Potential for use of recycled water¹ is great, especially for agricultural irrigation, which comprises by far the highest percentage of water taken from developed sources in the arid and semi‐arid regions of the world. In California, 80% of developed water is used for agriculture, and the same pattern prevails throughout the western United States. The potential for recycled water use in agriculture remains under‐realized because of numerous impediments. Understanding how the incentives and impediments to agricultural reuse vary based on local context is critical to understanding the tradeoffs and technology requirements for different end uses of recycled water. Public perceptions about the safety of reclaimed water (from human waste) were a major impediment to water recycling until recent years. Several pioneers of water recycling have demonstrated—as specialists in the field of social psychology have hypothesized—that these attitudes are ephemeral and can be changed with proper outreach, demonstration, and education. Another impediment is the regulatory structure in some states. Water rights issues are another impediment specific to some western states in the United States. Cost differences for delivered water from traditional sources versus recycled water can be another challenge potentially requiring financial incentives in the interest of the greater good. One other impediment to the use of recycled water for agricultural irrigation is competition with other demands for the same water—landscape, golf course, industrial, and potable reuse. Potential for increased use of recycled water is great if impediments are removed and incentives are provided at the local, state, and/or federal levels to close the gaps (geographic and otherwise) between the utilities and the farmers.

Ecological economics, developed in the late 1980s, came to be known as the multi- and transdisciplinary science of sustainability. Since that time, it has blended basic and applied research with the intention of both informing and bringing change to environmental policy, governance, and society. However, many conventional economists have questioned its originality and contributions. This paper begins by clarifying the foundational perspectives of ecological economics that it engages an economy embedded in both real and limited ecosystems as well as socially constructed power relations. Herman Daly, a founder of the field, expanded on Nicholas Georgescu-Roegen’s entropy economics by focusing on a quantifiable sustainable scale of the economy and achieving justice in the control and distribution of economic benefits. He called for both quantitative analyses of economic scale and discursive approaches to a just distribution. The paper then discusses how the terms entropy, scale, and justice are used and interact in the literature, illustrated by some of the key debates in the field involving the Ecological Footprint, substitutability of natural and manufactured capital, and the growth—“agrowth”—degrowth debate. The debates also illustrate the potential for the field to influence policy. Ecological economics as the science of both sustainability and transformation can deploy numerous concepts and tools to provide insights on how to illuminate and solve some of the most pressing problems of the Anthropocene.