The Environment Agency has published new guidance on building a business case for investment in multiple small sustainable drainage systems (SuDS) features over a wide area - known as the surface water investment model (SWIM) approach.
The SWIM approach aims to help the appraisal of multiple small SuDS features that deliver cumulative benefit and helps to make the case for SuDS delivery and secure FCERM grant in aid (GiA) funding for surface water flood risk management.
Small scale resilience projects aiming to reduce surface water flood risk often struggle to demonstrate viability for gaining FCERM GiA funding - this is because it can be difficult to quantify the benefits of small interventions like sustainable drainage systems (SuDS).
To be considered for funding, new project opportunities must initially follow the Flood and coastal erosion risk management funding policy guidance. The SWIM approach and its associated SuDS Programme Business Case (SPBC) should only be used when a project has been prioritised by the Environment Agency for development.
The SWIM approach accounts for the total benefits achieved by a package of small-scale SuDS measures by appraising the package of SuDS measures as a single intervention.
The Guidance says this approach:
- has the benefit of front-loading the approval of funding over a longer period and across multiple financial years
- enables greater flexibility for RMAs and means they can remain agile to opportunities that arise in-year - for example, being able to align your project timelines with other public realm works, which can lead to significant efficiencies
Some blue-green SuDS measures may also be eligible for funding through a standalone natural flood management (NFM) project. These projects follow a separate approval route, with their own single-stage business case template, benefits estimation methodology, and assessment tools.
SuDS Programme Business Case
The SuDS programme business case contains several main components as follows:
- Identifying benefit areas
- Options appraisal
- Economic appraisal
- Baseline
- Benefits
- Costs
- Apportionment
- Feature types
- Design standards
- Funding profile
The guidance says the SPBC template should be used to help make the case for the effective and efficient delivery of a package of SuDS measures and that the programme should be large enough to realise a meaningful reduction in surface water flood risk. As a guideline, it suggests users should consider a programme of around 2-5 years.
The Agency suggests that the SWIM approach should be used if you:
- work for risk management authorities (RMAs) responsible for managing surface water flood risk
- are Environment Agency staff involved in reviewing applications for Flood and Coastal Erosion Risk Management (FCERM) grant in aid (GiA) funding to manage surface water flood risk
- are a project manager, project executive, project board, senior user, project sponsor or work alongside others involved in the governance of FCERM investment projects
Contact email address for further information and support is: This e-mail address is being protected from spambots. You need JavaScript enabled to view it
Click here to access the SWIM guidance in full online
Click here to download the SWIM Business Case template documernt
Click here to access the Guidance on Standalone NFM project interventions eligible for FCERM funding in full online