Integrated Water Conservation Measures for Single-Family Homes: A Multi-City Assessment

Water plays a critical role in residential consumption, accounting for a significant share of public water supply use. With increasing concerns over water scarcity and projections that a large portion of the global population will experience water stress by 2050, the need for effective water conservation strategies has become more urgent. This study evaluates the application and combined impact of water conservation measures in single-family homes. A deterministic modeling framework is developed to estimate household water consumption and conservation potential across four U.S. cities, namely, Houston, Phoenix, Las Vegas, and Des Moines, representing diverse climatic conditions. The analysis incorporates rainwater harvesting, HVAC condensate recovery, water-efficient fixtures, and greywater reuse systems. Scenario-based forecasting, including adoption rates of 1% and 5% of existing homes alongside new construction, is conducted over a six-year period using exponential smoothing techniques. Results indicate that the combined implementation of these measures can generate substantial aggregate water savings, with outcomes varying by climate and location. Greywater reuse and water-efficient fixtures consistently provide the largest contributions, while rainwater harvesting and condensate recovery depend more heavily on regional conditions. These findings highlight the importance of integrated and location-specific strategies and demonstrate the potential of decentralized, residential-level interventions to reduce demand on municipal water systems.