Water resources in humid regions are perceived as abundant, and water-governance systems are based on the expectation of consistent availability of water to meet all needs. In arid regions, in contrast, the operating assumption is that water is a scarce resource that must be allocated systematically to avoid conflict. The ‘myth of abundance’ common in humid regions is counterproductive to effective water governance. This paper provides an overview of the concepts of water scarcity and water security and explains how water governance in humid regions fits into these frameworks. It then addresses the riparian system for allocating water rights and how this system promotes the myth of abundance. Three case studies are presented from humid regions of the Anglophone world, highlighting the shortcomings of abundance-based water-governance systems in these regions. Finally, the water-security framework is advocated as an alternative that addresses fundamental flaws of the abundance-based approach, namely issues related to ecosystems, water quality, disasters, and conflict. Using a goal of water security, rather than a perception of abundance, as the basis for water governance will lead to improved outcomes, especially given future climate change and population growth.