years SFI has delivered a large number of NFM projects, demonstrating a range of different NFM techniques. These provide case studies and working examples of how NFM can be practically applied in lowland catchments.
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The main NFM methods SFI have used over the last five years are:

​Restoring natural processes through reconnecting river channels, meanders and floodplain washlands - area equivalent to 4.95 hectares of floodplains have been reconnected. 

​Providing advice on land use and controlling excessive run-off and erosion - advice given to 11% of catchment area.

​Increasing the roughness of the catchment through enabling the expansion of woody areas and planting 10.2km of native hedgerows, primarily across slopes and on floodplains. 

This is just a snapshot of the incredible achieves of the SFI project over the last five years, please read the full report to find about all the other amazing things we have done - full report.

Reducing use of plastic is our first priority:
Not using a tree guard is the most sustainable option. As a project we have been seeking to establish riparian woodland and cross-slope woodlands through processes or using techniques that don’t require individual tree protection.
 
Some of the methods we have been using are:

• Trialling planting at higher densities, having more sapling in a given area mitigates those lost as a result from browsing.

 

• Encouraging positive management for natural regeneration, thereby removing the need for planting altogether, with the resulting woodland being from local seed source and having greater variation in structure. However, natural regeneration doesn’t lend itself to when there are desired outcomes, such as targeting planting of surface water flow paths or introducing certain species that are present, such as black poplar.

 

• We have also been trialling alternatives to plastic guards, such as biodegradable one, and it is interested to monitor how these withstand the harsher environment of flood plains. As well as fencing off clumps or groups of trees to minimising the amount browsing the trees with experience.

Sussex Flow Initiative and the South Downs National Park Authority have created a Practical Guide for Farmers and Landowners for implementing Natural Flood Management measures. This new guide takes you through three levels of interventions from the quick and simple to the more complex multiple benefits schemes. Information is also included on costs and consents required for undertaking these works.

You can download the guide here

At the Sussex Flow Initiative (SFI), we are interested in all of the benefits that leaky dams provide, but we are particularly excited about their potential for making our landscapes more resilient to the extreme and unpredictable events of climate change. The benefits wheels below (taken from the Environment Agency’s Working with Natural Processes evidence base) helps to illustrate just how many benefits leaky dams can have across a whole range of ecosystem services.

SFI aims to create naturalistic structures that blend into the landscape, utilising local material where possible. There are a variety of types of the LWD, the three main types used by the project are outline below. Further information on these can be found in 'SFI's Leaky Dam Guidance Document'.

Banktop diverters 
Large woody debris is positioned and fixed across the banktop in streams and ditches, engaging high flows, holding back water and encourage it out onto the floodplain.  

These naturalistic structures emulate the natural process of wind blown trees or the dams that would have been created by beavers before they were lost from our landscape 400 years ago. The images below show how these structures can could just be a collection of sticks to fall length trees secured in place, but they are all:

• Improving water quality and reducing sedimentation in streams,
• Providing instream habitat and promoting new habitat formation,
• Kick starting natural processes to restore more natural stream habitat,
• Increasing drought resilience by holding back more water in the landscape; as well as
• Reducing flood risk.

Congratulations to all the amazing projects and individuals who won awards - more details can be found by click here. Thank you to our project partners, landowners, local communities and volunteers for their support, passion and hard work in protecting and enhancing Sussex.

What is social and natural capital?
Social capital is the benefits delivered to human health and wellbeing, and natural capital is the additional benefits delivered to nature and wider society, such as carbon storage for climate regulation, pollination for food production, and water purification. 

Working with New Economics Foundation, we attempted to document the true societal value of the partnership project work delivered by the project.

Social Capital Benefits of Sussex Flow Initiative
​Using bespoke surveys and spreadsheets, we found some really interesting insights into the true societal value of this project, here are some of the findings:

• SFI is really effective at improving the technical NFM skills of the people it involves, with an increase from a low starting point of 28.8% to 65.2%.
• People are more likely to take further action for nature and the environment as a result of their contact with SFI.
• The biggest gains came from increasing people’s connection with nature. People who attended one-off events felt more connected to nature after engaging with SFI.

Natural Capital Benefits of Sussex Flow Initiative
The UK government’s Ecosystem Services Databook was used to help calculate the wider natural capital benefits that the project has brought to society. In the eight years of the project, it has generated an incredible £1 million of public and natural capital benefits. This equates to a whooping £125,000 of benefits for every year of the project since 2012.

• Every £1 spent in delivering natural flood management generated >£2.14 of additional ecosystem value for the public good.
• The greatest societal value was generated through volunteering, water quality and flood mitigation aspects of the project.

These figures are based on seven key ecosystem services; timber provision, air pollution removal, carbon sequestration, flood regulation, water quality improvements, biodiversity and volunteering. Due to insufficient information/data it was not possible to calculate all the multiple societal benefits of all the work carried out by the project. Therefore, the true value will be greater than the £1 million. A significant portion of the work undertaken by the project delivers benefits that are incremental and will accrue greater value each year, for example the carbon storage will accrue over the lifetime of trees planted.

Having this evidence is an incredibly powerful tool, and a fantastic step to demonstrate real and wider value of the nature-based solution work of SFI.  

We’re eagerly awaiting the results from the group at Bangor University, and will use the findings to inform our NFM delivery. We will also be encouraging and supporting universities in the South East to carry out similar research in the lowlands, on the local soils, and focusing on the root morphology of species commonly found in our local hedgerows.

​References
1. Carroll, Z.L., Bird, S.B., Emmett, B.A., Reynolds, B. and Sinclair, F.L. (2004). Can tree shelterbelts on agricultural land reduce flood risk? Soil Use and Management, 20, 357-359.