iTree Design & Biodiversity Metric Tool
This solution was sourced in response to UKGBC’s Innovation Challenge: “How can communities and local authorities implement, maintain, and assess the impact of nature-based solutions to enhance climate resilience?”
Understanding and measuring the benefits of natural capital can be challenging and complex due to the multitude of factors. These solutions make analysis easier through capturing biodiversity and ecosystem service values for proposals at early design stages.
This solution enables developers to rapidly understand natural capital impacts as they iterate through designs. It allows changes at the earliest stage of the development process, hugely increasing the likelihood of successful retention/addition of natural capital in the build stage. The solution includes 2 key outputs which will enable accessibility to a wide range of users from communities and local authorities to consultants, developers, and engineers at the design stage. The Natural Capital and Biodiversity Design Tool captures biodiversity units alongside ecosystem service (ES) values, using i-Tree Eco.
The solution, incorporates two stand-alone metrics:
- i-Tree Design – Developed by the United States Forest Service, Davey Tree Expert Company and other collaborators.
- Biodiversity Metric 2.0 (BM 2.0) – Developed by Natural England.
Currently, using a grid reference or similar, the user can find a location and plot a polygon to cover the footprint. Once the user has inputted the planting/landscape design, the tool calculates current ES values and uses them along with the species of tree specified, geographical and climatological data to predict growth rates and model the ES values into the future. This creates the “natural capital breakeven point” i.e., the year at which the new planting will replace the values lost because of the scheme. ES are also quantified (kg) and valued (£). The monetary expression of ES in GBP further illustrates the economic, environmental and community gains of projects in a format which is digestible by those who work in construction design through to local councillors and those who reside and work in local communities.
- Free software – open access i-Tree Design tool. This output is simple to use, and easily accessible for community projects.
- Premium software – subscription service for commercial projects – designed for local authorities and consultants, incorporating both i-Tree Design and Biodiversity Monitoring 2.0.
Verification & Case Study
In 2015 Treeconomics undertook a Natural Capital valuation of National Highways’s ‘soft estate’. This project comprised of an environmental and economic benefits assessment of the trees, shrubs, soils and grasses in ‘Area 1’. This was followed by an ecosystem services (ES) review – to establish other ES which could be measured, quantified and valued – and a concept design cost/benefit calculator.
Following the success of this work in 2015, in 2018 National Highways and Kier commissioned Treeconomics to further develop the concept design tool through improvements to usability and format, publishing as a web application. The NCBD Tool was the next stage where BM2.0 was added and adjustment features were developed. The Natural Capital Valuation study and the NCBD Tool has been used by Kier Highways’ designers to ensure that infrastructure projects result in no net loss of ES. As a result of taking account of surrounding natural environments, projects are generally more successful in winning funding.
For the first time, a tool can deliver the holistic picture of environmental impacts and benefits in a monetised way that can be used to demonstrate true value for money and give a Benefit Cost Ratio that takes everything into account, influencing decisions and designs.