By 2025, two thirds of the world’s population will be living in water stressed conditions. Meanwhile, the degradation of water ecosystems is occurring at alarming rates. Water utilities and water regulators that choose to play an active role in catchment management with nature based solutions (NBS) are uniquely positioned to help. Building a robust knowledge base and supporting opportunities for cross-sector collaboration are fundamental to the mainstreaming of NBS. The International Water Association (IWA) and The Nature Conservancy (TNC) are working together to encourage and facilitate active utility involvement in NBS, as well as promoting stronger connections between water utilities and regulatory bodies. Implementation of NBS involves multiple, interdependent stakeholders at various governance levels, and consequently regulators a key role in creating the enabling environments for these interactions and negotiations. This publication taps into diverse geographies and contexts, delving into case studies for a richer conversation that addresses the variety of challenges and elements for success for integrating NBS into water utility operations and planning. By publicizing successful case studies, the IWA/TNC partnership fulfils a dual purpose of endorsing these efforts and providing actionable guidance for other water utilities striving to improve their sustainability and resiliency.

Nature-Based Solutions and Water Security: An Action Agenda for the 21st Century presents an action agenda for natural infrastructure on topics of standards and principles, technical evaluation and design tools, capacity building and innovative finance. Chapters introduce the topic and concepts of natural infrastructure, or nature-based solutions (NBS) and water security, with important background on the urgency of the global water crisis and the role that NBS can, and should play, in addressing this crisis. Sections also present the community of practice's collective thinking on a prioritized action agenda to guide more rapid progress in mainstreaming NBS. With contributions from global authors, including key individuals and organizations active in developing NBS solutions, users will also find important conclusions and recommendations, thus presenting a collaboratively developed, consensus roadmap to scaling NBS. - Covers all issues of water security and natural infrastructures - Presents a comprehensive state of synthesis, providing readers with a solid grounding in the field of natural infrastructures and water security - Includes a fully workable and intuitive roadmap for action that is presented as a guide to the most important actions for practitioners, research questions for academics, and information on promising careers for students entering the field