Assessing the Potential of Urban Water Efficiency: with Focus on Outdoor Efficiency and the Commercial, Industrial, and Institutional (CII) Sector

Climate change threats have become one of the most pressing issues of our time and California has felt this acutely. The state faced its driest period on record during the 2011-2017 drought, and in 2021, is faced with the start of yet another major drought. The state is dependent on a highly engineered water management system, with miles of distribution systems and large reservoirs to get water to its residents at the times it is needed. This system is no longer sustainable in the face of a changing climate. A key solution for California that is cost-effective and requires minimal new resources is water efficiency and conservation. In this dissertation, we examined the potential for efficiency to create new water supply and provide multiple other benefits. We first examined and quantified the water savings available from each sector and in each hydrologic region across the state by adopting efficiency improvements such as efficient devices and climate-appropriate vegetation. Next, we reviewed the many benefits attributed to sustainable landscapes, i.e., landscapes that are irrigated efficiently, exist in harmony with their environment, and require minimal external input. In the next two chapters, we studied efficiency within the commercial, industrial, and institutional (CII) sector. We first evaluated through a quantitative analysis the outdoor water use patterns for CII customers at a water supplier in Southern California. Next, we evaluated factors that motivate and hinder decision-making at a CII site to encourage uptake of sustainable landscapes within the sector. We found that efficiency improvements can save between 2.1 to 3.2 million acre-feet of water statewide. Sustainable landscapes are a key solution that contribute to additional supply while also providing benefits such as groundwater recharge, improved water and air quality, and community benefits. For urban areas to harness their full efficiency potential, the CII sector needs to be part of the solution. We found opportunities for savings within this sector but also a need for more study and understanding. Our key final recommendations discussed the need for ambitious efficiency policy for existing buildings, more study into CII end-uses, and targeted and aggressive outdoor efficiency policy