Plans for the Doha Metro Network have been presented to the Qatar Government and are currently under consideration.
The contract could be awarded by the end of this year, a consultant working on the project said. The plans form one "cluster" of a wider consolidated national railway network.
The wider network is designed to integrate five railway systems planned across Qatar into a "comprehensive and consolidated national railway system."
It was prepared by DB International, the international wing of German railway company Deutsche Bahn, and state-owned firm Qatari Diar Real Estate Investment Company.
Last August it was announced that the two firms had signed an MoU to develop the conceptual design. The Urban Planning and Development Authority is overseeing the work.
"The plans include Doha Metro as one cluster," DB International spokesperson Bernd Weiler told Construction Week.
"There are further clusters involving other forms of rail traffic including a line to Bahrain and a line south to Saudi Arabia."
Weiler confirmed that a presentation had been made last month to the Qatar Government. When asked how the government had received the plan, he said: "I have read reports which are friendly but neutral."
According to Doha's application to host the 2016 Olympic Games, phase one of the metro involves five sections, originally scheduled for a 2015 completion date.
But Qatar was eliminated from the running for the Olympics last June, making the 2015 completion unnecessary and unlikely.
PTV Doha manager Steve Cole, who is also involved in the wider masterplan, told CW the construction timetable, including the contract type, would not be agreed on until "the second half of this year."
"The kind of metro they are looking at is mostly underground, which takes time," Cole added.
The first section, running 30km from the under-construction Lusail mega-project to Doha International Airport, was valued at US $1.65 billion (QAR6 billion) in the Olympic application.
The four further sections, originally set to break ground between 2010 and 2012, run a total of 55km and were valued collectively at $3 billion.
Together, the five sections constitute the first phase of a long-term three-phase plan, with a preliminary 2026 completion date. All three phases total 140km.
The Olympic application confirmed that the city's planned transport infrastructure "will be developed, regardless of the International Olympic Committee's choice of host city for 2016." Qatari Diar was unavailable for comment.
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