Watersheds around the world are in peril and risk further decline from climate change and human impacts, like pollution, degrading landscapes, and unsustainable water use. These impacts can inhibit the ability of ecosystems to regulate water flows, sequester carbon to reduce atmospheric greenhouse gas levels, maintain biodiversity and healthy waterways, promote social well-being, offer economic opportunities, and sustain agricultural productivity. Climate change is exacerbating these impacts by shifting weather and precipitation patterns, degrading habitats, and increasing the recurrence and severity of natural disasters. Urgent action is needed to address these impacts by implementing nature-based solutions (NBS).
NBS protect, sustainably manage, and restore natural or modified watersheds, to address societal challenges effectively and adaptively, simultaneously providing human well-being and biodiversity benefits (IUCN, 2016). Investment in NBS offers a mechanism to restore degraded watersheds and protect intact ones, leading to improved water quality and quantity, improved carbon sequestration and increased biodiversity, among many other social and economic benefits. NBS also support climate mitigation and adaptation efforts and reduce the impacts from other shocks, such as floods, droughts, and extreme weather events. Implementing NBS can also help advance progress toward achieving the United Nations Sustainable Development Goals (SDGs), particularly SDG 2 (zero hunger), SDG 6 (water), SDG 11 (sustainable cities and communities), SDG 13 (climate action), and SDG 15 (life on land). NBS therefore support social, economic and environmental objectives, and may be particularly important in supporting vulnerable communities.
While investment in NBS has grown significantly over the last decade, several barriers hinder widespread implementation. A key gap is the lack of a standardized method to identify, account for, and value the numerous benefits of NBS. To address this, the project team, comprising the Pacific Institute, CEO Water Mandate, Danone, The Nature Conservancy and LimnoTech, are working to demonstrate how identifying and accounting for stacked benefits can help build the case for investments in NBS for watersheds. The outcomes and outputs from this project support public, private and non-profit sectors in supporting and/or developing effective policies, programs, and projects to incentivize greater implementation of and investment in NBS.
Stage 1: Launched in January 2020, Stage 1 of the project addressed the need for a standardized method and guidance, based on the outcomes from the project’s initial Landscape Assessment. This work focused on Benefit Identification and Accounting (Figure 1). A practical guide was developed through extensive stakeholder engagement and provides a method for identifying and estimating NBS benefits. This method has been compared to the outcomes and outputs of real-world NBS projects around the world and aligns closely with these case studies. Components of this stage have been developed into a user-friendly tool that will allow users to identify and account for benefits across multiple habitats and interventions.
The Benefit Accounting of Nature-Based Solutions for Watersheds project has produced several key outputs:
The landscape assessment was undertaken to inform the path forward for engaging the private sector to invest in NBS. A literature review was undertaken to understand the contemporary thinking around NBS and identify key opportunities and challenges faced by decision makers, practitioners, and researchers. Interviews conducted with businesses, civil society, and academia who have already implemented NBS project or are looking to do so yielded qualitative responses to complement or contrast the findings from the literature review. A review of NBS case studies from the private sector was also conducted.
This project developed a method to account for the stacked water, carbon, biodiversity, and socio-economic benefits of NBS for watersheds. This method is designed to align with existing tools and resources for NBS benefit accounting and incorporate lessons learned from NBS case studies globally.
By promoting the quantification of stacked benefits of NBS, this method can help to:
This guide was written to help organizations and individuals to identify (using the method developed) and account for the multiple benefits accruing from NBS investments. The guide indicates which specific NBS activities can be implemented in various habitats and suggests methods for estimating and measuring the benefits. Refer to Tables 5-9 in Section 3 of the guide for a summary of benefits and associated activities, indicators, and calculation methods.
Accounting for NBS benefits will improve a company’s impact monitoring and help build the business case for these “green” solutions, thereby supporting widespread implementation. Specifically, the guide helps users account for and measure the stacked water, carbon, and biodiversity benefits, as well as additional socio-economic benefits. The aim of this work is to increase the overall awareness of the value of NBS and increase investments in NBS, not only for ecosystem health and community development, but also for businesses and other stakeholders directly
The final product of this work is an online tool, the NBS Benefits Explorer, which adopts the developed method to identify and account for NBS benefits. Users of this tool will be able to select multiple habitat and intervention types to receive associated activity, process, and benefit outcomes. Benefits can be identified and accounted for across water quantity, water quality, carbon, biodiversity and the environment, and socio-economic themes.
The dynamic tool is highly intuitive and user friendly and will also inform the user of additional methods and approaches to further quantify the benefits identified. The tool is a key starting point for organizations looking to invest in NBS, or for those wishing to learn more about benefit identification and accounting. The tool will be updated to include further outcomes and outputs of this work.
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