Melen Water Supply System
Conveyance + treatment, Approximately 1 billion m3/year planned transfer; Bosphorus tunnel stage estimated at 2.8 million m3/day in Turkey.
Awarded
The record
- Country
- Turkey
- Location
- Istanbul
- Coordinates
- 41.050, 29.000
- Technology
- Conveyance + treatment
- Capacity
- Approximately 1 billion m3/year planned transfer; Bosphorus tunnel stage estimated at 2.8 million m3/day
- Capital cost
- US$367 m: Melen Dam completion contract, TRY 14.496 bn (Limak, June 2026), at TRY 39.45 per US$ (World Bank official exchange rate, 2025 average); no cost published for the whole system
- Stage
- Awarded
- Owner or client
- DSİ (State Hydraulic Works) / İSKİ
- Contractor
- —
- Operator
- —
- Finance
- Government
- Award or start year
- 2027
- Commissioned
- —
Record last checked 2026-09-20.
History
- 2001
First stage of the Great Melen Project starts, diverting Melen Stream water by tunnel and pipeline to the Ömerli Dam
- 2014
Urgent expropriation decisions evacuate Ortaköy and twelve other villages in the planned reservoir area
- 2016
Original target year for completion of the Melen Dam missed
- 2019
Halt of dam construction after cracks in the dam body becomes public
- 2026-06
DSİ awards the completion works to Limak on 11 June 2026, the fourth tender on the dam since 2012
Sources
4 references
Every field in the record above is taken from the references below. A field that none of them confirms prints as a dash.
- Water Alternatives, Kırcı and Aydın, Feeding Istanbul: The Melen water transfer project and the anatomy of a silent environmental conflict, vol. 19 issue 2, 2026 (PDF). water-alternatives.org.
- A Yeni Ankara report of 29 June 2026 on the repeated completion tenders was cited here and has since been taken offline, so it has been removed; nothing in this record rests on it.. The sheet's US$900 million cost is not supported by any fetched source and has been removed.
- Yatırımlar, DSİ Melen Barajı tamamlama işi için sözleşme imzaladı, June 2026. yatirimlar.com.
- MENA Water Review major projects register and PPP pipeline — compiled from procurer publications, development-bank project pages and trade reporting; each record names its source.
The İstanbul Melen Dam completion tender was held on 11 June 2026 and the contract signed with Limak İnşaat on 22 June 2026 for TRY 14,496,000,000. The Limak award is counted once, in the awards log (fact-check TR0423, October 2026).