Technical assistance services for the upgrading of railway infrastructure in Mezdra – Gorna Oryahovitsa section (Sofia), including 26 bridges - Section length 122 km

The project is divided into three stages:

  • Feasibility study
  • Detailed preliminary design
  • Preparation of tendering documents

The design involved the upgrading of 122 km of electrified double-track line, including the following: civil works, track, electrification and signaling and telecommunication systems.

The line is intended for mixed traffic (freight and passengers) with a maximum design speed of 160 km/h.

Railway equipment: double-track on ballast with mono-block concrete sleepers and standard gauge (UIC-60 rail), long welded rail with flexible fastening (SKL-1).

Civil works, track and catenary for two sections of the railway line:

  • 117 km of electrified double-track line (sections 1 and 2) and 5 km of electrified single-track line (section 3)
  • Design speeds: 130 km/h (section 1), 160 km/h (section 2) and 40 km/h (section 3)
  • Current commercial speed: 80 km/h (section 1), 120 km/h (section 2) and 40 km/h (section 3)
  • 26 bridges
  • 11 level crossings to be removed.
  • Partial upgrading of the catenary.
  • Complete upgrading of the track.
  • Improvements to the stations.
  • Upgrading of the track surface at Gorna Oryahovitsa and Tcherven Bryag stations.
  • Construction of branch lines at Tcherven Bryag and Humata stations.

Signaling and telecommunications systems:

  • Interlocking at Gorna Oryahovitsa and Tcherven Bryag stations.
  • Fiber optic cable across the whole line (206 km)
  • Adjustments to the Equipment Offices of 22 stations.
  • Adjustments to the PABX (5 units)
  • Facilities must comply with ETCS Level 1.
  • Installation of equipment compatible with GSM-R (with the relevant interfaces)
  • Preparation of the technical specifications in accordance with FIDIC and Bulgarian regulations.
  • Design of the lighting system for the stations (it is not specified if it must be designed for the two above-mentioned stations or for all the stations across the line).


European Union

Project Dates

2007 – 2010



Project Figures

Contract Value: 5,460,000 €