B£ST (Benefits Estimation Tool)

CIRIA has developed a free tool and guidance, B£ST (Benefits Estimation Tool – valuing the benefits of blue-green infrastructure) for use on PCs. It makes assessing the benefits of blue-green infrastructure easier, without the need for full scale economic inputs. B£ST was first produced and released in 2015 and it has been updated in 2019.


B£ST is used to assess and monetise many of the financial, social and environmental benefits of blue-green infrastructure. The results enable users to understand and quantify the wider value of SuDS and natural flood management measures. This can support investment decisions and can help to identify stakeholders and find potential funding routes.


The current version of the guidance supersedes the original (2015) version. The key changes are presented in the table below.

The usability of B£ST has been improved, it follows a simple structure that begins with coarse screening and qualitative assessments to quickly identify the benefits to evaluate further. It then provides support to help quantify and monetise each benefit. On completion of the evaluation, the tool provides a series of graphs and charts to present the benefits based on Ecosystem Services (ESS) and Triple Bottom Line (TBL) criteria. In the future it will also provide Natural Capital accounting.


Please be aware some of these free downloads require logging in, or registration into the CIRIA website. To download the tool, please follow the instructions and "Add to Cart".


W047a B£ST: Benefits Estimation Tool – Valuing the benefits of blue-green infrastructure (Release 4. 1 12/02/19)
W047c B£ST: Comparison Tool – Enables the comparison of more than one assessment (Release 3.01 12/02/19)


W047b B£ST: Guidance – Guidance to assess the benefits of blue and green infrastructure using B£ST (Release 4.01 12/02/19 - based on 190104)

B£ST - Presentation - PPT with notes (Release 2, 12/02/19)

Other B£ST resources

B£ST is underpinned by evidence and information, these have been reviewed and used since 2013 and links to information can be found here.

Demonstrating the multiple benefits of SuDS - A business case - Literature review (2013)


Demonstrating the multiple benefits of SuDS - A business case - review of sources (2015)
Making B£ST better - Evidence review summary (2018)


We will be included case studies with completed valuation spreadsheets in the forthcoming weeks.

B£ST focuses on the benefits of blue-green infrastructure, rather than the costs. There have been projects and initiatives to capture the costs of SuDS. However, cost information is going to be very context specific depending on the site, the design approach, components and maintenance arrangements. Further information on costs can be found here.


We would be very keen to understand how you found using B£ST so we can make any necessary changes. If you have any feedback it would be helpful if you could please complete this simple survey.


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