Abu Mansour Dam
Dam (storage and irrigation), Reservoir about 22.3 million m3; dam height about 75 m; earthen dam with a compacted clay core and rockfill faces in Libya.
Out of service
The record
- Country
- Libya
- Location
- Derna
- Coordinates
- 32.628, 22.433
- Technology
- Dam (storage and irrigation)
- Capacity
- Reservoir about 22.3 million m3; dam height about 75 m; earthen dam with a compacted clay core and rockfill faces
- Capital cost
- —
- Stage
- Out of service
- Owner or client
- Libyan government
- Contractor
- Yugoslav design and contracting firm
- Operator
- —
- Finance
- —
- Award or start year
- 1973
- Commissioned
- 1977
Record last checked 2026-09-18.
History
- 1973
Construction started under a Yugoslav contractor
- 1977
Dam completed
- 1998
Cracks observed at the base and an Italian study commissioned, whose recommended repairs were never carried out
- 2023-09
Dam overtopped and failed on 11 September 2023 during Storm Daniel, with about 12,000 deaths in Derna
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.
- Association of State Dam Safety Officials, Case study, Abu Mansour and Al-Bilad Dams (Libya, 2023). damfailures.org.
- Built 1973 to 1977 by a Yugoslav design and contracting firm for water supply, irrigation and flood control; Abu Mansour 140 feet high with 18,200 acre-feet of storage, about 22.4 million m3, at about 550 feet above sea level; drainage area 215 square miles; both dams failed on 11 September 2023, releasing about 24,300 acre-feet and deepening flooding across most of Derna by 6 to 20 feet compared with a no-dam scenario; roughly 12,000 deaths and about 2.1 billion dollars of property damage; cracks were observed at the base in 1998 and an Italian study recommended rehabilitation and a third dam, none of which was carried out; case study coordinates 32.757365 and 22.637121 for Derna.
- FAO AQUASTAT, Geo-referenced database on dams, Africa file. firebasestorage.googleapis.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.
Lists Abu Mansur in Darnah on the Abu Mansur river, 1978, 75 m high, 22.3 million m3, 1.2 km2, irrigation and flood control, at 32.6278 and 22.4333. The two sources differ on the completion year, 1977 against 1978.