Reconstruction of Two 110 kV Transmission Lines in the Čačak Corridor — a dual-contract programme under a single contractor

Context

Elektromreža Srbije (EMS), the Serbian transmission system operator, launched a reconstruction programme covering two parallel 110 kV overhead lines forming the backbone connections within the Čačak distribution corridor. Both contracts were awarded to the same contractor — Energomontaža a.d. of Belgrade — through separate open public procurement procedures conducted in spring 2016.

Both contracts covered the full scope of transmission line reconstruction — equipment and material procurement, civil and electromechanical works, factory acceptance testing, commissioning, trial operation, and handover — with the contractor assuming full risk and liability throughout a five-year defects liability period.

My Role

I was engaged as project manager coordinating the parallel delivery of both contracts. The core challenge was not managing a single project but establishing a shared governance structure across two formally independent contractual frameworks that shared the same contractor, the same corridor, the same completion deadline, and the same contractual logic — yet required separate approval chains, documentation sets, and interim payment certifications.

The role covered: coordination with EMS technical supervision, monitoring of construction programmes for both lines, oversight of equipment procurement (Al/St 240/40 conductors, insulator strings, OPGW ground wire), management of factory acceptance test schedules, and ensuring completeness of documentation for interim and final payment applications.

Challenges

Simultaneous delivery of two contracts under the same contractor creates a structural tension: shared resources — equipment, plant, and labour — naturally gravitate toward whichever line is running ahead, while both contracts formally demand full commitment and independent timelines. Managing this required explicit capacity planning and clear delineation between the two site teams from the outset.

Health, safety, and environment documentation added significant administrative load: each contract required its own complete set of occupational safety records for every worker on site — individual HSE agreements with EMS, fire protection declarations, medical fitness certificates, and equipment inspection records. In conditions of parallel mobilisation across two active sites, this became a project management task in its own right.

Equipment procurement required careful sequencing: factory acceptance testing of the Al/St 240/40 mm² conductors supplied by domestic manufacturer Elkok a.d. (Kosjerić) and the OPGW ground wire had to be attended by authorised EMS representatives, directly conditioning the start of stringing operations on both lines.

Outcome

Both transmission lines were delivered within their respective 12-month contractual programmes. Conformance with EMS requirements was confirmed through internal technical review, statutory technical inspection for the operating permit, and a successfully concluded 90-day trial operation period on each asset. Handover without objection activated the five-year defects liability period under both contracts.

A combined programme value in excess of €1 million was delivered through coordinated parallel execution within a regulated public procurement environment, with full documentary and financial compliance to EMS requirements and the applicable legislative framework of the Republic of Serbia.