System Status
Nero
Greece — dam levels — latest data & analysis
of total capacity
Stored
772.5 MCM
Total Capacity
1551.0 MCM
Last Updated
2026-04-25
⚠ Data for this country may be incomplete. We are actively working with the appropriate authorities to improve coverage.
System Capacity
All 4 Dams
Understanding Athens' Water Supply
Greece's water security is concentrated in a vast network of reservoirs spanning from the Peloponnese to the Pindus Mountains. This dashboard provides access to EYDAP (the Hellenic Water and Sewerage Company) data from Greece's major reservoirs, updated every six hours. As of March 2026, the eastern Mediterranean's historic drought has pushed Greece's water reserves to critical levels, making transparent access to this data essential for citizens, farmers, and policymakers.
How to Read This Dashboard
The system capacity chart shows the combined fill level of Greece's major reservoirs over time. You can switch between historical trend and year-on-year comparison views to track seasonal patterns. The dam grid displays each reservoir individually, colour-coded by severity: red (critical) means the reservoir holds less than 20% of capacity, amber (warning) indicates 20–40%, and green (healthy) means above 40%. Click any dam card to explore its full history, technical specifications, and year-on-year comparisons.
What the Numbers Mean
Percentage represents the reservoir's current storage relative to its maximum design capacity. Below 20%, the system enters critical territory where evaporation accelerates, water quality degrades as sediment concentrates, and extraction becomes physically limited. MCM (Million Cubic Metres) is the standard unit for reservoir volumes. Greece's major reservoirs have a combined capacity of approximately 1,500 MCM. Athens alone consumes roughly 600 MCM annually for domestic use, while agricultural irrigation across Attica adds 300+ MCM to demand.
Why Monitoring Matters
Reservoir levels directly determine Greece's water policy, irrigation allocations, and the energy cost of desalination. When levels drop below critical thresholds, the government restricts agricultural water, mandates higher desalination, and may impose rotating supply restrictions. The 2024–2026 drought — the worst in a generation — has shown how quickly a water system can transition from surplus to crisis. Real-time access to this data empowers citizens, journalists, and researchers to track the country's water emergency independently, without waiting for official announcements.
Data sourced from EYDAP (Hellenic Water and Sewerage Company) public records.