The Hidden and "Hard" Cost of Water in Dialysis Center Planning

Background: Hemodialysis requires up to 500 liters of water per session, raising economic and environmental concerns. Although clinical guidelines focus on chemical/microbiological quality, water hardness—reflecting calcium and magnesium content—remains overlooked in dialysis planning. Hard water reduces membrane lifespan, increases resource use and costs. This study analyzes field data to quantify the cost impact of hard water prior to treatment and its effect on system durability and service sustainability. Methods: Cross-sectional observational study conducted in five cities across Ecuador’s Andean region. Key variables included raw water hardness (expressed in parts per million) salt consumption for softener regeneration, reverse osmosis membrane lifespan, annual maintenance costs for pretreatment infrastructure, and the cost per cubic meter of treated water with data from 2020-2024. Cities were categorized by hardness level (soft, slightly hard, hard, and very hard), and descriptive and comparative analyses were performed to evaluate differences in operational costs according to baseline water hardness. Results: Water hardness ranged from 43 to 286 ppm. In cities with levels >125 ppm, salt use rose by 35–50%, membrane replacement doubled, and annual treatment costs increased by up to 75%. The cost per cubic-meter of treated water nearly doubled with higher hardness. Membrane lifespan dropped by up to 60%, in cities with hard water documented. Conclusion: Water hardness is overlooked yet impactful factor in dialysis center planning. Higher hardness increases costs and deterioration. Assessing hardness early can improve investment decisions and support sustainable and precise dialysis planning. Routine hardnes evaluation in nephrology planning, is reinforced by this study.