Asset Maintenance

Eleyele's Completion Review Found an Unassigned Maintenance Role

Published 4 November 2026 Publisher IMWO Region Africa Confidence Confirmed
Eleyele Dam functional diagram traces the spillway to the downstream channel and the separate scour and raw-water lines through the shared tunnel

IMWO original Eleyele functional diagram from the November 2016 assessment and IUFMP's 2020 completed-work account; not an as-built drawing or operating procedure.

The World Bank's 28 February 2025 completion report for the Ibadan Urban Flood Management Project recorded Eleyele Dam's maintenance responsibility as still pending. The dam had been commissioned on 29 May 2020 after spillway, embankment, intake and outlet rehabilitation. The project owner's account names CGC-CHWE JV as works contractor and Tractebel Engineering, with SGI Consulting, for design and supervision. This completed civil-work package needed an operating handover covering both flood release and raw-water supply. [1][2]

Commissioned works and a later maintenance finding

IUFMP's April-June 2020 newsletter describes completed components and commissioning. The November 2016 assessment, disclosed in January 2017, explains the intake and scour-tunnel arrangement. The Bank's February 2023 implementation report lists the dam rehabilitation as complete. Its February 2025 review identifies the later maintenance and emergency-preparedness gaps. [1][2][3][4]

The water-supply pipe shares the scour tunnel

The scour tunnel carries the draw-off pipe to the treatment works as well as serving the reservoir's flushing route. The assessment describes a roughly 56 m tunnel with the raw-water pipe along one side; the intake tower serves water abstraction and reservoir drawdown [3]. IUFMP's completed-work account lists replacement of a 600 mm scour pipe and a 450 mm raw-water pipe, new valves and a valve chamber, together with access and monitoring equipment [1]. Those are separate maintained assets sharing a constrained access route. A tunnel intervention has to account for the waterworks connection and the availability of the outlet. The flood route extends through another group of works: the reconstructed ogee weir, widened spillway channel, the junction with the scour channel and the protected river course towards Ologun-Eru Bridge. The maintenance boundary should follow those connected functions through to the receiving channel [1][3].

Evidence conclusion

Hand over the complete operating route

The wider project's asset-management plan was finalized in May 2024 but had not entered formal use by the 28 June closure. The Bank's review assigns drain and channel desilting to the environment ministry while leaving the dam's maintenance responsibility pending. It also records a need to strengthen implementation of the Eleyele emergency-preparedness plan. [2] For the handover, give a named lead operator the dam and outlet asset register, approved operating procedures, inspection responsibilities and a funded maintenance programme. Link the 600 mm outlet, the 450 mm supply line, their valves and access arrangements to the waterworks operator's isolation and service-continuity procedures. Work that affects reservoir levels must follow the approved dam-safety operating envelope. A blocked tunnel access route can defer work on both lines; a spillway-channel maintenance order needs its downstream receiving reach included. The handover register should record these linked interventions and identify who can authorize, fund and restore each affected function.

Outstanding evidence

  • Post-February 2025 assignment of the dam maintainer, asset-management budget and formal operating arrangements
  • Final as-built hydraulic routing, current dam-safety assessment and approved reservoir operating envelope
  • Current outlet, supply-line and monitoring condition; maintenance and emergency-plan exercise records

Related records 1

Subject index

Related subjects

These subject pages bring together related projects, technical articles, reports, and evidence methods.

Sources used 4

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