investment-in-nature-close-infrastructure-gap-annex-6b1f8f18c98a0739.pdf

This document is an annex to a report by the International Institute for Sustainable Development (IISD) that evaluates the potential for Nature-based Infrastructure (NBI) to reduce the global infrastructure investment gap. It provides a literature review of infrastructure needs across sectors such as water, energy, and transport, and compares the costs and value generation of NBI against traditional 'grey' infrastructure using SAVi assessments.

• The document estimates that Nature-based Infrastructure (NBI) can cover between 9% and 14% of the global infrastructure gap, with a calculated average potential NBI investment of USD 488.95 billion per year, representing 11.40% of the total annual need.
• Across various sectors, the potential share of investment that could be filled by NBI varies significantly: 50% for agriculture and climate resilience, 25% for water and sanitation, 10% for energy efficiency and transport, 5% for energy supply, and 20% for irrigation.
• Analysis of 10 SAVi assessments indicates that NBI is more cost-effective than grey infrastructure, costing an average of 50.6% less and generating 29.1% more value. NBI generates USD 10 for every dollar invested, compared to USD 3.6 for grey infrastructure.
• NBI provides specific functional alternatives to built infrastructure: vertical-flow treatment wetlands can reduce chemical oxygen demand, total suspended solids, and ammonium by up to 90%; urban green spaces are on average 1°C cooler than built-up areas; and permeable pavements can reduce stormwater runoff by 70%–90%.
• The document highlights specific economic benefits of NBI in cities: Houston's 663 million trees provide cooling that reduces air conditioning needs valued at USD 131 million annually, and San Francisco's urban forest canopy saves an estimated USD 27 million in natural gas and USD 305 million in electricity costs.
• In coastal protection, NBI can be more cost-effective than grey infrastructure. In Lami Town, Fiji, benefits for NI-based coastal adaptation were estimated between FJD 8 and FJD 19.50 for every dollar spent, whereas engineered options reaped benefits of FJD 9 but required higher damage avoidance assumptions.

APA

International Institute for Sustainable Development (n.d.). investment-in-nature-close-infrastructure-gap-annex-6b1f8f18c98a0739.pdf. https://nbi.iisd.org/wp-content/uploads/2021/10/investment-in-nature-close-infrastructure-gap-annex.pdf

Chicago

International Institute for Sustainable Development. investment-in-nature-close-infrastructure-gap-annex-6b1f8f18c98a0739.pdf. n.d. https://nbi.iisd.org/wp-content/uploads/2021/10/investment-in-nature-close-infrastructure-gap-annex.pdf.

Wikipedia

{{cite report |author=International Institute for Sustainable Development |title=investment-in-nature-close-infrastructure-gap-annex-6b1f8f18c98a0739.pdf |url=https://nbi.iisd.org/wp-content/uploads/2021/10/investment-in-nature-close-infrastructure-gap-annex.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{internationalinstituteforsustainabledevelopmentndinvestmentinnaturecloseinfrastructuregapannex6b1f8f18c98a0739pdf, author = {{International Institute for Sustainable Development}}, title = {{investment-in-nature-close-infrastructure-gap-annex-6b1f8f18c98a0739.pdf}}, institution = {International Institute for Sustainable Development}, url = {https://nbi.iisd.org/wp-content/uploads/2021/10/investment-in-nature-close-infrastructure-gap-annex.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }