Achieving Net Zero Water in Severe Drought Prone Areas: A Case Study of Catchment, Storage, and Infiltration Optimization

Abstract

Net zero water or water independent buildings capture rainwater to meet potable water demand. These systems require a careful calibration between catchment size, storage capacity, and infiltration area to achieve performance goals. In severe drought prone areas with wider variability of rainfall and long periods of scarcity, the precision of the calibration between these three variable is more narrowly defined to reach system resiliency. This paper analyzes a case study of a midsize office project in the severe drought prone area of Los Angeles, California that aims to achieve net zero water. The interrelation of the three variables are analyzed against daily precipitation over the last 10 years to identify dependencies and critical break points. The study finds that in severe drought prone conditions, storage size is relevant only up to a threshold closely mapped with demand. Net zero water system resiliency is accomplished through the precise interrelation of catchment area and infiltration capacity.