Preliminary Design of Irrigation System on Agricultural Areas in Semberija, Bijeljina municipality (10.000 ha) with Pilot Project BNZ-5 Irrigation System in Donje Crnjelovo for the Area of 500 ha


Preliminary design was prepared for development of irrigation systems for the 10.000 ha of agricultural land in Semberija. Water supply source is the existing channel network. This network abstracts water from the river and transports it to the Sava river. Beside drainage of waters which was performed up to now, this project affirms also its irrigation purpose, that is, promotes multipurpose use of channel network in Semberija.

Preliminary technical concept of development of Semberija irrigation system out of channel network was developed, and Detailed design foreseen implementation of Pilot area on the surface of 510,8 ha which was identified within the Preliminary design, throughout multipurpose analyses, as most favourable out of 24 identified subsystems.

Preconditions for development of irrigation system in Semberija

Agricultural areas in Semberija have priority due to its development possibilities since this agricultural land is of the high quality class, it is very suitable for implementation of big and economical amelioration systems.

Extensive use of  land along the Sava and Drina rivers was provided by: jointing and landscaping of properties with developed road network, applied agricultural and chemical amelioration measures, especially in the area of acid soil and swamp areas along Sava.

By implemented systems (channel network with pump stations), GOK boundary channel (main boundary channel) and MOK (Majevica boundary channel) for drainage and Selište boundary channel, Semberija mostly solved problem of drainage of internal waters and protection against flood inland waters. Protection against external waters is solved by dykes on big watercourses, namely, Sava and Drina and on river engineering works within the area. Construction of 33 km long Left Drina dyke will provide protection for entire area of Semberija against Drina flood waters.

Analyses of the project scope – Spatial area and Subsystems of irrigation system of channel network in Semberija

Irrigation system for the Semberija covers 4 spatial units (Bijeljina East, Bijeljina West, Kojčinovac and Obarska) and 24 subsystems at the gross surface of 10.492 ha. Subsystems are connected to the special water supply sources from the channel system, except KOJ-4 and KOJ-6 subsystems provided by the water from the Drina.

Bijeljina East Spatial unit, P= 3.129 ha

Spatial unit Bijeljina east has limited water supply quantities for irrigation of agricultural areas, it mostly relies just on water provided by Stara Dašnica channel, except in narrower part of this system, where water abstraction from Dašnica channel is possible. In order to provide adequate conditions for irrigation to be met as well as the water abstraction for all subsystems in the Bijeljina east, it is necessary to construct Dašnica-Selište junction channel, for irrigation of BNI-2 and BNI-4 systems, as well as barriers for elevation of water in Stara Dašnica channel for water inflow to the Channel IV east. From this channel water is abstracted for irrigation of BNI-6 subsystem.

Bijeljina West Spatial unit, P= 4.151 ha

For providing adequate water quantities for irrigation of Bijeljina West spatial unit, it is necessary to bring sufficient water quantities into Channel IV West for PS BNZ-6, PS BNZ-7 and PS BNZ-8.

This operation is performed via water abstraction object at the Main boundary channel, where water is directed via Channel IV-31 to the Channel IV West and above stated pump stations.

Kojčinovac spatial unit, P=2.905 ha

In Kojčinovac spatial unit, there are two basic sources for water abstraction for irrigation purposes. For irrigation of the subsystem KOJ-4-6 directly from Drina river via PS KOJ-4-6 and indirectly from the Drina river, via Drina-Glogovac junction channel.

Obarska spatial unit  P= 307 ha

Abstraction of water for subsystem at this area is performed from Dašnica channel via PS OBR-1. Layout of spatial units with appropriate subsystems as well as the channel network, is presented at the figure below.

Analyses of possible technical solutions

After the basis and data about the Drina and channel network have been studied in details, reconsidered basis and data on irrigation surfaces and required water quantities have confirmed optimum possibilities for irrigation of agricultural surfaces in the area of the Project relay on channel network as most important water supply source for irrigation purposes.

Preliminary design developed optional solutions considering and analysing most reliable and most efficient irrigation system operation modes. Basic concept of water intake from the channel system and distribution of water via pump stations and main transport and distribution pipelines is considered as well. Tertial network was not considered.

Regarding significant irrigation area, while selecting route for transport and distribution pipelines, the priority was given to use of existing corridors and shortest possible route for achieving reliable connection between water intake with pump station and beneficiary. Routes of transport and distribution pipeline are planned to be led by the shortest way, along the local roads and rarely by estate borders in order to avoid property issues, or at least reduce them to the minimum.

Presented optional solutions for the main transport and distribution pipelines, as linear elements of the irrigation system, essentially do not have significant differences. Only difference is in optimisation of pump station positions and main pipelines dimeters, and it is regarding location of pump station, for providing optimum conditions for water abstraction and transport.

Regarding presented net irrigation surfaces of 8.919 ha, suggested irrigation subsystems and total water needs of Q=4,04 m3/s, three possible conceptual solutions are considered, as follows:

  • Option A1 – optional technical solution for development of irrigation system under high pressure and optimized PS positions, as well as optimized diameters of transport and distribution pipelines. This OPTION is ADOPTED for development of irrigation system in the City of Bijeljina.
  • Option A2 – as sub-option of option A1 that served as basic solution, along with the operation of system under high pressure and as initial option of system under high pressure, later on developed as Option A1.
  • Option B – optional technical solution of irrigation system development under low pressure, the layout of this option and of Option A1 coincide.

Essence of implemented analyses of optional solutions is to determine optimum operation, functionality and system reliability but also to achieve economic optimization of system.

Initial point were two basic concepts for system development with direct pumping under high and low pressure into transport and distribution network of irrigation subsystems. The aim was to reconsider option that will require reliable and safe system operation and which will be competitive regarding required investments. On the other hand, operation costs of water transfer and electricity consumption during irrigation will result with indicators that will be economically assessed on the level of the project period and will be compared between offered options. In order to reach acceptable technical solution that will be appropriate for implementation in the next period, various limitations on possible construction sites and required conditions for construction of objects were considered while reconsidering optional solutions. Limitations on the field were reconsidered after achieving insight into documentation and maps but also after site visits of potential routes of transport and distribution pipelines and water intake locations were performed. Basic limitation factors regarding irrigation system and optional solution analyses are as follows: removing „bottle necks“, regulation of channels, stabilization of the channel slopes, reconstruction of culverts, construction of Selište junction channel.

Adopted technical solution

Adopted optional technical solution for development of irrigation system under high pressure, Option A1, consists out of 24 irrigation subsystems and 23 water intakes with pump stations. Water is transferred from the channel system directly into system of main transport and distribution pipelines and to the end users in a way that available pressures at the end of the network- at the outlets- are not below 3,5 bars.

Pump stations. Key objects of this optional solution are pump stations which have to have installed flow at disposal and maximum consumption per hour within relevant day. Calculation of required PS capacity for each subsystem was performed based on calculated required water quantities for each Subsystem, based on adopted pump head at the PS exit and average pump efficiency of 80%. Following table presents overview of designed pump stations with basic characteristics.

Pilot project for irrigation BNZ-5 in Donje Crnjelovo

Reconsidered irrigation subsystems, with location of BNZ5 subsystem in Donje Crnjelovo, (marked in red) are presented at the figure below. This subsystem is selected as Pilot project via multicriteria analyses since extensive agricultural practice is developed in this area, including plasticulture.

BNZ-5 Pilot area is subsystem of „Bijeljina west“ spatial unit with agricultural areas with extensive agricultural production, with huge percentage of vegetable crops in this area. Total potential surfaces that could be irrigated in this „Bijeljina west“ spatial unit, cover area of 4.152 ha.

Detailed design foreseen implementation of BNZ-5 pilot area at the total gross area of 472,47 ha, which was identified out of 24 subsystems as most favourable throughout multicriteria analyses.

The area is divided into two sectors, namely, „south“ with net surface of od 211,92 ha and sector „north“ with net surface of 260,55 ha. Sectors are separated as individual spatial subunits.

Selection of the pilot area was supported by the local community and Agricultural Projects Coordination unit – Ministry of Agriculture, Forestry and Water Management of Republika Srpska.

Figure 1 - BNZ-5 subsystem with presentation of transport and distribution network and PS locations

Water abstraction object was designed for the needs of water abstraction from Stara Dašnica channel.

Water for the pump station with the lateral water intake is abstracted from the Stara Dašnica channel and transported to the water intake pond of  PSBNZ-5 by junction pipeline. For distribution and transport of water to the macro plots (where re-parcellation and road infrastructure rehabilitation was performed) the 30 km long network of transit and distribution pipelines was designed. It was planned to install water meters and introduce monitoring of water consumption.

Figure 2. – Layout of BNZ-5 PS with water intake from Dašnica channel

Layout of BNZ-5 subsystem with pipelines and position of PS with water intake is presented in the Figure no. 1


At the BNZ-5 subsystem it was foreseen to construct 25.448,96 m of transport and distribution pipelines of DN 110/101,6 mm to DN 630/581,8 mm.

Transit pipeline T-1, is central transport pipeline which supply water from the PS BNZ-5 pump station to the main node’s location in RO T-1-1 node, where connects with transit pipelines T-2 and T-3.

T-1 transit pipeline is of following characteristics:

  • Total length, L=718,26 m, DN 630/581,8 mm, HDPE 100, SDR 26, PN 6 bar.

T-2 transit pipeline, is transport pipeline which supply water for “Sector – SOUTH”. Pipeline starts from the junction with the T-1 main transit pipeline in the Main node, node RO T-1-1, chainage 0+000 to Node RO T-2-13, chainage 1+465,91, where connects with distribution pipelines D-2.12 and D-2.13.


T-2 transit pipeline, in total length of L= 1.465,91 m, is of following characteristics:

  • In length of L=608,33 m, DN 450/415,6 mm, HDPE 100, SDR 26, PN 6 bar.
  • In length of L=473,51 m, DN 315/290,8 mm, HDPE 100, SDR 26, PN 6 bar.
  • In length of L=180,66 m, DN 280/258,6 mm, HDPE 100, SDR 26, PN 6 bar.
  • In length of L=203,41 m, DN 225/207,8 mm, HDPE 100, SDR 26, PN 6 bar.

T-3 transit pipeline, is transport pipeline supplying water for “Sector-NORTH”. Pipeline starts from the junction with the main T-1 transit pipeline, in the Main node, RO T-1-1 Node, chainage 0+000 to chainage 2+539,41.

T-3 transit pipeline, in total length of  2.539,41 m, is of following characteristics:

  • in length of L=1.382,75 m, DN 450/415,6 mm, HDPE 100, SDR 26, PN 6 bar.
  • in length of L=610,53 m, DN 315/290,8 mm, HDPE 100, SDR 26, PN 6 bar.
  • in length of L=302,82 m, DN 280/258,6 mm, HDPE 100, SDR 26, PN 6 bar.
  • in length of L=243,32 m, DN 160/147,6 mm, HDPE 100, SDR 26, PN 6 bar.
  • At the BNZ-5 subsystem it was foreseen to construct 25.448,96 m of transport and distribution pipelines in total, of DN 110/101,6 mm to DN 630/581,8 mm diameters.

Beside this, it was foreseen to construct 5.000,00 m of DN 110/101,6 mm pipeline for connection of individual consumers to irrigation system.

Ownership Structure of irrigated area within BNZ-5 subsystem is 100% private property.

Pump station

Surface of the pump station is 115 m2, pump sump is of V=250m3, construction object surrounding plateau of 550 m2 is going to be constructed entirely, and hydromechanical equipment is going to be installed gradually, firstly for BNZ-5 as part of this project, and afterwards will be continued within other projects for BNI-7. 5 pump units + 1 spear pump unit is going to be installed into PS BNZ-5 with water intake located at “Dašnica Stara” channel at this project stage.  Installed pump station PS BNZ-5 capacity is Qi=350 L/s, and installed power is P= 270 kW.

It is important to note that PS object is going to be constructed in phases, and for achieving savings in construction it was foreseen to serve as common PS for subsystems BNZ-5 and BNI-5. Subsystem BNI-5 is located on the opposite side of “Dašnica Stara” channel.

At the final phase, during normal operation, this pump station is going to operate with full capacity of 540 l/sec.

Supervising and control system for automatic regime operation is designed with required protections and with observation of basic water quality parameters in pump station, with oil in water detector. Project foreseen construction of power transformer station and power supply to the PS object.

As this pump station is part of one complex and significant irrigation system, it is equipped with functional and high quality equipment, fittings and assembling (Figure 3).

Maximum discharge achieved by BNZ-5 subsystem in the pipeline amounts to 321 L/s for operating pressure of 5,25 bars. Considering data on required maximum water quantities, in accordance with calculations and Investor’s requirements presented in Preliminary design, five main operating pump units were selected, namely, KSB type UPA 250C-250/3h of individual capacity of 70 L/s, pump head Hp=58 m, pump efficiency h=81,5% and installed power of 54 KW, or other of the same or similar characteristics and one unit as “dry” spear unit that will be located inside the object of PS. Total capacity for all five operating and connected pump units is Q=325 L/s, for Hp=61 m. For meeting low discharges in initial phase of system operation, installation of the frequency regulators is foreseen which provide variation of the discharge based on system requirements. Also, while designing pipe network for pumps it was foreseen to provide possibility to transfer operation of up to two pumps for supplying Subsystem BNI-5 if required and Beneficiary is interested, until the II phase of the PS and pump unit installations are constructed for the BNI-5 subsystem.

Figure 3 – Plan view of the pump station – installation drawing

Cyclic operation of the above-mentioned units is going to provide optimizing the operation of all pump units, but also of wear and tear.  The pumps are going to be controlled over frequency regulators and soft starters. Frequency regulators are installed on three pumps, one on pump with possibility of water supply for BNI-5 subsystem and two frequency regulators to the remaining three pumps provided for BNZ-5 subsystem.  Regular operation foreseen all five pumps operation for water supply of BNZ-5 subsystem while transfer of water for BNI-5 subsystem is going to be performed in accordance with abilities and requirements.

Total installed power of pump units inside the PS is Ni=5x54=270 kW, and the total installed discharge is 325 L/s.