The Carbon Cost of Leakage: Attributing Electricity-Related Greenhouse Gas Emissions to Real Water Losses in Greek Utilities

<jats:p>Water lost from drinking-water distribution systems has already consumed electricity, yet the associated operational greenhouse gas burden is rarely quantified because water balances and organizational emission inventories use different system boundaries. This study links the two within the Greek managerial-adequacy framework using a purposive availability sample of eight utilities and 14 utility-year observations for reference years 2024–2025. We calculate water-supply energy intensity, operational electricity-related carbon intensity per cubic metre of system input (ISO 14064-1 Category 2), and emissions allocated to reported real losses. Because organizational inventories include activities outside water supply—fugitive wastewater emissions reach 94% of the declared total in one island municipality—we classify itemized electricity supply points by activity and grade attribution quality. Energy intensity ranges from 0.538 to 2.434 kWh/m³ and system-input carbon intensity from 0.198 to 0.895 kg CO₂eq/m³. Under proportional average-intensity allocation, reported real losses are assigned 22.0–67.5% of each utility’s water-supply electricity emissions and 2,708 t CO₂eq in the 2025 cross-section. These are accounting allocations from top-down water balances, not direct measurements of leak-specific energy use. A conditional screening analysis shows that, under a one-for-one production response and the illustrative unit-cost assumptions adopted here, leakage-reduction scenarios overlap selected European public-investment carbon-value benchmarks. The results support activity-level electricity reporting and joint consideration of leakage, energy intensity, and system scale when prioritizing mitigation.</jats:p>