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.

2015 version

2019 version

Focused on SuDS measures only

Also includes NFM (natural flood management) and other elements of blue-green infrastructure

Includes evidence up to 2015

Includes evidence up to 2018

Monetary values in 2014 prices

Monetary values in 2017 prices

Includes 19 monetised and 4 non-monetised benefit categories

Following rationalisation and addition of new categories (noise and traffic calming), includes 15 monetised and 3 non-monetised benefit categories

Results presented for ecosystem service and triple bottom line categories

Interactive results dashboard in tool

Detailed information requirements

Information requirements set out more clearly for both simple and detailed assessments

Results presented in terms of ecosystem services and triple bottom line

Results presented in terms of ecosystem services and natural, social and other capitals

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 in terms of ecosystem services and natural, social and other capitals.

B£ST 2019 tutorials are available to view on our YouTube channel.
Click here to view B£ST tutorials.



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".

B£ST 2019 tools

W047a B£ST: Benefits Estimation Tool – Valuing the benefits of blue-green infrastructure (Release 5.1.1 20/09/19)
W047c B£ST: Comparison Tool – Enables the comparison of more than one assessment (Release 3.01 12/02/19)

B£ST 2019 guidance

W047b B£ST: Guidance – Guidance to assess the benefits of blue and green infrastructure using B£ST (Release 5 v0B June 2019)

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

B£ST 2019 case studies

A number of case studies using B£ST 2019 have been developed. These include the B£ST spreadsheet (.xls) and the case study information (pdf).

Burpham Court case study
Burpham Court B£ST spreadsheet

Clothworkers Wood case study
Clothworkers Wood B£ST spreadsheet

Killingworth and Longbenton case study
Killingworth and Longbenton B£ST spreadsheet

Roundhay Park case study
Roundhay Park B£ST spreadsheet

Glasgow SWMP case study
Glasgow SWMP B£ST spreadsheet

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 including 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.


Our Partners
Our Supporters