Reply to Comment on 'Energy and air emission implications of a decentralized wastewater system'

Complementing centralized water-related infrastructure with decentralized facilities is being considered in some communities and a life-cycle perspective is needed for informed decision making. Our 2012 study presents a framework for analyzing the environmental effects of decentralized wastewater systems. While the analysis framework could be applied to cases with a variety of sizes, we evaluated two currently operating systems in California, one decentralized and one centralized plant with a much larger capacity. The disparate scales of the two plants represent an 'off-the-grid' suburban neighborhood-scale system compared with a similarly sized neighborhood connecting to an adjacent large centralized plant. Deciding whether or not to connect expanding developments to nearby centralized plants is a realistic scenario for future growth, making the treatment plants evaluated in our study a realistic choice for comparison.