Dammam–Riyadh line

There is an upgrade ongoing to replace level crossings with grade separations,[1] and to bypass of the centre city of Hofuf.[2] This shall allow 200 km/h speed.

In 2014, the SRO awarded a contract worth US $1.6 million to a consortium led by Spanish firm Consultrans to study alignments for a high-speed line linking Riyadh and Dammam.[3]

In December 2015, the SRO President stated that the speed of trains on the line would be raised from 140 km/h to 160 km/h before the end of the year, and would further be increased to 180 km/h in 2016.[4] On 7 December 2015, SRO began operating passenger services on the line using new CAF push-pull trainsets which operate at 180 km/h. The trains entered service just as the SRO had completed double-tracking of the entire 449 km line.[5]

On 17 February 2017 at about 1:00 am, a train on the line derailed near Dammam, injuring 18 people, after flooding from torrential rains caused the rail line to erode. The train was carrying 193 passengers and six crew members. SRO stated that all injuries were minor. All passengers were transferred to another train and transported to Dammam station.[6] The line was closed for repair following the accident, and SRO suspended all rail services to Dammam. Services were only operated between Riyadh and Hofuf.[7] Full services were resume by 23 February 2017.

The SRO's fleet consists of 102 diesel locomotives and 75 passenger cars. These are classified into 12 cars of Al-Rehab class with a capacity of 540 seats, 9 cars of Al-Taleaa class with a capacity of 652 seats, 25 cars of Al-Qafila class with a capacity of 2,012 seats along with 2 special-class cars, 8 diner cars, 12 luggage and power generation cars and 1 car that has been specially fitted as an ambulance car to enhance safety.[10]

Spanish manufacturer CAF has in delivered 2012 delivered eight fast diesel locomotives, with one driving van trailer passenger car and four other passenger cars, with a leading power car unit; plus two spare power cars. They are used on the Dammam–Riyadh Line. During 2013 the travel time is 4:15 but there is a target of 3:00 for the future.

Class	Image	Top speed		Number	Remarks	Built
		mph	km/h
EMD SW1200				5	Diesel-electric locomotives. Series 1022-1026[11]	1950-60
Class 2400		50	80	7	Secondhand Diesel-electric locomotives taken over from NS by Volker Stevin in 1976 for construction works for a seaport in Jubail. Former 2427, 2445, 2485, 2497, 2499, 2519, 2523. Renumbered into 101-107. Sold to Archirodon for rail reconstruction between Damman and Riyadh and renumbered to 276-04 - 276-09. Some scrapped in 1983. Others active until 1994 and stored in Hofuf afterwards.[12]	1954-56
EMD GP18					Diesel-electric locomotives. 1200[11]
EMD FP7A				2	Diesel-electric locomotives taken over from Arabian American Oil Company (there 1006-1007).[13]
EMD SD38-2				6	Series 2004-2009. Order 778050. Diesel-electric locomotives[14]	1978
EMD SD50					Diesel-electric locomotives[15]
EMD SD70ACS				25	Diesel-electric locomotives for a mineral railway[16]	2010
CAF		112	180	8 Passenger Units & 10 Power Cars (5001-5010)	Passenger Trainsets with dedicated Power Cars.	2011
Class 319.2		75	120	>4	(Series 319.)Diesel-electric locomotives bought second hand.[17]

The rails on the line are of the type C.W.R UIC 60.[18]

In 2007, the SRO contracted a consortium made up of Siemens Transportation Systems and the Saudi Arabian Nour Communications Company to modernize both the Dammam–Riyadh line and the cargo line of SRO rail network. The line will be equipped with signalling technology including an electronic interlocking as core of the installation and Trainguard 100 for ETCS Level 1. GSM-Railway (GSM-R) mobile radio technology will be used for communications on the entire rail network.[19]