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Executive overview
Key findings
Approximately 4,400,000 residents: population served with water supply; 3,695,500 with sewerage (FY2025 report, actual)
399.7 → 723.9 million m3: withdrawable reserves of the main reservoirs, January 1 to July 1, 2026 (actual)
25.46%: non-revenue water in H1 2026 (actual; 23.70% in 2023)
€2.5 billion: investment plan for 2026–2035 (plan); €77.5 million was absorbed in 2025 (actual)
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Buyer relevance
Who the report is for
Water-resource and drought-resilience advisers
See reserve levels, the reserve sources EYDAP activated and the status of the Eurytos diversion in one place.
Public-sector and regulatory analysts
Follow how the State, EYDAP Fixed Assets, the regulator and four laws passed between 2024 and 2026 divide responsibility for Athens' water.
Engineering and operations suppliers
Compare network lengths, treatment capacities and loads, losses and overflow data before scoping work with EYDAP.
Investors following EYDAP
Read the 2025–2029 allowed revenue, the €323 million disputed claim and the €2.5 billion plan against actual absorption of €77.5 million in 2025.
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Decision scope
Questions answered
Who owns Athens' water supply system?
EYDAP Fixed Assets owns the 495 km External Water Supply System, which EYDAP operates under a contract extended to December 31, 2026; the State holds 61.33% of EYDAP's voting rights.
How did reserves recover after the 2025 drought?
Withdrawable reserves rose from 399.7 million m3 on January 1, 2026 to 723.9 million m3 on July 1, 2026, mainly from rainfall; EYDAP's reserve-source actions added about 56 million m3.
How large is the system EYDAP runs?
Four water treatment plants with 1.8 million m3 a day of capacity, approximately 14,300 km of water mains and 8,716 km of sewers, and five wastewater treatment plants led by Psyttalia.
What changes under Law 5325/2026?
EYDAP's jurisdiction extends into Boeotia, Phocis and Evia, with special succession of about 43 providers expected by July 31, 2027.
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Inside the report
Inside the complete report
Executive Overview
1. Water Resource Profile
2. Governance and Institutional Framework
3. Infrastructure and Service Delivery
Strategic Outlook and Opportunities
Source Register
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Public preview
What to watch next
1. Water Resource Profile
Reserve levels entering the 2026–2027 hydrological year; any Eurytos tender notice and the decision on its funding; the status of the state of emergency.
2. Governance and Institutional Framework
The regulator's response to the €323 million review request; the Council of State hearing; renewal of the External Water Supply System contract for 2027; the first valuations under Law 5325/2026.
3. Infrastructure and Service Delivery
Full-year 2026 non-revenue water against the 25.46% recorded in H1 2026; mains replacement in full-year 2026; the signing of the two main Eastern Attica plant contracts; any change in Psyttalia overflows.
Strategic Outlook and Opportunities
Award of the Rafina/Spata plant and signing of Marathon; full-year 2026 absorption; the smart-meter tender notice; the first regional investment plans under Law 5325/2026; reserve levels and any Eurytos decision.
Treatment assets and service performance: capacities and loads, losses, overflows, drinking water quality and customer service.
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Included
What you receive
The complete PDF report: 12 pages, 6 sections, 17 tables and a register of 22 sources.
This edition
November 2026, First edition.
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Evidence & method
Evidence and method
EYDAP's annual financial reports through FY2025 and its H1 2026 semi-annual report, ESG metrics, sustainability reports and drinking water quality data, the regulator's decisions and EYDAP's 2025–2029 tariff proposal, the tariff schedule, and dated press reports on project status checked to November 12, 2026.
Sources
22 sources, listed in the report's source register. Evidence current to 12 November 2026. Principal data periods: FY2025 annual financial report (year ended December 31, 2025); semi-annual financial report for January 1 to June 30, 2026; operating and environmental data for 2021–2025; project and procurement status as of November 12, 2026. All currency is euros..
Evidence boundaries
This report uses authoritative source material available at the stated research cutoff. It distinguishes published facts, calculated values and analytical interpretation. No independent modelling is performed. Forward-looking analysis reflects published plans, documented trends and stated uncertainties. It does not constitute legal, financial, investment or engineering advice.
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Lead analyst
Robert C. Brears
Founder, Our Future Water Intelligence
Robert C. Brears is a water-security specialist and author whose work examines utility governance, infrastructure investment, climate resilience and long-term water-system change for executive and policy audiences.
- Decision-focused utility intelligence
- Published water-policy author
- Evidence-grounded system analysis
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Buyer FAQs
Before you purchase
Who can use the report?
Licensed for internal use within one purchasing organization. The PDF and its contents may be shared with colleagues within that organization. External redistribution, resale and public publication are prohibited without permission.
How is the report delivered?
The PDF is available to download immediately after confirmed payment, through our secure delivery system.
Can my organization buy wider access?
Institutional purchasing: For invoice enquiries, multi-organization licensing or broader access requirements, contact Our Future Water Intelligence.
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Water Systems Overview: EYDAP S.A.
- Format
- Length
- 12 pages
- Edition
- November 2026, First edition
- Price
- USD 499
11
Report details
Publication details
- Publisher
- Our Future Water Intelligence
- Report family
- Water Utility Intelligence Report
- Edition
- November 2026, First edition
- Format
- Length
- 12 pages
- Reference
- OFW_EXT_WATER_SYSTEMS_OVERVIEW_EYDAP_S_A_efb9aa036421
- Evidence current to
- 12 November 2026
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