WITHIN THE next few months, the first tenders will be issued for construction of the 2400 km North-South Railway in Saudi Arabia. This is expected to take around five years to complete, and revenue services are expected to begin by 2011.

The NSR is a key component of the Kingdom’s plans to expand its rail infrastructure. The line is primarily intended to transport bauxite and phosphate ores from the north and northeast of the country to processing facilities on the Gulf coast. The railway will also provide passenger and general freight services to the towns in the region, which must now rely on a sparse road network. It will run right up to the border with Jordan, facilitating international trade and promoting economic development and growth.

Unlike the east-west Saudi Landbridge project between Jeddah and Riyadh (RG 3.05 p134), which is being offered to the private sector as a BOT concession, the NSR is being implemented by the government. A comprehensive feasibility study, including a detailed financial analysis, confirmed that the most cost-effective approach would be for implementation of the NSR to be overseen by the Public Investment Fund, which is part of the Ministry of Finance.

PIF will fund the initial capital cost, including both infrastructure construction and the procurement of rolling stock, although it is considered likely that a concessionaire will be selected to operate and maintain the line. Procurement of the civil works, superstructure and rolling stock will follow international standards for competitive bidding.

The Implementation Supervision Consultancy Services contract was awarded last year to a consortium of Louis Berger, Systra, Canarail and the Saudi Consolidated Engineering Co (RG 1.06 p7). The consultants have already started on the 75-month contract, and detailed engineering design is due to be complete early this year.

The NSR will run northwest from Riyadh to Al Hudaitha, with branches serving the phosphate reserves at Al Jalamid in the north and the bauxite deposits at Al Zabirah in the centre of the country. The mineral railway will turn east to run directly from Az Zabirah to Raz Azzawr on the Gulf coast, where the processing plant will be located, and thence to Jubail. The mixed-traffic line will continue south to Riyadh.

Key design parameters for the NSR have been drawn from world best practice in the heavy haul mining railway sector. The route is designed to allow freight trains to run at 80 km/h loaded and 100 km/h empty. The steepest gradient will be 0·5% against loaded trains and 1·5% for empties.

The Riyadh - Al Haditha passenger service is initially expected to operate at 160 km/h, but the alignment is being designed to permit 250 km/h running in the longer term. All structures are being designed for double track, although initially only a single track will be laid, with 11 passing loops 3·5 km long.

Earthworks and structures

The civil works tenders are to be awarded progressively through 2006, with priority being given to the mineral lines followed by the passenger and general freight sections.

The earthworks contracts cover construction of the roadbed up to the bottom of the ballast layer, excluding bridges and culverts. In total, they are expected to require 120 million m3 of embankment fill and 60 million m3 of excavation, which will necessitate the use of a large number of earthmoving machines.

The second quarter of 2006 is expected to see the award of an ’advanced earthworks’ contract covering the 280 km section of line through the Great An Nufud Desert between Ha’il and Al Jawf, which lies on the critical path. This will entail extensive cut and fill to create an alignment through the sand dunes. The contract will be awarded to Saudi contractors who have specific skills relevant to the movement of sand dunes.

The remaining mineral railway contracts, including earthworks, structures and trackwork, are to be tendered from mid-2006 using an international competitive bidding process. The passenger railway contracts will follow at the end of this year.

The structures element will cover a mix of bridges, culverts and drainage channels. All of the bridges are to be assembled from continuous prestressed concrete spans, with a standard length of 20m selected for bridges to carry the line over the numerous wadis. The prismatic spans are designed to carry conventional ballasted track, allowing the use of a standard CWR trackform throughout and simplifying future maintenance. Reinforced concrete culverts will be cast in situ.

System parameters for the NSR trackwork have been selected to promote efficient heavy haul operations, based on world best practice. The contract will cover all works from the bottom of the ballast layer to the top of rail, including the main line, passing loops, station sidings and special trackwork. The line is being designed to accommodate axleloads up to 32·4 tonnes, with 60 kg/m rail carried on locally-procured concrete sleepers laid at 1800 per km.

The telecommunications contract will provide for the installation of an optic fibre communications backbone along the entire route, although the detailed specification for this is to be revised as the design progresses.

Under the signalling and train control contract, which will also go out to international tender, all passenger and mixed-traffic lines are to be equipped with a full CTC signalling system. A computer-assisted manual block system is envisaged for the mineral-only sections. Monitoring and safety equipment to be installed will include hot axlebox and dragging equipment detectors.

For planning purposes, a standard mineral train is expected to be formed of two or three 4400hp AC-motored diesel locos and up to 160 wagons, giving train lengths ranging from 1 000m up to a maximum of 3 390m. General freight would be handled with intermodal equipment, including RoadRailers as well as conventional containers. Five trainsets formed of two locos and 65 to 125 wagons will be needed, with a projected cycle time of two days.

CAPTION: Awarded to an international consortium, the Implementation Supervision Consultancy Services contract covering design and project management for the North-South Railway was formally signed in Riyadh by Minister of Finance Dr Ibrahim Al-Assaf on November 29 2005