Navigating the terms “Green Infrastructure”, “Nature-based Solutions” & Co.
By Stephanie Vo, Senior Water Policy Associate
“Green infrastructure” has become a buzz word – but so has “nature-based solutions”...and “natural climate solutions”? Navigating these and other synonymous terms can be confusing. This blog delves into this entanglement of terms, suggests how to approach them, and clarifies how we use them at EPIC.
When we talk about integrating nature and human-made infrastructure, we’ve gotten pretty creative with the various words we use to describe it. Green infrastructure is one way to do it, but there are varying definitions of green infrastructure as well as other related terms, like nature-based solutions and natural climate solutions (see list below), that span disciplines from stormwater management to climate change adaptation. Technical term redundancy, as described in a previous blog on “Pay for Success”, stems from varied use in government, layers of underlying policy, and unstandardized metrics for benefits. The redundancy and variance can be helpful, as it makes terms and definitions flexible to a specific locality’s needs and context; however, they can lead to inconsistent and unconcerted efforts in implementation. In reality, we might all be talking about the same thing.
Last November, the Biden-Harris Administration released its Roadmap for Nature-Based Solutions (Roadmap), which lays out a strategy for increasing actions that “protect, sustainably manage, or restore natural or modified ecosystems to address societal challenges, providing benefits to both people and the environment”. While it uses the term nature-based solutions (NBS) to describe these activities, the Roadmap acknowledges that there are varying terms used by different federal agencies and in multilateral agreements to describe the same concept. In its acknowledgement, it encourages alignment towards a common definition.
Green infrastructure, nature-based solutions, and related concepts are all hybrid systems that provide an array of societal and environmental benefits, and these benefits can help address an array of challenges. They not only help with stormwater management, but also promote community revitalization, improve air quality, provide habitats for local fauna, and much more. Whether it’s green infrastructure or nature-based solutions, these projects have the potential to tap into a wide array of different funding sources because their benefits are wide ranging. Limiting their definitions to, for example, hydrologic systems that help meet regulatory requirements limits project funding and integrative opportunities. When agencies and departments use their own definitions and terms, it leads to siloed work. We need integrated and comprehensive solutions, especially when our communities face immense challenges, such as climate change and systematic injustice.
As we move from a paradigm of pure engineered solutions towards a hybrid approach of using nature as viable solutions and actual infrastructure, we’ll need to think about our use of terms and assumptions. At EPIC, we often use green infrastructure to refer to those techniques that integrate nature and human-made systems as solutions to a variety of environmental and public health challenges. We turn to that term most often because we work with regulatory water issues and the EPA, which also commonly uses the term green infrastructure–it’s what many practitioners and advocates in the US water infrastructure space are comfortable with. But we’ve had conversations internally and with partners about whether this is the right term to be using–should we use green infrastructure or natural infrastructure or nature-based solutions or natural climate solutions to best describe what we mean? The list goes on, and new terms seem to emerge continuously.
So where do we go from here? We should work towards a common term and definition that encompasses a broad, holistic understanding of all the multi-benefits these systems can bring. As you can see below, the list of almost-synonyms is sprawling, and it will be hard to wrangle this into one cohesive term and definition across several disciplines. But I do see a trend towards integrated thinking when I look at the Roadmap’s use of nature-based solutions or at what organizations, like Greenprint Partners, are doing in the green infrastructure space.
We’ll continue to use green infrastructure and nature-based solutions most often here at EPIC, because those terms are regularly used in the policy and research spaces in which we work and have definitions that we find holistic and interdisciplinary. We believe that they are true synonyms and will use them interchangeably, but recognize that at this point, these terms stem from different disciplines and are used in different policy arenas. We hope that all these terms can converge so that communication between scientists, nonprofits, and policymakers is streamlined and that we can effectively use this powerful concept of nature as viable solutions and infrastructure to align a range of critical policy objectives.
| Term | Definitions |
|---|---|
| Green infrastructure (GI) | At the neighborhood scale: refers to systems that replicate natural processes by storing, infiltrating, or evapotranspiring water, like rain gardens and green roofs. At city or county scale: refers to natural areas that can address nonpoint source pollution, provide habitat, flood protection, water filtration, and clean air, like wetlands and forests. Most often used by the U.S. EPA and in stormwater contexts. |
| Nature-based solutions (NbS or NBS) | “Actions to protect, sustainably manage, or restore natural or modified ecosystems to address societal challenges, simultaneously providing benefits for people and the environment” (the Roadmap); most often used in a climate change context and at the international level |
| Blue-Green Infrastructure | Similar to green infrastructure, but includes emphasis on “blue” elements, such as rivers, canals, and ponds. Since these elements are inextricably intertwined with natural elements, there isn’t much need to parse them out. |
| Ecological infrastructure | A synonym for green infrastructure; stems from an ecosystem services line of thought; refers to any part of nature that provides benefits to an urban area. |
| Engineering with nature | A synonym for nature-based solutions; the use of natural systems to deliver economic, environmental, and social benefits; spearheaded by the US Army Corps of Engineers. |
| Green Stormwater Infrastructure (GSI) | A synonym or subset of green infrastructure with a stronger focus on stormwater management. |
| Low-impact development (LID) | A synonym for green infrastructure; also has a strong focus on stormwater management. |
| Natural climate solutions (NCS) | A synonym or subset of nature-based solutions; focused on climate mitigation; refers to conservation, restoration, or other land management that increase carbon storage or decrease greenhouse gas emissions; can include forests, saltmarshes, seabeds. |
| Natural infrastructure | First used to highlight the significance of wetlands and more natural, less engineered landscapes, like coastlines or wetlands, but still includes an active management component. |
| Stormwater best management practices (BMP) | Often used as a synonym for green infrastructure; includes actions that reduce pollution in stormwater runoff in urban, residential, and agricultural areas. These actions include green infrastructure, but do not necessarily need to utilize natural elements–an example is silt fencing. |
| Stormwater control measures (SCM) | Similar to stormwater best management practices, see above. |
| Sustainable urban drainage systems (SuDS or SUDS) | Synonym for green infrastructure; refers to a more natural approach to managing stormwater. |