SOFTENED WATER BENEFITS STUDIES

Summaries and educational materials (toolkits, handouts, infographics, etc.) are publicly available resources, and the full scientific reports are free for Water Quality Association (WQA) members.

 ​If you are not a WQA member, please contact [email protected] to inquire about access to the full report(s) of interest. 
Combined Executive Summary  l  Two-page Summary of the studies

Energy Saving Study
Conducted by ​Battelle Memorial Institute

Focused on efficiency improvements in household water heaters from the use of softened water, and the subsequent effect on performance of fixtures.
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Executive Summary
​Full Report
​The Energy Savings study examines the impact of removing water hardness on household energy efficiency and appliance performance. The research tested water heaters, faucets, showerheads, dishwashers, and laundry machines under controlled conditions to compare the effects of softened versus hard water. It examined scale buildup, operational efficiency, and maintenance needs, as well as environmental factors like carbon footprint. This study offers valuable insights for homeowners, plumbing professionals, and sustainability advocates on how water softening can enhance appliance longevity, reduce energy consumption, and promote cost-effective, eco-friendly home water management. WQRF is repeating this study starting in 2026 to account for advances in technology.

Dishwasher Study
Conducted by ​Scientific Services S/D, Inc. 

Quantified the relative effects of hardness and detergent dosage to show savings possible by softening hard water.
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Executive Summary
Full Report
​The Dishwasher study examines the impact of water hardness and detergent dosage on the performance of automatic dishwashers. The research tested multiple detergents and varying hardness levels to evaluate soil removal, spotting, and filming on dishes. The study demonstrates that softened water significantly improves cleaning results, reduces spotting and filming, and allows for substantial detergent savings compared to hard water. These findings provide valuable insights for homeowners, appliance manufacturers, and sustainability advocates seeking efficient dishwashing solutions and to reduce environmental impact. WQRF is repeating this study starting in 2026 to account for advances in technology and soap formulation.

Laundry Study
Conducted by Scientific Services S/D, Inc. 

Compared the effects of detergent dose, water hardness and wash temperature on the stain removal performance of five household laundry detergents. 
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​​Executive Summary
​​Full Report
​The Laundry study investigates the impact of water hardness, detergent dosage, and wash temperature on stain removal in household laundry. The research tested multiple detergents and nine common stains under controlled conditions. Results show that softening water dramatically improves cleaning performance, even when detergent use and water temperature are reduced. This study highlights opportunities for energy savings, lower detergent costs, and improved fabric care, providing valuable insights for homeowners, appliance manufacturers, and sustainability advocates seeking efficient and eco-friendly laundry practices. WQRF is repeating this study starting in 2026 to account for advances in technology and soap formulation.

CALCULATE POTENTIAL SAVINGS

RELATED PROJECTS

Study compared the chloride discharge to controls for neighborhoods that optimized existing water softeners and neighborhoods that replaced equipment with high-efficiency rated systems.
This study was undertaken to investigate the effect home ion-exchange water softeners may have on the performance of
​onsite septic tanks.

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