The Sections within the Department of Civil Engineering are organized through the Operating Units for Track Maintenance (OU-TM), which cover portions of 20-30km.

TM Section Doboj consists of ten OU-TMs, the following eight being active:

- OU-TM Modrica
- OU-TM Dragalovci
- OU-TM Doboj I
- OU-TM Doboj II
- OU-TM Kostajnica
- OU-TM Sockovac
- OU-TM Zvornik Novi
- OU-TM Workshop

and 2 currently inactive:

- OU for mechanical track maintenance Zvornik
- OU ballast pit Doboj

TM Section Banja Luka consists of the following 7 OU-TMs:

- OU-TM Ukrina
- OU-TM Banja Luka
- OU-TM Omarska
- OU-TM Prijedor
- OU-TM Novi Grad
- OU-TM Dobrljin
- OU-TM Workshop

Operating units of the TM Workshop perform the maintenance of large and small mechanical units, railway facilities along the tracks and other facilities which the ZRS has at its disposal. Other OU-TMs maintain tracks with facilities where the railway transportation is operating.

INFORMATION ON THE LINES IN TERRITORY OF THE REPUBLIC OF SRPSKA

The total of constructed length of lines in the area of the ZRS is 418,290km of which:

- 393,690km goes to single-track lines,
- and 24,600km goes to double-track lines

which makes the total of 442,890km of the open track with the main running lines.

There is total of 338,069km of electrified lines (25kV, 50Hz) of which:
- 313,469km goes to single-track lines,
- and 24,600 km goes to double-track lines.

The total length of other station tracks is 162,150. The total length of the tracks (open tracks with the main running lines and other station tracks) is 578,144km where the railway transportation is operating.

In the territory of Republic of Srpska, the Railways of the Republic of Srpska organize the transportation on the portion (total constructed length of 363,912km) on the following routes:

- Entity border - Samac – Doboj – Entity border: 80,972km
· single-track 56,372
· double-track 24,600

- S. Kostajnica – Banja Luka – Novi Grad: 174,412km
- State border(Croatia) – Dobrljin – Novi Grad: 18,544km
- Novi Grad – Blatna – Entity border: 19,600km
- Entity border – Petrovo Novo – Doboj: 29,194km
- State border(Croatia) – Brcko – Entity border: 7,840km
- Entity border – Caparde – Zvornik Novi – State border(Serbia) : 21,332km
- Omarska – Tomasica: 10,700km

There is a part of the ZRS lines where the Serbian Railways are operating:
- portion Jablanica – Strpci and,
- portion Sremska Raca – Bijeljina

in total constructed length of 27,399km.

One portion of the lines is currently non-exploited in total constructed length of 26,979km:
- portion Brezicani – Ljubija
- Modrica – Gradacac
- Brod – Stata border (Croatia) – Slavonski Brod
- Spreca – Doboj suburb

The lines are mainly od category D-4 with admissible load of 22,5 tons/axle and 8 tons/meter, gauge: 1435mm.

The lines are constructed with S-49 rails, mostly with wooden sleepers (partially with concrete sleepers) , „K“ and „SKL“ track fastening equipment and with dolomite ballast chips. The tracks on the open lines are welded and included in the continuous welded rail (CWR).

MECHANICAL UNITS THAT RAILWAYS OF THE REPUBLIC OF SRPSKA DISPOSE OF
WITHIN THE DEPARTMENT OF CIVIL ENGINEERING